Tüm alıştırma soruları

1526 soru

Soru 561Soru

Find the positive integer value of xx that satisfies the logarithmic equation xlog3x=81x3x^{\log_3 x} = 81x^3.

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Cevap: 81

Cevap

The positive integer value of xx is 81.
Taking the logarithm base 3 on both sides transforms xlog3x=81x3x^{\log_3 x} = 81x^3 into (log3x)2=4+3log3x(\log_3 x)^2 = 4 + 3\log_3 x. Substituting u=log3xu = \log_3 x yields the quadratic equation u23u4=0u^2 - 3u - 4 = 0, which factors as (u4)(u+1)=0(u-4)(u+1) = 0. The roots are u=4u = 4 (x=34=81x = 3^4 = 81) and u=1u = -1 (x=31=1/3x = 3^{-1} = 1/3). Since xx must be a positive integer, the correct value is 81.

Adım Adım Çözüm

1
Take logarithm base 3 of both sides of the equation xlog3x=81x3x^{\log_3 x} = 81x^3
log3(xlog3x)=log3(81x3)\log_3(x^{\log_3 x}) = \log_3(81x^3)
Taking the logarithm with base 3 allows us to simplify the exponent containing log3x\log_3 x.
2
Apply logarithmic identities logb(ak)=klogba\log_b(a^k) = k \log_b a and logb(mn)=logbm+logbn\log_b(mn) = \log_b m + \log_b n
(log3x)2=log381+3log3x=4+3log3x(\log_3 x)^2 = \log_3 81 + 3\log_3 x = 4 + 3\log_3 x
Expanding the products and powers reduces the equation into a single logarithmic variable log3x\log_3 x.
3
Substitute u=log3xu = \log_3 x to create a quadratic equation
u23u4=0u^2 - 3u - 4 = 0
Setting u=log3xu = \log_3 x converts the equation into standard quadratic form.
4
Factor the quadratic expression
(u4)(u+1)=0    u=4 or u=1(u - 4)(u + 1) = 0 \implies u = 4 \text{ or } u = -1
Factoring allows us to find all possible real values for uu.
5
Convert back to xx using x=3ux = 3^u and select the positive integer root
x=34=81x = 3^4 = 81 or x=31=13x = 3^{-1} = \frac{1}{3}. The positive integer solution is x=81x = 81.
The question specifically requests the positive integer solution, eliminating x=13x = \frac{1}{3}.

Anahtar Kavram

Solving equations with variable exponents by taking logarithms and reducing to a quadratic form.
Soru 562Soru

A sample of nitrogen gas enclosed in a constant-volume container exerts a pressure of 2.50 atm2.50\text{ atm} at a temperature of 23C-23^\circ\text{C}. To what temperature, in degrees Celsius (C^\circ\text{C}), must the gas be heated so that its pressure increases to 4.00 atm4.00\text{ atm}?

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Cevap: 127

Cevap

The gas must be heated to 127C127^\circ\text{C}.
According to Gay-Lussac's Pressure Law, for a fixed mass of gas at constant volume, pressure is directly proportional to absolute temperature (PTP \propto T). Converting 23C-23^\circ\text{C} to Kelvin gives 250 K250\text{ K}. Solving 2.50250=4.00T2\frac{2.50}{250} = \frac{4.00}{T_2} gives T2=400 KT_2 = 400\text{ K}. Converting back to Celsius (400273400 - 273) yields the correct temperature of 127C127^\circ\text{C}.

Adım Adım Çözüm

1
Convert the initial temperature from Celsius to the thermodynamic temperature scale (Kelvin).
T1=23+273=250 KT_1 = -23 + 273 = 250\text{ K}
Gas laws strictly require temperature to be expressed in Kelvin.
2
Use Gay-Lussac's Pressure Law equation P1T1=P2T2\frac{P_1}{T_1} = \frac{P_2}{T_2} to solve for T2T_2.
T2=P2×T1P1=4.00×2502.50=400 KT_2 = \frac{P_2 \times T_1}{P_1} = \frac{4.00 \times 250}{2.50} = 400\text{ K}
At constant volume, the pressure of a given mass of gas is directly proportional to its absolute temperature.
3
Convert the calculated temperature T2T_2 back to degrees Celsius.
t2=400273=127Ct_2 = 400 - 273 = 127^\circ\text{C}
The question explicitly requests the final temperature in degrees Celsius.

