Tüm alıştırma soruları

13931 soru

Soru 4241Soru

Complete the statement below by identifying the correct consonant sound represented by the underlined letter combination in each word.

Aşağıdaki boşlukları doldurun

In the English word 'chef', the digraph 'ch' produces the consonant sound represented phonetically as , whereas in the word 'choir', the digraph 'ch' produces the sound represented as .
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Cevap

In 'chef', the digraph 'ch' represents the consonant sound /ʃ/, while in 'choir', 'ch' represents the consonant sound /k/.
The digraph 'ch' is pronounced as the fricative /ʃ/ (like 'sh') in 'chef' and as the plosive /k/ (hard 'k' sound) in 'choir'.

Adım Adım Çözüm

1
Analyze the pronunciation of the digraph 'ch' in the word 'chef'.
The letters 'ch' in 'chef' produce the voiceless postalveolar fricative sound, transcribed in IPA as /ʃ/.
Words borrowed into English from French (such as 'chef', 'machine', 'chiffon') preserve the /ʃ/ pronunciation for 'ch'.
2
Analyze the pronunciation of the digraph 'ch' in the word 'choir'.
The letters 'ch' in 'choir' produce the voiceless velar plosive sound, transcribed in IPA as /k/.
Words of Greek derivation (such as 'choir', 'school', 'chemist', 'monarch') typically realize the digraph 'ch' as the hard consonant sound /k/.

Anahtar Kavram

Orthographic variations of consonant sounds for the digraph 'ch'
Tahmini Süre:45s
Soru 4242Soru

Match each physical quantity on the left with its correct physical definition and scalar or vector classification on the right.

Soldaki öğeye tıklayın, sonra eşleşen sağdaki öğeye tıklayın

Öğeler

Work Done
Acceleration
Electric Potential
Force

Eşleşmeler

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Cevap

Work Done matches with Scalar quantity defined as the product of force and displacement in the direction of the force; Acceleration matches with Vector quantity defined as the rate of change of velocity with time; Electric Potential matches with Scalar quantity defined as the work done per unit positive charge in bringing it from infinity; Force matches with Vector quantity defined as the rate of change of linear momentum with time.
Work Done matches the scalar definition involving force and displacement. Acceleration matches the vector definition representing rate of change of velocity. Electric Potential matches the scalar definition of work per unit charge. Force matches the vector definition representing rate of change of momentum.

Adım Adım Çözüm

1
Classify each physical quantity as a scalar (has magnitude only) or a vector (has both magnitude and direction).
Work Done and Electric Potential are scalar quantities. Acceleration and Force are vector quantities.
Scalars require only numerical value and unit, whereas vectors require direction to be fully specified.
2
Match each physical quantity with its precise physical definition.
Work Done corresponds to force multiplied by displacement in the line of action; Acceleration corresponds to velocity change per unit time; Electric Potential corresponds to work done per unit charge; Force corresponds to rate of change of momentum.
Each definition uniquely identifies the fundamental physical relationship for that quantity.

Anahtar Kavram

Classification of physical quantities into scalars and vectors based on their directional properties and definitions
Soru 4243Soru

The gravitational force FF between two point masses m1m_1 and m2m_2 separated by a distance rr is expressed by the equation F=Gm1m2r2F = \frac{G m_1 m_2}{r^2}, where GG represents the universal gravitational constant. What is the dimensional formula for GG?

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Cevap: M1L3T2M^{-1} L^3 T^{-2}

Cevap

The dimensional formula for the universal gravitational constant GG is M1L3T2M^{-1} L^3 T^{-2}.
Isolating GG gives G=Fr2m1m2G = \frac{F r^2}{m_1 m_2}. Substituting the fundamental dimensions for force (MLT2M L T^{-2}), distance (LL), and mass (MM) yields (MLT2)(L2)M2=M1L3T2\frac{(M L T^{-2})(L^2)}{M^2} = M^{-1} L^3 T^{-2}.

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1
Make GG the subject of the formula in Newton's law of gravitation.
G=Fr2m1m2G = \frac{F r^2}{m_1 m_2}
To derive the dimensions of GG, isolate it in terms of force, distance, and mass.
2
Substitute fundamental dimensions for force, distance, and mass.
[G] = \frac{[F][r]^2}{[m_1][m_2]} = \frac{(M L T^{-2})(L^2)}{M \cdot M}
Force has dimensions MLT2M L T^{-2}, distance has dimension LL, and mass has dimension MM.
3
Simplify the powers of fundamental dimensions MM, LL, and TT.
[G] = M^{1-2} L^{1+2} T^{-2} = M^{-1} L^3 T^{-2}
Applying exponent rules simplifies the combined base dimensions.

