Mechanics and Motion

37 soru

Soru 1Soru →

A test car travels along a flat, circular track at a constant speed of 20 m/s20\text{ m/s}. Which of the following statements correctly describes the velocity and acceleration of the car?

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Cevap: The velocity is continuously changing because its direction of motion changes, producing an acceleration directed toward the center of the track.

Cevap

The velocity is continuously changing because its direction of motion changes, producing an acceleration directed toward the center of the track.
Velocity is a vector quantity defined by both speed and direction of travel. When an object moves along a circular path at a constant speed, its direction changes at every instant. Because velocity changes whenever direction changes, the object undergoes centripetal acceleration directed radially inward toward the center of the circle.

Adım Adım Çözüm

1
Distinguish between the physical definitions of speed and velocity.
Speed (20 m/s20\text{ m/s}) is a scalar representing magnitude, while velocity is a vector containing both magnitude and direction.
Clarifying vector vs. scalar quantities is required to evaluate motion along a curved trajectory.
2
Analyze the car's direction of travel on the circular track.
As the car follows the curve, the tangent direction of travel continuously turns.
A change in direction constitutes a change in the velocity vector, even when speed remains constant.
3
Determine the resulting acceleration.
Acceleration is the rate of change of velocity (a=Δv/Δta = \Delta v / \Delta t), directed inward toward the center (centripetal acceleration).
An unbalanced inward force is required to alter direction, creating non-zero acceleration.

Anahtar Kavram

Vector nature of velocity and centripetal acceleration in circular motion
Tahmini Süre:1m 0s
Soru 2Soru →

A radar operator tracks a reconnaissance aircraft traveling due east at a constant rate of 450 knots450\text{ knots}. Which of the following physical quantities does this measurement represent?

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Cevap: Velocity, because it specifies both a magnitude and a direction of motion

Cevap

Velocity, because the measurement includes both a numerical magnitude and a directional component.
Velocity is a vector quantity that requires both a magnitude (speed) and an explicit directional heading. Because the radar measurement provides both the rate (450 knots450\text{ knots}) and the direction ('due east'), it represents velocity.

Adım Adım Çözüm

1
Analyze the given physical measurement components
The measurement contains a numerical rate (450 knots450\text{ knots}) and a compass direction (due east).
Determining the correct kinematic quantity requires identifying whether direction is specified alongside magnitude.
2
Distinguish between scalar and vector quantities
Speed is scalar (magnitude only), while velocity is vector (magnitude plus direction).
Since both speed and direction are explicitly stated, the measurement represents velocity.

Anahtar Kavram

Difference between scalar speed and vector velocity in kinematics
Tahmini Süre:40s
Soru 3Soru →

A transport vehicle with a mass of 2000 kg2{}000\text{ kg} travels along a straight, level road at a constant velocity of 20 m/s20\text{ m/s}. The driver applies the brakes, causing the vehicle to decelerate uniformly to a complete stop over a distance of 40 m40\text{ m}. What is the magnitude of the net horizontal braking force acting on the vehicle?

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Cevap: 10000 N10{}000\text{ N}

Cevap

The magnitude of the net horizontal braking force is 10000 N10{}000\text{ N}.
The magnitude of the acceleration is determined by vf2=vi2+2adv_f^2 = v_i^2 + 2ad, yielding a=5 m/s2a = 5\text{ m/s}^2. According to Newton's Second Law (F=maF = ma), multiplying the mass of 2000 kg2{}000\text{ kg} by 5 m/s25\text{ m/s}^2 results in a net braking force of 10000 N10{}000\text{ N}.

Adım Adım Çözüm

1
Calculate the magnitude of uniform acceleration using the kinematic equation relating velocity, acceleration, and displacement: vf2=vi2+2aΔxv_f^2 = v_i^2 + 2a\Delta x.
02=(20 m/s)2+2a(40 m)  ⟹  0=400+80a  ⟹  a=−5 m/s20^2 = (20\text{ m/s})^2 + 2a(40\text{ m}) \implies 0 = 400 + 80a \implies a = -5\text{ m/s}^2. The magnitude of acceleration is 5 m/s25\text{ m/s}^2.
The acceleration must be found from the known initial speed (20 m/s20\text{ m/s}), final speed (0 m/s0\text{ m/s}), and stopping distance (40 m40\text{ m}).
2
Apply Newton's Second Law of Motion (Fnet=maF_{\text{net}} = ma) to find the magnitude of the net horizontal braking force.
Fnet=(2000 kg)(5 m/s2)=10000 NF_{\text{net}} = (2{}000\text{ kg})(5\text{ m/s}^2) = 10{}000\text{ N}.
The net force required to decelerate the mass is the product of mass and acceleration.