Anahtar Kavram

Pressure Law (Gay-Lussac's Law)
Soru 563Soru

The speed vv of a longitudinal wave propagating through a gas depends on the pressure PP of the gas and its density ρ\rho according to the dimensional relationship v=CPxρyv = C P^x \rho^y, where CC is a dimensionless constant. Using dimensional analysis, what is the numerical value of xyx - y?

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Cevap: 1

Cevap

The numerical value of xyx - y is 1.0.
By applying the principle of dimensional homogeneity, the exponents are determined as x=0.5x = 0.5 (for pressure) and y=0.5y = -0.5 (for density). Thus, xy=0.5(0.5)=1.0x - y = 0.5 - (-0.5) = 1.0.

Adım Adım Çözüm

1
Determine the dimensions of speed, pressure, and density.
[v]=[LT1][v] = [L T^{-1}], [P]=[ML1T2][P] = [M L^{-1} T^{-2}], and [ρ]=[ML3][\rho] = [M L^{-3}].
Dimensional homogeneity requires expressed physical quantities to be broken down into fundamental dimensions (MM, LL, TT).
2
Substitute dimensions into the relationship v=CPxρyv = C P^x \rho^y.
[LT1]=[ML1T2]x[ML3]y=Mx+yLx3yT2x[L T^{-1}] = [M L^{-1} T^{-2}]^x \, [M L^{-3}]^y = M^{x+y} \, L^{-x-3y} \, T^{-2x}.
This establishes a system of algebraic equations by equating exponents of corresponding fundamental dimensions.
3
Solve for exponents xx and yy.
From time TT: 2x=1    x=0.5-2x = -1 \implies x = 0.5. From mass MM: x+y=0    y=0.5x + y = 0 \implies y = -0.5.
Equating the powers of fundamental dimensions on both sides yields the values of xx and yy.
4
Calculate the required expression (xy)(x - y).
xy=0.5(0.5)=1.0x - y = 0.5 - (-0.5) = 1.0.
Subtracting negative 0.50.5 from 0.50.5 results in 1.01.0.

Anahtar Kavram

Dimensional Analysis and Homogeneity
Soru 564Soru

A naturally occurring sample of boron consists of two stable isotopes, 10B^{10}\text{B} and 11B^{11}\text{B}. If the relative percentage abundance of 10B^{10}\text{B} is 20.0%20.0\% and that of 11B^{11}\text{B} is 80.0%80.0\%, what is the relative atomic mass of boron?

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Cevap: 10.8

Cevap

The relative atomic mass of boron is 10.810.8.
The relative atomic mass of an element is defined as the weighted average mass of its naturally occurring isotopes relative to 112th\frac{1}{12}\text{th} the mass of a carbon-12 atom. Applying the formula RAM=(isotopic mass×% abundance)100\text{RAM} = \frac{\sum (\text{isotopic mass} \times \% \text{ abundance})}{100}, we get (10×20)+(11×80)100=200+880100=10.8\frac{(10 \times 20) + (11 \times 80)}{100} = \frac{200 + 880}{100} = 10.8.

Adım Adım Çözüm

1
Determine the mass contribution of the 10B^{10}\text{B} isotope
10×0.20=2.010 \times 0.20 = 2.0
The weighted contribution of an isotope is its mass multiplied by its fractional abundance.
2
Determine the mass contribution of the 11B^{11}\text{B} isotope
11×0.80=8.811 \times 0.80 = 8.8
The weighted contribution of the second isotope is calculated using its percentage abundance.
3
Sum the weighted contributions to find the relative atomic mass
2.0+8.8=10.82.0 + 8.8 = 10.8
The relative atomic mass of an element is the weighted average mass of all naturally occurring isotopes relative to carbon-12.

Anahtar Kavram

Calculation of Relative Atomic Mass from Isotopic Abundances
Soru 565Soru

Two sound waves of frequencies 440 Hz440\text{ Hz} and 445 Hz445\text{ Hz} travel through air and superpose to produce beats. What is the resulting beat frequency, in hertz?