Anahtar Kavram

Dimensions of Physical Constants
Tahmini Süre:1m 15s
Soru 4244Soru

Two point masses are separated by a distance rr and exert a gravitational force FF on each other. If the distance between them is doubled while keeping their masses constant, what is the new gravitational force between them?

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Cevap: F4\frac{F}{4}

Cevap

The new gravitational force between the two masses is F4\frac{F}{4}.
Gravitational force obeys an inverse-square law with respect to distance (F1r2F \propto \frac{1}{r^2}). When separation distance is multiplied by 2, the force decreases by a factor of 22=42^2 = 4, yielding F4\frac{F}{4}.

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1
Write down Newton's Law of Universal Gravitation
F=Gm1m2r2F = \frac{G m_1 m_2}{r^2}
Establish the mathematical relationship governing gravitational force and separation distance.
2
Substitute the new distance r=2rr' = 2r into the gravitational force equation
F=Gm1m2(2r)2=Gm1m24r2F' = \frac{G m_1 m_2}{(2r)^2} = \frac{G m_1 m_2}{4r^2}
Evaluate how doubling the separation distance affects the magnitude of the force.
3
Express the new force FF' in terms of the initial force FF
F=14(Gm1m2r2)=F4F' = \frac{1}{4}\left(\frac{G m_1 m_2}{r^2}\right) = \frac{F}{4}
Relate the calculated force directly to the original force FF.

Anahtar Kavram

Inverse-Square Law of Gravitation
Tahmini Süre:45s
Soru 4245Soru

In an experiment to determine the density of a solid sphere, the mass is measured as (50.0±0.5) g(50.0 \pm 0.5)\text{ g} and the radius is measured as (2.00±0.05) cm(2.00 \pm 0.05)\text{ cm}. What is the percentage error in the calculated density of the sphere?

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Cevap: 8.5

Cevap

The percentage error in the calculated density of the sphere is 8.5%8.5\%.
The density formula ρ=3m4πr3\rho = \frac{3m}{4\pi r^3} dictates that maximum relative error is given by Δρρ=Δmm+3(Δrr)\frac{\Delta \rho}{\rho} = \frac{\Delta m}{m} + 3\left(\frac{\Delta r}{r}\right). Evaluating the percentage errors gives 1.0%1.0\% for mass and 2.5%2.5\% for radius. Summing 1.0%+3(2.5%)1.0\% + 3(2.5\%) yields 8.5%8.5\%.

Adım Adım Çözüm

1
Determine the functional dependence of density on measured quantities.
Density ρ=mV=3m4πr3\rho = \frac{m}{V} = \frac{3m}{4\pi r^3}.
The volume of a sphere of radius rr is V=43πr3V = \frac{4}{3}\pi r^3.
2
Formulate the maximum fractional error relationship.
\frac{\Delta \rho}{\rho} = \frac{\Delta m}{m} + 3\left(\frac{\Delta r}{r}\right).
When combining uncertainties, fractional errors add, and exponents act as multiplying factors.
3
Calculate the percentage error in the mass measurement.
0.550.0×100%=1.0%.\frac{0.5}{50.0} \times 100\% = 1.0\%.
Percentage error in mass is the absolute uncertainty divided by the measured value multiplied by 100%100\%.
4
Calculate the percentage error in the radius measurement.
0.052.00×100%=2.5%.\frac{0.05}{2.00} \times 100\% = 2.5\%.
Percentage error in radius is the absolute uncertainty divided by the measured value multiplied by 100%100\%.
5
Calculate total percentage error in density.
Percentage error = 1.0\% + 3(2.5\%) = 8.5\%.
The radius contributes three times its relative error because volume depends on r3r^3.

Anahtar Kavram

Error propagation in derived quantities involving powers
Soru 4246Soru

Xerophytic plants typically possess a thick waxy cuticle on their leaf surfaces as a morphological adaptation to minimize cuticular transpiration in arid environments.

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Cevap: True

Cevap

The statement is true because a thick waxy cuticle provides an impermeable physical barrier on the leaf epidermis, reducing non-stomatal water loss in plants adapted to dry habitats.
The statement is true because xerophytic plants possess a thick, waxy cuticle over their leaf surfaces specifically to cut down on cuticular water loss and endure prolonged periods of dry conditions.