Anahtar Kavram

Kinematic equations for uniform deceleration and Newton's Second Law of Motion (F=maF = ma)

Alternatif Yöntem

Find the average velocity vavg=vi+vf2=20+02=10 m/sv_{\text{avg}} = \frac{v_i + v_f}{2} = \frac{20 + 0}{2} = 10\text{ m/s}. The stopping time is t=dvavg=4010=4 st = \frac{d}{v_{\text{avg}}} = \frac{40}{10} = 4\text{ s}. Acceleration is a=Δvt=204=5 m/s2a = \frac{\Delta v}{t} = \frac{20}{4} = 5\text{ m/s}^2, giving F=ma=2000×5=10000 NF = ma = 2{}000 \times 5 = 10{}000\text{ N}.
Tahmini Süre:1m 30s
Soru 4Soru →

A motorized winch pulls an 80 kg80\text{ kg} cargo pallet horizontally from rest across a concrete loading platform. The winch exerts a constant horizontal pulling force of 440 N440\text{ N}, while a constant kinetic friction force of 120 N120\text{ N} opposes the motion. What is the final speed of the pallet in meters per second (m/s\text{m/s}) after being pulled continuously for 5 seconds5\text{ seconds}?

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Cevap: 20

Cevap

20 m/s20\text{ m/s}
The correct speed is 20 m/s20\text{ m/s}. By finding the net unbalanced force (440 N−120 N=320 N440\text{ N} - 120\text{ N} = 320\text{ N}), the acceleration of the 80 kg80\text{ kg} pallet is calculated as a=320/80=4 m/s2a = 320 / 80 = 4\text{ m/s}^2. Multiplying this constant acceleration by the elapsed time of 5 s5\text{ s} yields the final speed of 20 m/s20\text{ m/s}.

Adım Adım Çözüm

1
Determine the net horizontal force acting on the cargo pallet by subtracting the opposing friction force from the applied pulling force.
Fnet=440 N−120 N=320 NF_{\text{net}} = 440\text{ N} - 120\text{ N} = 320\text{ N}
According to Newton's laws of motion, acceleration is produced only by the unbalanced net force acting on the mass.
2
Calculate the constant horizontal acceleration using Newton's second law of motion (a=Fnetma = \frac{F_{\text{net}}}{m}).
a=320 N80 kg=4 m/s2a = \frac{320\text{ N}}{80\text{ kg}} = 4\text{ m/s}^2
The acceleration of an object is directly proportional to the net force and inversely proportional to its mass.
3
Compute the final speed after 5 seconds5\text{ seconds} using the kinematic velocity-time relationship (v=v0+atv = v_0 + at) with an initial speed of 0 m/s0\text{ m/s}.
v=0 m/s+(4 m/s2)(5 s)=20 m/sv = 0\text{ m/s} + (4\text{ m/s}^2)(5\text{ s}) = 20\text{ m/s}
For an object undergoing constant acceleration from rest, final velocity is the product of acceleration and elapsed time.

Anahtar Kavram

Newton's Second Law combined with linear kinematics under constant net force
Tahmini Süre:1m 30s
Soru 5Soru →

A lunar exploration probe has a mass of 60 kg60\text{ kg} on Earth, where gravitational acceleration is 9.8 m/s29.8\text{ m/s}^2. The probe is transported to the Moon, where gravitational acceleration is 1.6 m/s21.6\text{ m/s}^2. A thruster applies a constant horizontal net force of 180 N180\text{ N} to propel the probe along a frictionless test surface. What is the mass of the probe on the Moon, and what is the magnitude of its horizontal acceleration?

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Cevap: The mass is 60 kg60\text{ kg}, and the acceleration is 3.0 m/s23.0\text{ m/s}^2.

Cevap

The probe's mass on the Moon is 60 kg60\text{ kg}, and its horizontal acceleration is 3.0 m/s23.0\text{ m/s}^2.
Mass is a fundamental scalar quantity that measures an object's inertia (resistance to acceleration) and remains constant regardless of the gravitational environment. On the Moon, the probe retains its full mass of 60 kg60\text{ kg}. By Newton's second law of motion, the horizontal acceleration is determined by dividing the net horizontal force by the mass: a=Fm=180 N60 kg=3.0 m/s2a = \frac{F}{m} = \frac{180\text{ N}}{60\text{ kg}} = 3.0\text{ m/s}^2.

Adım Adım Çözüm

1
Determine the mass of the probe on the Moon
The mass remains 60 kg60\text{ kg}.
Mass measures the amount of matter in an object and its inertia; it does not change with the local gravitational field strength.
2
Apply Newton's second law of motion (Fnet=maF_{\text{net}} = ma) to find horizontal acceleration
a=Fnetm=180 N60 kg=3.0 m/s2a = \frac{F_{\text{net}}}{m} = \frac{180\text{ N}}{60\text{ kg}} = 3.0\text{ m/s}^2
The horizontal thrust provides the net horizontal force on a frictionless surface, accelerating the object's mass.