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Cevap: 5

Cevap

The beat frequency produced by the superposition of the two sound waves is 5 Hz5\text{ Hz}.
When two waves of slightly different frequencies interfere, periodic variations in sound intensity called beats occur. The number of beats heard per second is equal to the absolute difference between the frequencies of the two superposing waves: fbeat=f2f1=445 Hz440 Hz=5 Hzf_{\text{beat}} = |f_2 - f_1| = |445\text{ Hz} - 440\text{ Hz}| = 5\text{ Hz}.

Adım Adım Çözüm

1
Identify the frequencies of the interfering waves
f1=440 Hzf_1 = 440\text{ Hz} and f2=445 Hzf_2 = 445\text{ Hz}
Beat frequency is determined by the absolute difference between the individual wave frequencies.
2
Subtract the lower frequency from the higher frequency to find the beat frequency
fbeat=445440=5 Hzf_{\text{beat}} = |445 - 440| = 5\text{ Hz}
The rate of periodic intensity variation (beat frequency) is governed by fbeat=f2f1f_{\text{beat}} = |f_2 - f_1|.

Anahtar Kavram

Beat Frequency and Wave Superposition
Soru 566Soru

A metal surface inside a vacuum cell is illuminated by incident photons each having an energy of 6.2 eV6.2\text{ eV}. If the maximum kinetic energy of the emitted photoelectrons is 2.4 eV2.4\text{ eV}, what is the work function of the metal in electron-volts (eV\text{eV})?

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Cevap: 3.8

Cevap

The work function of the metal is 3.8 eV3.8\text{ eV}.
According to Einstein's photoelectric equation, the total energy of an incident photon (E=6.2 eVE = 6.2\text{ eV}) equals the work function of the metal (W0W_0) plus the maximum kinetic energy of the ejected photoelectrons (Kmax=2.4 eVK_{\max} = 2.4\text{ eV}). Subtracting the kinetic energy from the photon energy gives W0=6.2 eV2.4 eV=3.8 eVW_0 = 6.2\text{ eV} - 2.4\text{ eV} = 3.8\text{ eV}.

Adım Adım Çözüm

1
State Einstein's photoelectric equation
E=W0+KmaxE = W_0 + K_{\max}
Relates the incident photon energy to the metal work function and photoelectron kinetic energy.
2
Rearrange the equation to solve for the work function
W0=EKmaxW_0 = E - K_{\max}
Isolates the work function W0W_0 on one side of the equation.
3
Substitute the given numerical values and compute
W0=6.2 eV2.4 eV=3.8 eVW_0 = 6.2\text{ eV} - 2.4\text{ eV} = 3.8\text{ eV}
Evaluates the difference to obtain the minimum energy needed to remove an electron.

Anahtar Kavram

Einstein's Photoelectric Equation and Work Function
Soru 567Soru

A beaker containing water of density 1000 kg/m31000\text{ kg/m}^3 rests on a digital weighing scale, giving an initial reading of 1.50 kg1.50\text{ kg}. A solid aluminum block of mass 0.80 kg0.80\text{ kg} and density 2500 kg/m32500\text{ kg/m}^3 is suspended from a string and completely immersed in the water without touching the bottom or sides of the beaker. What is the new reading on the digital weighing scale, in kilograms? (Take g=10 m/s2g = 10\text{ m/s}^2)

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Cevap: 1.82

Cevap

The new reading on the digital weighing scale is 1.82 kg1.82\text{ kg}.
When the aluminum block is fully submerged in the water, it displaces a volume of water equal to its own volume (V=0.802500=3.2×104 m3V = \frac{0.80}{2500} = 3.2 \times 10^{-4}\text{ m}^3). The mass of this displaced water is mwater=1000×3.2×104=0.32 kgm_{\text{water}} = 1000 \times 3.2 \times 10^{-4} = 0.32\text{ kg}. The upthrust exerted by the water upward on the block is equal to the weight of the displaced water (3.2 N3.2\text{ N}). By Newton's Third Law, the block exerts an equal and opposite downward reaction force (3.2 N3.2\text{ N}) on the water. This extra downward force adds an equivalent mass of 0.32 kg0.32\text{ kg} to the digital scale reading, making the new reading 1.50 kg+0.32 kg=1.82 kg1.50\text{ kg} + 0.32\text{ kg} = 1.82\text{ kg}.