Adım Adım Çözüm

1
Identify the ecological group and environment described.
The organism is a xerophyte, which lives in arid or drought-prone environments.
Environmental conditions determine the survival pressures acting on the organism.
2
Analyze the function of the thick waxy cuticle.
Wax is hydrophobic and prevents water movement across the epidermal cell layer.
Structural features that limit evaporation conserve limited internal water reserves.
3
Conclude whether this represents an authentic morphological adaptation.
Reducing cuticular transpiration via a thick waxy cuticle is a confirmed morphological adaptation in xerophytic plants.
The factual claim in the statement is fully correct.

Anahtar Kavram

Morphological Adaptations of Xerophytes to Water Conservation
Soru 4247Soru

What is the value of the logarithmic expression 1log312+1log412\frac{1}{\log_3 12} + \frac{1}{\log_4 12}?

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Cevap: 11

Cevap

11
Using the change of base relationship 1logab=logba\frac{1}{\log_a b} = \log_b a, the expression simplifies to log123+log124\log_{12} 3 + \log_{12} 4. By the product rule of logarithms, this equals log12(3×4)=log1212=1\log_{12}(3 \times 4) = \log_{12} 12 = 1.

Adım Adım Çözüm

1
Apply the change of base rule 1logab=logba\frac{1}{\log_a b} = \log_b a to each term.
\frac{1}{\log_3 12} = \log_{12} 3 \quad \text{and} \quad \frac{1}{\log_4 12} = \log_{12} 4
Expressing both terms with a common base of 1212 enables the use of logarithmic laws.
2
Apply the product law of logarithms logbM+logbN=logb(M×N)\log_b M + \log_b N = \log_b (M \times N).
\log_{12} 3 + \log_{12} 4 = \log_{12} (3 \times 4) = \log_{12} 12
The sum of logarithms with identical bases equals the logarithm of the product of their arguments.
3
Simplify log1212\log_{12} 12.
1
The logarithm of any base to itself is always 11 (logaa=1\log_a a = 1).

Anahtar Kavram

Change of Base Property and Logarithm Addition Law
Soru 4248Soru

A solid right circular cone has a base radius of 7 cm7\text{ cm} and a height of 12 cm12\text{ cm}. Taking π=227\pi = \frac{22}{7}, what is the volume of the cone?

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Cevap: 616 cm3616\text{ cm}^3

Cevap

616 cm3616\text{ cm}^3
The correct answer is obtained by applying the standard cone volume formula V=13πr2hV = \frac{1}{3}\pi r^2 h. Substituting r=7r = 7, h=12h = 12, and π=227\pi = \frac{22}{7} yields V=616 cm3V = 616\text{ cm}^3.

Adım Adım Çözüm

1
Identify the formula for the volume of a solid cone.
V=13πr2hV = \frac{1}{3}\pi r^2 h
The volume of a cone is one-third the volume of a cylinder with the same base radius and height.
2
Substitute the given values into the formula.
V=13×227×(7)2×12V = \frac{1}{3} \times \frac{22}{7} \times (7)^2 \times 12
Given r=7 cmr = 7\text{ cm}, h=12 cmh = 12\text{ cm}, and π=227\pi = \frac{22}{7}.
3
Simplify the expression to find the volume.
V=13×227×49×12=22×7×4=616 cm3V = \frac{1}{3} \times \frac{22}{7} \times 49 \times 12 = 22 \times 7 \times 4 = 616\text{ cm}^3
Simplifying 497=7\frac{49}{7} = 7 and 123=4\frac{12}{3} = 4 leaves 22×7×422 \times 7 \times 4.

Anahtar Kavram

Volume of a Right Circular Cone
Tahmini Süre:45s
Soru 4249Soru

The test scores of five students in a mathematics quiz are 5,8,11,12,5, 8, 11, 12, and 1414. What is the variance of these test scores?

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Cevap: 1010

Cevap

The variance of the test scores is 1010.
The mean of the scores is 1010. Subtracting 1010 from each score gives deviations of 5,2,1,2,-5, -2, 1, 2, and 44. Squaring these gives 25,4,1,4,25, 4, 1, 4, and 1616, which sum to 5050. Dividing this sum by the number of data points (55) yields a variance of 1010.