Anahtar Kavram

Mass is an invariant intrinsic property representing inertia, whereas acceleration depends solely on the net applied force divided by that mass according to Newton's Second Law (F=maF = ma).
Tahmini Süre:1m 15s
Soru 6Soru →

In Newtonian mechanics and kinematics, distinct physical parameters govern the translational and curved motion of bodies. Match each mechanical quantity with its precise physical definition and governing mathematical relationship.

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Öğeler

Impulse
Centripetal Acceleration
Kinetic Friction Force
Instantaneous Velocity

Eşleşmeler

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Cevap

Impulse matches the force applied over a time interval causing a change in momentum (J=FavgΔtJ = F_{\text{avg}} \Delta t); Centripetal Acceleration matches the inward rate of directional velocity change on a curve (ac=v2ra_c = \frac{v^2}{r}); Kinetic Friction Force matches the dissipative sliding resistance proportional to normal force (fk=μkFNf_k = \mu_k F_N); and Instantaneous Velocity matches the time rate of change of position (v=drdtv = \frac{d\mathbf{r}}{dt}).
Each mechanics quantity matches its exact standard definition and mathematical formula: Impulse represents force applied across time; Centripetal Acceleration measures inward radial turning acceleration; Kinetic Friction Force calculates contact resistance against sliding; and Instantaneous Velocity specifies the instantaneous vector rate of positional change.

Adım Adım Çözüm

1
Identify the definition and formula for Impulse
Impulse equals FavgΔt=ΔpF_{\text{avg}} \Delta t = \Delta p, representing force integrated over time.
According to the impulse-momentum theorem, impulse measures the total momentum transfer delivered by a force over an elapsed time.
2
Identify the definition and formula for Centripetal Acceleration
Centripetal acceleration equals ac=v2ra_c = \frac{v^2}{r}, oriented radially inward.
In circular and curvilinear dynamics, inward acceleration is required to change velocity direction without necessarily changing tangential speed.
3
Identify the definition and formula for Kinetic Friction Force
Kinetic friction force equals fk=μkFNf_k = \mu_k F_N, opposing relative sliding.
Amontons' and Coulomb's laws of friction state that kinetic friction depends directly on the normal force pressing two surfaces together.
4
Identify the definition and formula for Instantaneous Velocity
Instantaneous velocity equals v=drdtv = \frac{d\mathbf{r}}{dt}, establishing magnitude and directional vector heading.
Velocity is the first derivative of position with respect to time, distinguishing it from scalar speed by including direction.

Anahtar Kavram

Fundamental kinematic definitions and dynamic force-motion relationships in Newtonian mechanics.
Tahmini Süre:1m 30s
Soru 7Soru →

In the study of classical mechanics, fundamental terms describe the motion of objects and their response to forces. Match each mechanics term on the left with its correct scientific definition on the right.

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Öğeler

Velocity
Acceleration
Inertia
Momentum

Eşleşmeler

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Cevap

Velocity corresponds to the rate of change of position in a specified direction; Acceleration corresponds to the rate at which velocity changes over time; Inertia corresponds to an object's resistance to changes in its state of motion; and Momentum corresponds to the product of an object's mass and velocity.
The pairings correctly match each fundamental physical term to its scientific definition: Velocity is position change over time with direction; Acceleration is velocity change over time; Inertia is the intrinsic resistance of matter to motion changes; and Momentum is the product of mass and velocity.

Adım Adım Çözüm

1
Define Velocity
Velocity is displacement divided by elapsed time (v=ΔxΔtv = \frac{\Delta x}{\Delta t}), including direction.
It describes how rapidly an object changes its position in a particular direction.
2
Define Acceleration
Acceleration is the change in velocity divided by time (a=ΔvΔta = \frac{\Delta v}{\Delta t}).
It quantifies speeding up, slowing down, or changing direction.
3
Define Inertia
Inertia is proportional to mass and represents resistance to acceleration.
According to Newton's first law, a body maintains constant velocity unless acted upon by a net external force.
4
Define Momentum
Momentum (pp) is calculated as mass times velocity (p=mvp = mv).
It represents the overall moving mass and determines the impact force needed to bring an object to rest.

Anahtar Kavram

Core kinematic and dynamic quantities in mechanics: velocity, acceleration, inertia, and momentum.
Tahmini Süre:45s
Soru 8Soru →

A model electric car accelerates uniformly along a straight track from rest to a speed of 12 m/s12\text{ m/s} in 4 seconds4\text{ seconds}. What is the magnitude of the car's acceleration in meters per second squared (m/s2\text{m/s}^2)?