Adım Adım Çözüm

1
Calculate the volume of the submerged block
Volume V=3.2×104 m3V = 3.2 \times 10^{-4}\text{ m}^3
The volume of fluid displaced by a completely submerged body equals the volume of the body itself.
2
Find the mass of the displaced water
Mass of displaced water mwater=0.32 kgm_{\text{water}} = 0.32\text{ kg}
According to Archimedes' principle, the upthrust equals the weight of the displaced fluid, which corresponds to a displaced mass of ρwaterV\rho_{\text{water}} V.
3
Apply Newton's Third Law to determine the change in scale reading
Scale reading increase Δm=0.32 kg\Delta m = 0.32\text{ kg}
The fluid exerts an upward buoyant force on the block, so by Newton's Third Law, the block exerts an equal downward reaction force on the fluid, transferring an effective weight equal to the upthrust onto the scale.
4
Compute the total new scale reading
New scale reading =1.82 kg= 1.82\text{ kg}
Sum the initial mass reading of the beaker system (1.50 kg1.50\text{ kg}) and the mass of the displaced water (0.32 kg0.32\text{ kg}).

Anahtar Kavram

Apparent weight transfer, Archimedes' principle, and Newton's Third Law
Soru 568Soru

A particle undergoing simple harmonic motion moves with an angular frequency of 4 rad/s4\text{ rad/s} and an amplitude of 0.5 m0.5\text{ m}. What is the maximum speed of the particle in m/s\text{m/s}?

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Cevap: 2

Cevap

The maximum speed of the particle is 2.0 m/s2.0\text{ m/s}.
The magnitude of velocity in simple harmonic motion varies with displacement xx according to v=ωA2x2v = \omega \sqrt{A^2 - x^2}. The speed reaches its maximum value when the particle passes through the equilibrium position (x=0x = 0), giving vmax=ωAv_{\text{max}} = \omega A. Substituting ω=4 rad/s\omega = 4\text{ rad/s} and A=0.5 mA = 0.5\text{ m} gives vmax=4×0.5=2.0 m/sv_{\text{max}} = 4 \times 0.5 = 2.0\text{ m/s}.

Adım Adım Çözüm

1
Identify the given physical parameters.
ω=4 rad/s\omega = 4\text{ rad/s} and A=0.5 mA = 0.5\text{ m}
These values define the speed profile of the simple harmonic oscillator.
2
Apply the SHM formula for maximum speed.
vmax=ωAv_{\text{max}} = \omega A
Peak speed occurs at the equilibrium position where displacement is zero.
3
Substitute the values to calculate the maximum speed.
vmax=4×0.5=2.0 m/sv_{\text{max}} = 4 \times 0.5 = 2.0\text{ m/s}
Multiplying angular frequency by amplitude yields the maximum linear velocity.

Anahtar Kavram

Maximum speed in Simple Harmonic Motion
Soru 569Soru

A diver is swimming at a depth of 3.5 m3.5\text{ m} below the surface of a freshwater lake. If the density of water is 1000 kg/m31000\text{ kg/m}^3 and the acceleration due to gravity g=10 m/s2g = 10\text{ m/s}^2, what is the gauge pressure exerted on the diver in pascals?

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Cevap: 35000

Cevap

35000 Pa
The gauge pressure exerted by a static column of fluid is given by P=hρgP = h \rho g. Using the values h=3.5 mh = 3.5\text{ m}, ρ=1000 kg/m3\rho = 1000\text{ kg/m}^3, and g=10 m/s2g = 10\text{ m/s}^2, the pressure is P=3.5×1000×10=35000 PaP = 3.5 \times 1000 \times 10 = 35000\text{ Pa}.