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1
Calculate the mean (xˉ\bar{x}) of the data set
xˉ=5+8+11+12+145=505=10\bar{x} = \frac{5 + 8 + 11 + 12 + 14}{5} = \frac{50}{5} = 10
The mean is required to find the deviation of each score from the central value.
2
Compute the squared deviations from the mean (xixˉ)2(x_i - \bar{x})^2
(510)2=25(5-10)^2 = 25, (810)2=4(8-10)^2 = 4, (1110)2=1(11-10)^2 = 1, (1210)2=4(12-10)^2 = 4, (1410)2=16(14-10)^2 = 16
Squaring deviations ensures all negative differences become positive.
3
Find the sum of all squared deviations
\sum (x_i - \bar{x})^2 = 25 + 4 + 1 + 4 + 16 = 50
Summing the squared deviations measures total variation around the mean.
4
Divide the total sum of squared deviations by the number of data values (N=5N = 5)
\text{Variance } (\sigma^2) = \frac{50}{5} = 10
Variance is defined as the average of the squared deviations.

Anahtar Kavram

Variance of Ungrouped Data
Tahmini Süre:1m 30s
Soru 4250Soru

Given the universal set E={1,2,3,4,5,6,7,8,9,10}\mathcal{E} = \{1, 2, 3, 4, 5, 6, 7, 8, 9, 10\}, set A={1,2,4,5,8}A = \{1, 2, 4, 5, 8\}, and set B={2,3,5,7,9}B = \{2, 3, 5, 7, 9\}, what is (AB)(A \cup B)'?

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Cevap: {6,10}\{6, 10\}

Cevap

The set {6,10}\{6, 10\}
Combining set AA and set BB gives AB={1,2,3,4,5,7,8,9}A \cup B = \{1, 2, 3, 4, 5, 7, 8, 9\}. The complement (AB)(A \cup B)' contains the elements of the universal set E\mathcal{E} that are not in this union, which are 66 and 1010, giving {6,10}\{6, 10\}.

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1
Find the union of set AA and set BB (ABA \cup B)
AB={1,2,3,4,5,7,8,9}A \cup B = \{1, 2, 3, 4, 5, 7, 8, 9\}
The union combines all distinct elements present in set AA, set BB, or both.
2
Determine the complement of (AB)(A \cup B) with respect to the universal set E\mathcal{E}
(AB)=E(AB)={6,10}(A \cup B)' = \mathcal{E} \setminus (A \cup B) = \{6, 10\}
The complement consists of all elements in the universal set E\mathcal{E} that are not present in ABA \cup B.

Anahtar Kavram

Set Union and Set Complement
Soru 4251Soru

A simple pendulum suspended in a terrestrial laboratory has a period of oscillation TT when fitted with a bob of mass mm. If the bob is replaced by another bob of mass 4m4m and the entire setup is moved to a high-altitude station where the acceleration due to gravity is g4\frac{g}{4}, what is the new period of oscillation of the pendulum?

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Cevap: 2T2T

Cevap

The new period of oscillation is 2T2T.
The period of a simple pendulum is given by T=2πLgT = 2\pi \sqrt{\frac{L}{g}}. It depends strictly on the length of the string LL and the local gravitational acceleration gg, making it independent of the bob's mass mm. Replacing mass mm with 4m4m does not alter the period. When gravity decreases to g=g4g' = \frac{g}{4}, the new period becomes T=2πLg/4=2(2πLg)=2TT' = 2\pi \sqrt{\frac{L}{g/4}} = 2 \left(2\pi \sqrt{\frac{L}{g}}\right) = 2T.

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1
Identify the formula for the period of a simple pendulum
The period TT of a simple pendulum is given by T=2πLgT = 2\pi \sqrt{\frac{L}{g}}, where LL is the pendulum length and gg is the acceleration due to gravity.
This formula defines how physical parameters affect the oscillatory period of a pendulum under simple harmonic motion.
2
Analyze the effect of changing the bob's mass
Changing the mass of the bob from mm to 4m4m has no effect on the period.
The equation for the period of a simple pendulum contains no mass term, demonstrating that mass does not influence the period of small-angle oscillations.
3
Calculate the new period TT' under the altered gravitational field g=g4g' = \frac{g}{4}
T=2πLg/4=2π4Lg=2×(2πLg)=2TT' = 2\pi \sqrt{\frac{L}{g/4}} = 2\pi \sqrt{\frac{4L}{g}} = 2 \times \left(2\pi \sqrt{\frac{L}{g}}\right) = 2T.
Reducing the gravitational acceleration to one-fourth increases the square-root term 11/4=2\sqrt{\frac{1}{1/4}} = 2, thereby doubling the period.

Anahtar Kavram

Mass Independence and Gravity Dependence of Simple Pendulum Period
Soru 4252Soru

A straight line LL passes through the point (4,2)(4, -2) and is perpendicular to the line defined by the equation 3x2y+8=03x - 2y + 8 = 0. What is the yy-intercept of line LL?