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Cevap: 3

Cevap

The magnitude of the acceleration is 3 m/s23\text{ m/s}^2.
Acceleration is defined as the change in velocity divided by the time elapsed (a=Δvta = \frac{\Delta v}{t}). Since the car accelerates from 0 m/s0\text{ m/s} to 12 m/s12\text{ m/s} in 4 s4\text{ s}, the acceleration is 12−04=3 m/s2\frac{12 - 0}{4} = 3\text{ m/s}^2.

Adım Adım Çözüm

1
Identify the given physical quantities from the problem statement
Initial velocity vi=0 m/sv_i = 0\text{ m/s}, final velocity vf=12 m/sv_f = 12\text{ m/s}, time t=4 st = 4\text{ s}
Establishing known variables is necessary before selecting the appropriate kinematic relationship.
2
Apply the definition of constant linear acceleration: a=ΔvΔt=vf−vita = \frac{\Delta v}{\Delta t} = \frac{v_f - v_i}{t}
Formula set up as a=12 m/s−0 m/s4 sa = \frac{12\text{ m/s} - 0\text{ m/s}}{4\text{ s}}
Acceleration represents the rate of change of velocity with respect to time.
3
Perform the division to compute acceleration
a=3 m/s2a = 3\text{ m/s}^2
Dividing 1212 by 44 yields the constant acceleration magnitude.

Anahtar Kavram

Uniform Linear Acceleration

Alternatif Yöntem

Using the kinematic equation vf=vi+atv_f = v_i + at, substitute 12=0+a(4)12 = 0 + a(4), which simplifies directly to 4a=124a = 12, yielding a=3 m/s2a = 3\text{ m/s}^2.
Tahmini Süre:45s
Soru 9Soru →

A 3 kg3\text{ kg} object moving at 20 m/s20\text{ m/s} along a frictionless horizontal surface collides with and sticks to a stationary 7 kg7\text{ kg} object. Immediately after the collision, the combined mass slides onto a rough surface with a coefficient of kinetic friction of 0.30.3. Assuming the acceleration due to gravity is 10 m/s210\text{ m/s}^2, how many meters will the combined mass slide before coming to a complete stop?

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Cevap: 6

Cevap

6
The problem is solved in two phases. Phase 1 is the perfectly inelastic collision, where momentum is conserved: pi=pf⇒(3)(20)=(10)vp_i = p_f \Rightarrow (3)(20) = (10)v, which gives a shared velocity of 6 m/s6\text{ m/s}. Phase 2 is the sliding on a rough surface, where the only horizontal force is kinetic friction. The acceleration is a=−μkg=−(0.3)(10)=−3 m/s2a = -\mu_k g = -(0.3)(10) = -3\text{ m/s}^2. Finally, using the kinematic equation vf2=vi2+2adv_f^2 = v_i^2 + 2ad (where vf=0v_f = 0), we get 0=36+2(−3)d0 = 36 + 2(-3)d, yielding d=6 metersd = 6\text{ meters}.

Adım Adım Çözüm

1
Apply the law of conservation of momentum to find the velocity of the combined mass immediately after the collision.
v=6 m/sv = 6\text{ m/s}
In a perfectly inelastic collision, momentum is conserved (m1v1+m2v2=(m1+m2)vm_1v_1 + m_2v_2 = (m_1+m_2)v). Therefore, 3(20)+7(0)=10v3(20) + 7(0) = 10v.
2
Calculate the deceleration of the combined mass due to kinetic friction.
a=−3 m/s2a = -3\text{ m/s}^2
The net force is kinetic friction (Fk=μkmgF_k = \mu_k m g). Using Newton's second law, acceleration a=−Fk/m=−μkg=−0.3(10)a = -F_k / m = -\mu_k g = -0.3(10).
3
Use kinematics to find the distance required for the mass to come to a stop.
d=6 md = 6\text{ m}
Using the time-independent kinematic equation vf2=vi2+2adv_f^2 = v_i^2 + 2ad with vf=0 m/sv_f = 0\text{ m/s}, vi=6 m/sv_i = 6\text{ m/s}, and a=−3 m/s2a = -3\text{ m/s}^2.

Anahtar Kavram

Conservation of Momentum and Kinematics
Soru 10Soru →

A motorized conveyor system applies a constant horizontal net force of 80 N80\text{ N} to a container, causing it to accelerate along a smooth surface at 4 m/s24\text{ m/s}^2. What is the mass of the container?

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Cevap: 20 kg20\text{ kg}

Cevap

The mass of the container is 20 kg20\text{ kg}.
According to Newton's second law of motion (F=maF = ma), mass is equal to net force divided by acceleration (m=Fam = \frac{F}{a}). Dividing 80 N80\text{ N} by 4 m/s24\text{ m/s}^2 gives 20 kg20\text{ kg}.