Adım Adım Çözüm

1
Identify the formula for liquid hydrostatic pressure
P=hρgP = h \rho g
Gauge pressure at a depth hh in a static fluid depends on depth, fluid density, and gravitational field strength.
2
Substitute the given numerical values
P=3.5×1000×10P = 3.5 \times 1000 \times 10
Substitute depth h=3.5 mh = 3.5\text{ m}, density ρ=1000 kg/m3\rho = 1000\text{ kg/m}^3, and g=10 m/s2g = 10\text{ m/s}^2.
3
Perform the multiplication to determine the pressure
35000 Pa35000\text{ Pa}
Complete the calculation to get the pressure in SI units (Pascals).

Anahtar Kavram

Hydrostatic Pressure in Static Fluids
Tahmini Süre:45s
Soru 570Soru

A capacitor of capacitance 50 μF50\ \mu\text{F} is connected across an alternating current (AC) source operating at a frequency of 100π Hz\frac{100}{\pi}\ \text{Hz}. What is the capacitive reactance of the capacitor?

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Cevap: 100

Cevap

The capacitive reactance of the capacitor is 100 Ω100\ \Omega.
Capacitive reactance XCX_C is given by the formula XC=12πfCX_C = \frac{1}{2\pi f C}. Substituting C=50×106 FC = 50 \times 10^{-6}\ \text{F} and f=100π Hzf = \frac{100}{\pi}\ \text{Hz} into the formula yields XC=12π(100/π)(50×106)=1102=100 ΩX_C = \frac{1}{2\pi (100/\pi) (50 \times 10^{-6})} = \frac{1}{10^{-2}} = 100\ \Omega.

Adım Adım Çözüm

1
Convert capacitance to farads and state all given values
C=50×106 FC = 50 \times 10^{-6}\ \text{F} and f=100π Hzf = \frac{100}{\pi}\ \text{Hz}
Calculations require standard SI base units.
2
Apply the formula for capacitive reactance
XC=12πfCX_C = \frac{1}{2\pi f C}
Capacitive reactance measures the opposition offered by a capacitor to alternating current.
3
Substitute the values and calculate the result
XC=12π100π(50×106)=110,000×106=100 ΩX_C = \frac{1}{2\pi \cdot \frac{100}{\pi} \cdot (50 \times 10^{-6})} = \frac{1}{10,000 \times 10^{-6}} = 100\ \Omega
The factor π\pi cancels out directly, making the arithmetic simple.

Anahtar Kavram

Capacitive Reactance in AC Circuits
Soru 571Soru

A solid uniform cylinder of height 0.20 m0.20\text{ m} and cross-sectional area 5.0×103 m25.0 \times 10^{-3}\text{ m}^2 floats vertically at the boundary between oil of density 800 kg/m3800\text{ kg/m}^3 and water of density 1000 kg/m31000\text{ kg/m}^3. If a height of 0.08 m0.08\text{ m} of the cylinder extends into the water layer while the remaining upper portion is completely covered by the oil layer, what is the mass of the cylinder in kilograms?

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Cevap: 0.88

Cevap

The mass of the cylinder is 0.88 kg0.88\text{ kg}.
According to the Law of Flotation, a floating body displaces its own weight of fluid. When floating at the interface of two immiscible liquids, the total mass of the body equals the sum of the masses of the displaced liquids. Displaced water mass is ρwAhw=0.40 kg\rho_w A h_w = 0.40\text{ kg} and displaced oil mass is ρoAho=0.48 kg\rho_o A h_o = 0.48\text{ kg}, giving a total cylinder mass of 0.88 kg0.88\text{ kg}.

Adım Adım Çözüm

1
Find the height of the cylinder submerged in the oil layer.
ho=0.20 m0.08 m=0.12 mh_o = 0.20\text{ m} - 0.08\text{ m} = 0.12\text{ m}
The total cylinder height is 0.20 m0.20\text{ m}, and 0.08 m0.08\text{ m} is submerged in water.
2
Calculate the volumes of water and oil displaced by the cylinder.
Vw=5.0×103×0.08=4.0×104 m3V_w = 5.0 \times 10^{-3} \times 0.08 = 4.0 \times 10^{-4}\text{ m}^3; Vo=5.0×103×0.12=6.0×104 m3V_o = 5.0 \times 10^{-3} \times 0.12 = 6.0 \times 10^{-4}\text{ m}^3
Volume displaced in each fluid equals cross-sectional area multiplied by the submerged height in that fluid.
3
Calculate the mass of the floating cylinder using the Law of Flotation.
m=ρwVw+ρoVo=(1000×4.0×104)+(800×6.0×104)=0.40 kg+0.48 kg=0.88 kgm = \rho_w V_w + \rho_o V_o = (1000 \times 4.0 \times 10^{-4}) + (800 \times 6.0 \times 10^{-4}) = 0.40\text{ kg} + 0.48\text{ kg} = 0.88\text{ kg}
For a floating object in static equilibrium, its mass equals the total mass of the fluids displaced by its submerged parts.