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Cevap: 23\frac{2}{3}

Cevap

The yy-intercept of line LL is 23\frac{2}{3}.
The given line 3x2y+8=03x - 2y + 8 = 0 has a gradient of 32\frac{3}{2}. A perpendicular line must have a gradient equal to the negative reciprocal, which is 23-\frac{2}{3}. Substituting the point (4,2)(4, -2) into yy1=m(xx1)y - y_1 = m(x - x_1) gives y+2=23(x4)y + 2 = -\frac{2}{3}(x - 4), which simplifies to y=23x+23y = -\frac{2}{3}x + \frac{2}{3}. Setting x=0x = 0 yields the yy-intercept of 23\frac{2}{3}.

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1
Find the gradient of the given line.
Expressing 3x2y+8=03x - 2y + 8 = 0 in slope-intercept form y=mx+cy = mx + c gives 2y=3x+8    y=32x+42y = 3x + 8 \implies y = \frac{3}{2}x + 4. The gradient m1=32m_1 = \frac{3}{2}.
The gradient of the given line is required to determine the slope of line LL.
2
Determine the gradient of line LL.
Since line LL is perpendicular to the given line, mL=1m1=13/2=23m_L = -\frac{1}{m_1} = -\frac{1}{3/2} = -\frac{2}{3}.
Perpendicular lines have gradients whose product is 1-1 (m1mL=1m_1 \cdot m_L = -1).
3
Find the equation of line LL using point-slope form.
Using (x1,y1)=(4,2)(x_1, y_1) = (4, -2) and mL=23m_L = -\frac{2}{3}:
yy1=mL(xx1)y - y_1 = m_L(x - x_1)
y(2)=23(x4)y - (-2) = -\frac{2}{3}(x - 4)
y+2=23x+83y + 2 = -\frac{2}{3}x + \frac{8}{3}
y=23x+832y = -\frac{2}{3}x + \frac{8}{3} - 2
y=23x+23y = -\frac{2}{3}x + \frac{2}{3}
To find the yy-intercept, we need the complete equation of line LL.
4
Identify the yy-intercept.
Comparing y=23x+23y = -\frac{2}{3}x + \frac{2}{3} to y=mx+cy = mx + c, the yy-intercept c=23c = \frac{2}{3}.
The constant term cc in y=mx+cy = mx + c represents the yy-intercept.

Anahtar Kavram

Perpendicular lines in coordinate geometry have gradients that are negative reciprocals of each other (m1m2=1m_1 \cdot m_2 = -1).
Soru 4253Soru

What is the indefinite integral (3x2+4cosx)dx\int (3x^2 + 4\cos x) \, dx?

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Cevap: x3+4sinx+Cx^3 + 4\sin x + C

Cevap

x3+4sinx+Cx^3 + 4\sin x + C
Integrating 3x23x^2 gives x3x^3 via the power rule, and integrating 4cosx4\cos x gives 4sinx4\sin x. Combining these terms along with the required constant of integration CC results in x3+4sinx+Cx^3 + 4\sin x + C.

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1
Integrate the polynomial term 3x23x^2 using the power rule xndx=xn+1n+1\int x^n dx = \frac{x^{n+1}}{n+1}.
3x2dx=3x33=x3\int 3x^2 dx = \frac{3x^3}{3} = x^3
The power rule increases the exponent by 1 and divides by the new exponent.
2
Integrate the trigonometric term 4cosx4\cos x using the standard integral cosxdx=sinx\int \cos x \, dx = \sin x.
4cosxdx=4sinx\int 4\cos x \, dx = 4\sin x
The antiderivative of cosine is positive sine.
3
Combine the results and append the constant of integration CC.
x3+4sinx+Cx^3 + 4\sin x + C
All indefinite integrals must include an arbitrary constant CC.

Anahtar Kavram

Indefinite Integration of Polynomial and Trigonometric Functions
Soru 4254Soru

A point PP lies inside a circle of radius 13 cm13\text{ cm} at a distance of 5 cm5\text{ cm} from the center OO. A chord ABAB passes through point PP such that the ratio of segment APAP to segment PBPB is 1:41:4. Calculate the total length of the chord ABAB in centimeters.