Adım Adım Çözüm

1
Identify the given physical quantities and the relevant equation.
Net Force F=80 NF = 80\text{ N}, Acceleration a=4 m/s2a = 4\text{ m/s}^2, and Newton's Second Law is F=maF = ma.
Newton's second law relates net force, mass, and acceleration.
2
Rearrange the equation to solve for mass (mm) and substitute the given values.
m=Fa=80 N4 m/s2=20 kgm = \frac{F}{a} = \frac{80\text{ N}}{4\text{ m/s}^2} = 20\text{ kg}.
Dividing both sides of F=maF = ma by aa isolates the unknown mass mm.

Anahtar Kavram

Newton's Second Law of Motion (F=maF = ma)
Tahmini Süre:45s
Soru 11Soru →

In everyday physical interactions, distinct forces and kinematic principles govern how objects start, change, or cease their motion. Which pairs correctly match each physical observation on the left with its primary governing principle on the right?

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Öğeler

A metal toolbox sliding across a steel deck gradually slows down and stops.
A standing passenger lurches forward when a transport bus suddenly applies its brakes.
A dropped wrench accelerates straight down toward the workshop floor.
A fully loaded cargo cart requires more braking force to stop than an empty cart traveling at the same speed.

Eşleşmeler

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Cevap

The correct pairings match the sliding toolbox with frictional force, the lurching passenger with inertia, the falling wrench with gravitational attraction, and the harder-to-stop loaded cart with momentum.
Each observation directly matches the defining characteristic of its governing principle: surface resistance causing slowing is friction, resistance to change in motion is inertia, downward acceleration is gravity, and mass-dependent difficulty in stopping a moving object is momentum.

Adım Adım Çözüm

1
Analyze the cause of stopping motion for sliding surfaces.
Identify friction as the contact force resisting sliding between the toolbox and deck.
Friction opposes sliding motion parallel to contacting surfaces.
2
Examine the tendency of a passenger to keep moving forward during sudden braking.
Identify inertia as the property of matter resisting changes in velocity.
Newton's First Law explains that objects in motion stay in motion unless acted upon by a net external force.
3
Determine the downward pull on unsupported falling objects.
Identify gravity as the non-contact attractive force pulling mass downward.
Earth's gravity accelerates falling objects toward the ground at approximately 9.8 m/s29.8\text{ m/s}^2.
4
Evaluate why a heavier cart at equal speed is harder to bring to rest.
Identify momentum (p=mvp = mv) as the quantity dependent on mass and speed that dictates stopping effort.
Greater mass at the same speed yields larger momentum, requiring greater impulse to stop.

Anahtar Kavram

Fundamental mechanical principles including friction, inertia, gravity, and momentum governing the motion and interaction of objects.
Tahmini Süre:45s
Soru 12Soru →

A physicist conducts an experiment with a solid block on a perfectly frictionless horizontal track. On Earth, a constant horizontal force of 150 N150\text{ N} applied to the block produces a forward acceleration of 3 m/s23\text{ m/s}^2. If the physicist transports the exact same block and track to an exoplanet where the acceleration due to gravity is exactly one-fifth that of Earth, and applies the identical 150 N150\text{ N} horizontal force, which of the following describes the block's resulting mass and forward acceleration?

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Cevap: The mass remains 50 kg50\text{ kg}, and the acceleration remains 3 m/s23\text{ m/s}^2.

Cevap

The mass remains 50 kg50\text{ kg}, and the acceleration remains 3 m/s23\text{ m/s}^2.
The block's mass is an intrinsic property and remains 50 kg50\text{ kg} regardless of the local gravitational field. Because the track is frictionless, the object's horizontal acceleration is determined solely by the applied horizontal force and its mass (a=F/ma = F/m). Since neither the applied force (150 N150\text{ N}) nor the mass (50 kg50\text{ kg}) changed, the acceleration remains exactly the same at 3 m/s23\text{ m/s}^2.

Adım Adım Çözüm

1
Calculate the mass of the block on Earth using Newton's second law (F=maF = ma).
m=150 N/3 m/s2=50 kgm = 150\text{ N} / 3\text{ m/s}^2 = 50\text{ kg}.
Mass is the ratio of applied net force to the resulting acceleration.
2
Determine the mass of the block on the exoplanet.
The mass remains 50 kg50\text{ kg}.
Mass is an intrinsic property of an object measuring its inertia; it does not change based on the local gravitational field.
3
Calculate the horizontal acceleration on the exoplanet.
a=F/m=150 N/50 kg=3 m/s2a = F / m = 150\text{ N} / 50\text{ kg} = 3\text{ m/s}^2.
On a frictionless horizontal surface, vertical forces (weight and normal force) do not impact horizontal motion. The only horizontal force is the 150 N150\text{ N} applied force, and because the mass is unchanged, the acceleration remains identical.