Anahtar Kavram

Law of Flotation in Layered Liquids
Tahmini Süre:1m 30s
Soru 572Soru

A tripositive ion, X3+X^{3+}, has a mass number of 5656 and contains 2323 electrons. How many neutrons are present in the nucleus of an atom of element XX?

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Cevap: 30

Cevap

30
To find the number of neutrons, first determine the atomic number (number of protons) of element XX. The ion X3+X^{3+} carries a +3+3 charge because it lost 3 electrons. Since X3+X^{3+} has 23 electrons, the neutral atom XX has 23+3=2623 + 3 = 26 electrons, which means it has 26 protons. The mass number (A=56A = 56) is the sum of protons (ZZ) and neutrons (NN). Thus, N=5626=30N = 56 - 26 = 30.

Adım Adım Çözüm

1
Determine the atomic number (number of protons) of element XX
Protons (ZZ) = 26
The tripositive ion X3+X^{3+} has lost 3 electrons. The neutral atom has 23+3=2623 + 3 = 26 electrons, which equals its proton count.
2
Calculate the number of neutrons
Neutrons (NN) = 30
Subtract the atomic number from the mass number: N=AZ=5626=30N = A - Z = 56 - 26 = 30.

Anahtar Kavram

Calculation of subatomic particles in ions using atomic number and mass number relationships
Soru 573Soru

The saturated vapour pressure of water at the dew point of a mass of air is 12 mmHg12\text{ mmHg}, while the saturated vapour pressure at the actual air temperature is 24 mmHg24\text{ mmHg}. Calculate the relative humidity of the air.

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Cevap: 50

Cevap

The relative humidity of the air is 50%.
Relative humidity is the ratio of the saturated vapour pressure at the dew point to the saturated vapour pressure at the actual air temperature, expressed as a percentage: (12 mmHg / 24 mmHg) * 100% = 50%.

Adım Adım Çözüm

1
Identify the saturated vapour pressure at the dew point and at the air temperature.
SVP at dew point = 12 mmHg; SVP at air temperature = 24 mmHg.
Relative humidity relies on the ratio of partial vapour pressure (SVP at dew point) to maximum vapour pressure at air temperature.
2
Apply the relative humidity formula.
Relative Humidity = (SVP at dew point / SVP at air temperature) * 100%
This formula defines the percentage saturation of the air.
3
Substitute the values and evaluate.
(12 / 24) * 100% = 50%
Dividing 12 by 24 gives 0.5, which equals 50% when multiplied by 100.

Anahtar Kavram

Relative Humidity Calculation
Tahmini Süre:45s
Soru 574Soru

An FM radio station transmits electromagnetic waves at a frequency of 1.0×108 Hz1.0 \times 10^8\text{ Hz} in a vacuum. Given that the speed of light in a vacuum is 3.0×108 m/s3.0 \times 10^8\text{ m/s}, what is the wavelength of these radio waves in meters?

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Cevap: 3

Cevap

The wavelength of the radio waves is 3.0 m3.0\text{ m}.
Applying the wave equation c=fλc = f\lambda, rearranging to λ=cf\lambda = \frac{c}{f}, and substituting c=3.0×108 m/sc = 3.0 \times 10^8\text{ m/s} and f=1.0×108 Hzf = 1.0 \times 10^8\text{ Hz} gives a wavelength of 3.0 m3.0\text{ m}.