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Cevap: 30

Cevap

The total length of chord ABAB is 30 cm30\text{ cm}.
Using the Power of a Point property for an interior point PP, the product of the chord segments is APPB=R2OP2=13252=144AP \cdot PB = R^2 - OP^2 = 13^2 - 5^2 = 144. Given AP:PB=1:4AP : PB = 1 : 4, we write AP=xAP = x and PB=4xPB = 4x, leading to 4x2=144    x=6 cm4x^2 = 144 \implies x = 6\text{ cm}. Summing the two segments gives AB=6+24=30 cmAB = 6 + 24 = 30\text{ cm}.

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1
Calculate the constant product of chord segments passing through interior point PP.
APPB=R2OP2=13252=16925=144AP \cdot PB = R^2 - OP^2 = 13^2 - 5^2 = 169 - 25 = 144.
By the intersecting chords theorem, the product of segments created by an interior point PP on any chord equals (Rd)(R+d)=R2d2(R - d)(R + d) = R^2 - d^2.
2
Set up an algebraic equation using the segment ratio AP:PB=1:4AP : PB = 1 : 4.
Let AP=xAP = x and PB=4xPB = 4x, giving (x)(4x)=144    4x2=144(x)(4x) = 144 \implies 4x^2 = 144.
Expressing both chord segments in terms of a single variable xx allows direct calculation of the segment lengths.
3
Solve for xx to find the individual segment lengths.
x2=36    x=6 cmx^2 = 36 \implies x = 6\text{ cm}. Therefore, AP=6 cmAP = 6\text{ cm} and PB=24 cmPB = 24\text{ cm}.
Taking the positive square root gives the scale factor xx since physical distances must be positive.
4
Sum the segment lengths to find the total chord length.
AB=AP+PB=6+24=30 cmAB = AP + PB = 6 + 24 = 30\text{ cm}.
The entire chord length is the sum of its two divided parts.

Anahtar Kavram

Intersecting Chords Theorem and Power of an Interior Point
Soru 4255Soru

A particle executes simple harmonic motion along a straight line with an amplitude of 0.10 m0.10\text{ m}. At what displacement from the equilibrium position is the kinetic energy of the particle equal to three times its potential energy?

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Cevap: 0.05 m0.05\text{ m}

Cevap

The displacement from the equilibrium position is 0.05 m0.05\text{ m}.
In simple harmonic motion, potential energy is U=12kx2U = \frac{1}{2}kx^2 and kinetic energy is K=12k(A2x2)K = \frac{1}{2}k(A^2 - x^2). Equating K=3UK = 3U yields A2x2=3x2A^2 - x^2 = 3x^2, which simplifies to 4x2=A24x^2 = A^2 or x=A2x = \frac{A}{2}. For an amplitude of 0.10 m0.10\text{ m}, the displacement is 0.05 m0.05\text{ m}.

Adım Adım Çözüm

1
Write the expressions for kinetic energy KK and potential energy UU in simple harmonic motion.
U=12kx2U = \frac{1}{2} k x^2 and K=12k(A2x2)K = \frac{1}{2} k (A^2 - x^2), where AA is amplitude and xx is displacement.
These equations express the energy distribution at any displacement xx.
2
Set up the condition given in the problem, K=3UK = 3U.
12k(A2x2)=3×(12kx2)    A2x2=3x2\frac{1}{2} k (A^2 - x^2) = 3 \times \left(\frac{1}{2} k x^2\right) \implies A^2 - x^2 = 3x^2.
Canceling common factor 12k\frac{1}{2} k simplifies the relationship between amplitude and displacement.
3
Solve for displacement xx in terms of amplitude AA.
A2=4x2    x=A2A^2 = 4x^2 \implies x = \frac{A}{2}.
Taking the square root of both sides gives the position where kinetic energy is three times potential energy.
4
Substitute the given amplitude A=0.10 mA = 0.10\text{ m} to find xx.
x=0.10 m2=0.05 mx = \frac{0.10\text{ m}}{2} = 0.05\text{ m}.
Carrying out the calculation yields the final numerical displacement.

Anahtar Kavram

Conservation of Energy in Simple Harmonic Motion
Tahmini Süre:1m 15s
Soru 4256Soru

Given that the determinant of the 3×33 \times 3 matrix M=(3102x1042)M = \begin{pmatrix} 3 & 1 & 0 \\ 2 & x & -1 \\ 0 & 4 & 2 \end{pmatrix} is equal to 2020, calculate the value of xx.

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Cevap: 2

Cevap

The value of xx is 22.
Expanding the matrix MM along its top row yields det(M)=3(2x+4)1(4)=6x+8\det(M) = 3(2x + 4) - 1(4) = 6x + 8. Setting this expression equal to 2020 gives 6x+8=206x + 8 = 20, which simplifies to 6x=126x = 12, yielding x=2x = 2.