Anahtar Kavram

Invariance of Mass and Independence of Horizontal Inertia from Gravity
Soru 13Soru →

A remote-controlled toy boat with a mass of 2 kg2\text{ kg} accelerates across a calm pond at a rate of 3 m/s23\text{ m/s}^2. What is the net horizontal force acting on the boat?

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Cevap: 6 N6\text{ N}

Cevap

The net horizontal force acting on the boat is 6 N6\text{ N}.
Newton's second law of motion states that net force equals mass multiplied by acceleration (F=maF = ma). Multiplying the mass of 2 kg2\text{ kg} by the acceleration of 3 m/s23\text{ m/s}^2 yields a net force of 6 N6\text{ N}.

Adım Adım Çözüm

1
Identify the given values from the problem statement.
Mass m=2 kgm = 2\text{ kg} and acceleration a=3 m/s2a = 3\text{ m/s}^2.
Determining the known variables allows the direct application of Newton's second law of motion.
2
Apply the formula for Newton's second law of motion (F=maF = ma).
F=2 kg×3 m/s2=6 NF = 2\text{ kg} \times 3\text{ m/s}^2 = 6\text{ N}.
Multiplying mass in kilograms by acceleration in meters per second squared yields force in newtons (1 N=1 kg⋅m/s21\text{ N} = 1\text{ kg}\cdot\text{m/s}^2).

Anahtar Kavram

Newton's Second Law of Motion (F=maF = ma)
Tahmini Süre:45s
Soru 14Soru →

A science teacher simultaneously drops a steel hammer and a bird feather from the same height inside a sealed vacuum chamber that contains no air. Which of the following best predicts the motion of the two objects?

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Cevap: Both objects will hit the bottom at the exact same time because gravity accelerates all objects at the same rate in the absence of air resistance.

Cevap

Both objects will hit the bottom at the exact same time because gravity accelerates all objects at the same rate in the absence of air resistance.
In the absence of air resistance, the only force acting on falling objects is gravity. Although a heavier object experiences a greater gravitational pull (weight), it also has proportionally greater inertia (resistance to acceleration). As a result of a=Fm=ga = \frac{F}{m} = g, all objects accelerate downward at the constant rate of approximately 9.8 m/s29.8\text{ m/s}^2 on Earth, reaching the surface at the exact same time when released together from the same height.

Adım Adım Çözüm

1
Identify the external forces acting on the objects inside the chamber.
Only the downward force of gravity acts on the objects, as air resistance is zero in a vacuum.
Recognizing the environmental conditions determines whether drag forces affect the fall.
2
Apply Newton's second law of motion (F=maF = ma) to determine acceleration due to gravity.
The acceleration is calculated as a=Fgm=mgm=ga = \frac{F_g}{m} = \frac{mg}{m} = g.
Demonstrates that the mass mm cancels out, proving acceleration is independent of mass.
3
Compare the arrival times of both falling objects released from the same height.
Since both start from rest with identical acceleration gg, both take time t=2hgt = \sqrt{\frac{2h}{g}} to reach the bottom.
Confirms that both items strike the floor simultaneously.

Anahtar Kavram

Acceleration due to gravity in free fall without air resistance
Tahmini Süre:45s
Soru 15Soru →

A 15 kg15\text{ kg} sled slides across a smooth ice rink at a constant velocity of 4 m/s4\text{ m/s}. What is the magnitude of the sled's momentum in kilogram-meters per second (kg⋅m/s\text{kg}\cdot\text{m/s})?

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Cevap: 60

Cevap

60 kg·m/s
Linear momentum is calculated using the formula p=m×vp = m \times v. For an object with a mass of 15 kg15\text{ kg} moving at 4 m/s4\text{ m/s}, the momentum is 15 kg×4 m/s=60 kg⋅m/s15\text{ kg} \times 4\text{ m/s} = 60\text{ kg}\cdot\text{m/s}.

Adım Adım Çözüm

1
Identify the given mass and velocity values.
m=15 kgm = 15\text{ kg} and v=4 m/sv = 4\text{ m/s}
Linear momentum depends directly on an object's mass and its velocity.
2
Apply the momentum formula p=m×vp = m \times v.
p=15 kg×4 m/s=60 kg⋅m/sp = 15\text{ kg} \times 4\text{ m/s} = 60\text{ kg}\cdot\text{m/s}
Multiplying mass by velocity calculates the magnitude of linear momentum.

Anahtar Kavram

Linear momentum is the product of an object's mass and its velocity (p=mvp = mv).
Tahmini Süre:45s
Soru 16Soru →

Match each fundamental physical law of mechanics to the statement that correctly describes it.

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Öğeler

Newton's First Law of Motion
Newton's Second Law of Motion
Newton's Third Law of Motion
Newton's Law of Universal Gravitation

Eşleşmeler

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Cevap

Newton's First Law pairs with the principle that an object maintains constant velocity unless acted on by an external net force; Newton's Second Law pairs with acceleration being proportional to net force and inversely proportional to mass (F=maF = ma); Newton's Third Law pairs with equal and opposite action-reaction forces; Newton's Law of Universal Gravitation pairs with mutual mass-dependent attraction that weakens with distance squared.
Each mechanics law corresponds to its standard scientific definition: the First Law defines inertia (constant velocity without net force), the Second Law establishes the relationship between force, mass, and acceleration (F=maF = ma), the Third Law describes equal and opposite interaction forces between bodies, and the Law of Universal Gravitation defines mutual mass attraction.

Adım Adım Çözüm

1
Identify the principle governing motion when the net force is zero.
This describes inertia, which is Newton's First Law.
An object resists changes to its velocity when no net force acts on it.
2
Identify the formula and relationship linking net force, mass, and acceleration.
This corresponds to F=maF = ma, which is Newton's Second Law.
Acceleration is produced when an unbalanced net force acts upon a given mass.
3
Identify the law governing force interactions between two distinct objects.
This corresponds to action-reaction pairs, which is Newton's Third Law.
Forces always act simultaneously in opposite directions on interacting bodies.
4
Identify the law describing mutual attraction between any two masses across space.
This corresponds to Newton's Law of Universal Gravitation.
Gravitational pull depends directly on the product of masses and inversely on distance squared.

Anahtar Kavram

Newton's Laws of Motion and Gravitation
Tahmini Süre:45s
Soru 17Soru →

A delivery van travels along a circular entrance ramp at a constant speed of 25 mph25\text{ mph}. Why is the vehicle considered to be accelerating even though the speedometer reading remains unchanged?

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Cevap: The direction of travel is constantly changing, which alters the vehicle's velocity.

Cevap

The direction of travel is constantly changing, which alters the vehicle's velocity.
Acceleration is defined in physics as the rate of change of velocity over time. Because velocity is a vector quantity consisting of both speed and direction, an object traveling in a circle is continuously changing its direction. This continuous change in direction means the velocity vector is changing, which produces acceleration directed toward the center of the turn.

Adım Adım Çözüm

1
Define the relationship between speed, velocity, and acceleration
Speed is a scalar quantity (magnitude only), whereas velocity is a vector quantity (both magnitude and direction). Acceleration (aa) is the rate of change of velocity: a=ΔvΔta = \frac{\Delta v}{\Delta t}.
Determining whether an object is accelerating requires evaluating its velocity vector rather than just its scalar speed.
2
Analyze the motion of the vehicle on a curved path
Although the magnitude of the velocity (speed) is steady at 25 mph25\text{ mph}, the direction of travel continuously turns along the curve.
A change in the direction of a vector constitutes a change in velocity.
3
Conclude whether acceleration occurs
Because velocity changes continuously with direction, the vehicle undergoes centripetal acceleration directed toward the center of the curve.
Any non-zero change in velocity over time confirms acceleration.

Anahtar Kavram

Velocity is a vector quantity comprising both magnitude and direction; thus, changing direction at constant speed results in acceleration.
Tahmini Süre:45s
Soru 18Soru →

A motorized winch pulls a cable, accelerating a load from rest (0 m/s0\text{ m/s}) to a final velocity of 18 m/s18\text{ m/s} in 6 seconds6\text{ seconds} at a constant rate. What is the acceleration of the load in meters per second squared (m/s2\text{m/s}^2)?

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Cevap: 3

Cevap

The acceleration of the load is 3 m/s23\text{ m/s}^2.
Acceleration is calculated by dividing the total change in velocity by the elapsed time (a=Δvta = \frac{\Delta v}{t}). Because the load accelerates uniformly from 0 m/s0\text{ m/s} to 18 m/s18\text{ m/s} over 6 s6\text{ s}, the acceleration is 18 m/s−0 m/s6 s=3 m/s2\frac{18\text{ m/s} - 0\text{ m/s}}{6\text{ s}} = 3\text{ m/s}^2.

Adım Adım Çözüm

1
Identify the initial velocity, final velocity, and elapsed time from the given problem.
vi=0 m/sv_i = 0\text{ m/s}, vf=18 m/sv_f = 18\text{ m/s}, and t=6 st = 6\text{ s}
These parameters are required to calculate uniform linear acceleration.
2
Set up the acceleration formula: a=Δvt=vf−vita = \frac{\Delta v}{t} = \frac{v_f - v_i}{t}.
a=18−06a = \frac{18 - 0}{6}
Acceleration represents the rate of change of velocity with respect to time.
3
Perform the division to compute the numerical value.
a=3 m/s2a = 3\text{ m/s}^2
Dividing 18 m/s18\text{ m/s} by 6 s6\text{ s} yields 3 m/s23\text{ m/s}^2.