Adım Adım Çözüm

1
Expand the 3x3 matrix along the first row
\det(M) = 3(2x - (-4)) - 1(4 - 0) + 0
Cofactor expansion along a row containing a zero simplifies the computation of a 3x3 determinant.
2
Simplify the algebraic expression for the determinant
\det(M) = 6x + 8
Distribute the coefficients and combine like constant terms.
3
Solve the linear equation for x
x = 2
Subtract 8 from 20 to get 12, then divide by 6.

Anahtar Kavram

Determinant of a 3x3 Matrix via Cofactor Expansion
Soru 4257Soru

A body accelerates uniformly from rest at a rate of 4 m/s24\text{ m/s}^2 for 6 s6\text{ s}. What is the distance covered by the body during this time interval?

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Cevap: 72 m72\text{ m}

Cevap

The distance covered by the body is 72 m72\text{ m}.
Applying the equation of motion s=ut+12at2s = ut + \frac{1}{2}at^2 with u=0 m/su = 0\text{ m/s}, a=4 m/s2a = 4\text{ m/s}^2, and t=6 st = 6\text{ s} yields s=0+12(4)(62)=72 ms = 0 + \frac{1}{2}(4)(6^2) = 72\text{ m}.

Adım Adım Çözüm

1
Identify the given kinematic parameters
Initial velocity u=0 m/su = 0\text{ m/s}, acceleration a=4 m/s2a = 4\text{ m/s}^2, and time interval t=6 st = 6\text{ s}.
Since the body starts from rest, its initial velocity is zero.
2
Select and set up the equation of motion for displacement
s=ut+12at2=(0)(6)+12(4)(6)2s = ut + \frac{1}{2}at^2 = (0)(6) + \frac{1}{2}(4)(6)^2
This formula directly relates displacement to initial velocity, acceleration, and time under constant acceleration.
3
Calculate the total distance
s=12×4×36=72 ms = \frac{1}{2} \times 4 \times 36 = 72\text{ m}
Squaring 6 s6\text{ s} yields 36 s236\text{ s}^2, and multiplying by 2 m/s22\text{ m/s}^2 gives 72 m72\text{ m}.

Anahtar Kavram

Linear motion under uniform acceleration
Tahmini Süre:45s
Soru 4258Soru

A body is released from rest from the top of a cliff of height hh. If it covers a distance equal to 716h\frac{7}{16}h in the final second of its motion before hitting the ground, what is the total height hh of the cliff? (Take acceleration due to gravity g=10 m s2g = 10\text{ m s}^{-2})

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Cevap: 80 m80\text{ m}

Cevap

80 m80\text{ m}
Using the equation of motion under constant acceleration, the total distance fallen from rest in time tt is h=12gt2h = \frac{1}{2}gt^2. The distance fallen up to time (t1)(t-1) is ht1=12g(t1)2h_{t-1} = \frac{1}{2}g(t-1)^2. The distance traveled during the final second is Δh=hht1=12g(2t1)\Delta h = h - h_{t-1} = \frac{1}{2}g(2t-1). Equating this to 716h\frac{7}{16}h yields 12g(2t1)=716(12gt2)\frac{1}{2}g(2t-1) = \frac{7}{16}\left(\frac{1}{2}gt^2\right), which simplifies to 7t232t+16=07t^2 - 32t + 16 = 0. Factoring gives t=4 st = 4\text{ s} (rejecting t=47 st = \frac{4}{7}\text{ s} since time must exceed 1 s1\text{ s}). Substituting t=4 st = 4\text{ s} into h=12(10)(4)2h = \frac{1}{2}(10)(4)^2 gives 80 m80\text{ m}.