Anahtar Kavram

Linear acceleration is defined as the change in velocity divided by the time interval over which the change occurs (a=Δvta = \frac{\Delta v}{t}).
Tahmini Süre:45s
Soru 19Soru →

A mechanical crane lifts a cargo container with a mass of 500 kg500\text{ kg} vertically upward. If the crane's cable exerts a constant upward tension of 6400 N6{}400\text{ N} and the acceleration due to gravity is 9.8 m/s29.8\text{ m/s}^2, what is the upward acceleration of the container?

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Cevap: 3 m/s23\text{ m/s}^2

Cevap

3 m/s23\text{ m/s}^2
The container experiences two vertical forces: an upward tension of 6400 N6{}400\text{ N} and a downward gravitational force (weight) of W=mg=500 kg×9.8 m/s2=4900 NW = mg = 500\text{ kg} \times 9.8\text{ m/s}^2 = 4{}900\text{ N}. The net upward force is 6400 N−4900 N=1500 N6{}400\text{ N} - 4{}900\text{ N} = 1{}500\text{ N}. Applying Newton's second law (a=Fnet/ma = F_{\text{net}} / m) gives an acceleration of 1500 N/500 kg=3 m/s21{}500\text{ N} / 500\text{ kg} = 3\text{ m/s}^2.

Adım Adım Çözüm

1
Calculate the downward gravitational force (weight) acting on the container.
W=mg=500 kg×9.8 m/s2=4900 NW = mg = 500\text{ kg} \times 9.8\text{ m/s}^2 = 4{}900\text{ N}
Weight is the force exerted on the mass by gravity.
2
Find the net upward force by subtracting weight from the upward cable tension.
Fnet=Ftension−W=6400 N−4900 N=1500 NF_{\text{net}} = F_{\text{tension}} - W = 6{}400\text{ N} - 4{}900\text{ N} = 1{}500\text{ N}
The acceleration depends on the resultant unbalanced force acting on the object.
3
Apply Newton's second law (a=Fnet/ma = F_{\text{net}} / m) to determine the acceleration.
a=1500 N500 kg=3 m/s2a = \frac{1{}500\text{ N}}{500\text{ kg}} = 3\text{ m/s}^2
Acceleration equals net force divided by total mass.

Anahtar Kavram

Newton's Second Law and Net Vertical Force
Tahmini Süre:1m 0s
Soru 20Soru →

In the study of classical mechanics, various terms describe the motion of bodies and the forces acting upon them. Match each mechanics concept on the left with its correct physical definition on the right.

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Öğeler

Momentum
Acceleration
Inertia
Weight

Eşleşmeler

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Cevap

Momentum corresponds to the product of mass and velocity; Acceleration corresponds to the rate of change of velocity; Inertia corresponds to the resistance to change in motion; Weight corresponds to the gravitational force acting on an object's mass.
Each mechanics term addresses a specific physical property or relationship: Momentum measures the quantity of motion (p=mvp = mv), Acceleration measures how fast velocity changes (a=ΔvΔta = \frac{\Delta v}{\Delta t}), Inertia is the inherent resistance to changes in motion, and Weight is the gravitational force acting on mass (W=mgW = mg).

Adım Adım Çözüm

1
Identify the definition of Momentum
Momentum is mathematically defined as mass multiplied by velocity (p=mvp = mv), which matches the statement regarding the quantity of motion.
Momentum quantifies the kinetic impact and difficulty of stopping a moving object.
2
Identify the definition of Acceleration
Acceleration is the derivative or rate of change of velocity over time (a=ΔvΔta = \frac{\Delta v}{\Delta t}), matching the definition involving changes in speed or direction.
Any vector change in velocity over time constitutes acceleration.
3
Identify the definition of Inertia
Inertia corresponds to Newton's first law concept—the inherent tendency of matter to resist alterations to its motion or rest.
Inertia is a property of mass rather than a force or rate.
4
Identify the definition of Weight
Weight is the gravitational force exerted on a mass (W=mgW = mg), matching the downward planetary force definition.
Unlike invariant mass, weight is a force that changes based on local gravity.

Anahtar Kavram

Distinguishing core classical mechanics concepts: momentum, acceleration, inertia, and weight.
Tahmini Süre:1m 0s
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Mechanics and Motion Alıştırma Soruları — Armed Services Vocational Aptitude Battery (ASVAB) | Examkin