Adım Adım Çözüm

1
Express total height hh in terms of total fall time tt.
h=12gt2=5t2h = \frac{1}{2} g t^2 = 5t^2
Since the body starts from rest (u=0 m s1u = 0\text{ m s}^{-1}), displacement under uniform acceleration g=10 m s2g = 10\text{ m s}^{-2} is given by h=12gt2h = \frac{1}{2}gt^2.
2
Express the height fallen in the first (t1)(t - 1) seconds.
h=12g(t1)2=5(t1)2h' = \frac{1}{2} g (t - 1)^2 = 5(t - 1)^2
The distance covered up to one second before impact is the total distance fallen minus the distance covered in the final second.
3
Calculate the distance fallen in the final second and set up the equation.
Δh=hh=5t25(t1)2=5(2t1)\Delta h = h - h' = 5t^2 - 5(t - 1)^2 = 5(2t - 1). Given Δh=716h\Delta h = \frac{7}{16}h, we have 5(2t1)=716(5t2)5(2t - 1) = \frac{7}{16}(5t^2).
The distance fallen during the last second is the difference between total height and height fallen up to (t1)(t-1) seconds.
4
Solve the quadratic equation for tt.
7t232t+16=0    (7t4)(t4)=0    t=4 s7t^2 - 32t + 16 = 0 \implies (7t - 4)(t - 4) = 0 \implies t = 4\text{ s} (since t>1 st > 1\text{ s}).
Simplifying 2t1=716t22t - 1 = \frac{7}{16}t^2 gives 7t232t+16=07t^2 - 32t + 16 = 0. The root t=4/7 st = 4/7\text{ s} is discarded as tt must be greater than 1 s1\text{ s}.
5
Substitute t=4 st = 4\text{ s} back into the total height formula.
h=5(4)2=80 mh = 5(4)^2 = 80\text{ m}.
Calculating total height using h=5t2h = 5t^2 for t=4 st = 4\text{ s} gives 80 m80\text{ m}.

Anahtar Kavram

Free Fall under Gravity and Motion in the nn-th Second
Soru 4259Soru

What is the equation of the locus of a point P(x,y)P(x, y) that moves in a plane such that its distance from the origin (0,0)(0,0) is always 5 units?

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Cevap: x^2 + y^2 = 25; x^2+y^2=25; x²+y²=25

Cevap

x2+y2=25x^2 + y^2 = 25
By definition, the locus of a point moving at a fixed distance of 5 units from the origin (0,0)(0,0) is a circle centered at (0,0)(0,0) with radius 5. Substituting into the standard circle equation x2+y2=r2x^2 + y^2 = r^2 yields x2+y2=52=25x^2 + y^2 = 5^2 = 25.

Adım Adım Çözüm

1
Apply the distance formula between a general point P(x,y)P(x, y) and the origin (0,0)(0,0).
d=(x0)2+(y0)2=x2+y2d = \sqrt{(x - 0)^2 + (y - 0)^2} = \sqrt{x^2 + y^2}
The distance between two points (x1,y1)(x_1, y_1) and (x2,y2)(x_2, y_2) is (x2x1)2+(y2y1)2\sqrt{(x_2-x_1)^2 + (y_2-y_1)^2}.
2
Equate the distance formula to the given fixed distance of 5 units and square both sides.
x2+y2=5    x2+y2=25\sqrt{x^2 + y^2} = 5 \implies x^2 + y^2 = 25
Squaring both sides eliminates the square root to give the algebraic equation of the locus.

Anahtar Kavram

The locus of points at a constant distance rr from a fixed point (h,k)(h, k) forms a circle with equation (xh)2+(yk)2=r2(x-h)^2 + (y-k)^2 = r^2.
Tahmini Süre:45s
Soru 4260Soru

A solid object of volume 0.002 m30.002\text{ m}^3 is completely immersed in water of density 1000 kg/m31000\text{ kg/m}^3. What is the magnitude of the upthrust exerted on the object by the water? [Take g=10 m/s2g = 10\text{ m/s}^2]

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Cevap: 20

Cevap

The magnitude of the upthrust exerted on the object is 20 N20\text{ N}.
According to Archimedes' principle, any body completely or partially submerged in a fluid experiences an upward force (upthrust) equal to the weight of the fluid displaced. The weight of the displaced fluid is calculated using U=VρgU = V \cdot \rho \cdot g. Substituting V=0.002 m3V = 0.002\text{ m}^3, ρ=1000 kg/m3\rho = 1000\text{ kg/m}^3, and g=10 m/s2g = 10\text{ m/s}^2 yields U=0.002×1000×10=20 NU = 0.002 \times 1000 \times 10 = 20\text{ N}.

Adım Adım Çözüm

1
Identify the given quantities from the problem statement.
V=0.002 m3V = 0.002\text{ m}^3, ρ=1000 kg/m3\rho = 1000\text{ kg/m}^3, and g=10 m/s2g = 10\text{ m/s}^2.
These are the essential inputs required to calculate the weight of the displaced liquid.
2
Apply Archimedes' principle to find upthrust force.
U=Vρg=0.002×1000×10=20 NU = V \rho g = 0.002 \times 1000 \times 10 = 20\text{ N}.
Archimedes' principle states that the upthrust force equals the weight of the fluid displaced by the object.

Anahtar Kavram

Archimedes' Principle and Upthrust
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