Adım Adım Çözüm

1
Identify given parameters and key formula
Speed of light c=3.0×108 m/sc = 3.0 \times 10^8\text{ m/s}, frequency f=1.0×108 Hzf = 1.0 \times 10^8\text{ Hz}, wave equation c=fλc = f\lambda
The electromagnetic wave equation relates speed, frequency, and wavelength.
2
Rearrange for wavelength and substitute given values
\lambda = \frac{c}{f} = \frac{3.0 \times 10^8}{1.0 \times 10^8} = 3.0\text{ m}
Dividing the speed of propagation by the wave frequency yields the spatial wavelength.

Anahtar Kavram

Wave equation relating speed, frequency, and wavelength of electromagnetic waves
Soru 575Soru

The line y=2x1y = 2x - 1 intersects the curve y=x24x+4y = x^2 - 4x + 4 at two distinct points, (x1,y1)(x_1, y_1) and (x2,y2)(x_2, y_2). Calculate the sum of the yy-coordinates of these two points of intersection, y1+y2y_1 + y_2.

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Cevap: 10

Cevap

The sum of the yy-coordinates of the points of intersection is 10.
Equating y=2x1y = 2x - 1 and y=x24x+4y = x^2 - 4x + 4 yields x26x+5=0x^2 - 6x + 5 = 0, whose solutions are x=1x = 1 and x=5x = 5. Substituting these values into y=2x1y = 2x - 1 gives y1=1y_1 = 1 and y2=9y_2 = 9. The sum y1+y2=1+9=10y_1 + y_2 = 1 + 9 = 10.

Adım Adım Çözüm

1
Equate the linear and quadratic equations to eliminate yy.
x26x+5=0x^2 - 6x + 5 = 0
Setting 2x1=x24x+42x - 1 = x^2 - 4x + 4 allows finding the xx-coordinates of the intersection points.
2
Solve the quadratic equation for xx.
x1=1x_1 = 1 and x2=5x_2 = 5
Factoring (x1)(x5)=0(x - 1)(x - 5) = 0 yields the two xx-values.
3
Determine the corresponding yy-values using y=2x1y = 2x - 1.
y1=1y_1 = 1 and y2=9y_2 = 9
Substituting x=1x = 1 yields y=1y = 1, and substituting x=5x = 5 yields y=9y = 9.
4
Calculate the sum of the yy-coordinates.
10
Adding y1+y2=1+9=10y_1 + y_2 = 1 + 9 = 10.

Anahtar Kavram

Solving simultaneous linear and quadratic equations to find coordinates of intersection
Soru 576Soru

The 4th4^{\text{th}} term of an arithmetic progression (A.P.) is 1515 and the 9th9^{\text{th}} term is 3535. Calculate the sum of the first 1010 terms of the progression.

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Cevap: 210

Cevap

The sum of the first 10 terms of the progression is 210.
Using the nthn^{\text{th}} term formula Tn=a+(n1)dT_n = a + (n-1)d, the equations a+3d=15a + 3d = 15 and a+8d=35a + 8d = 35 yield common difference d=4d = 4 and first term a=3a = 3. Substituting these into the sum formula Sn=n2[2a+(n1)d]S_n = \frac{n}{2}[2a + (n-1)d] for n=10n = 10 yields S10=5[2(3)+9(4)]=210S_{10} = 5[2(3) + 9(4)] = 210.

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1
Set up equations for the given terms
a+3d=15a + 3d = 15 and a+8d=35a + 8d = 35
The nthn^{\text{th}} term of an A.P. is given by Tn=a+(n1)dT_n = a + (n-1)d.
2
Solve for the common difference dd
d=4d = 4
Subtracting (a+3d=15)(a + 3d = 15) from (a+8d=35)(a + 8d = 35) gives 5d=205d = 20, so d=4d = 4.
3
Solve for the first term aa
a=3a = 3
Substituting d=4d = 4 into a+3(4)=15a + 3(4) = 15 yields a=1512=3a = 15 - 12 = 3.
4
Calculate the sum of the first 10 terms
S10=210S_{10} = 210
Applying S10=102[2(3)+9(4)]=5(6+36)=210S_{10} = \frac{10}{2}[2(3) + 9(4)] = 5(6 + 36) = 210.

Anahtar Kavram

Finding terms and sums of an Arithmetic Progression using simultaneous linear equations
Tahmini Süre:1m 30s
Soru 577Soru

An alternating current (AC) series circuit contains a resistor, an inductor, and a capacitor. The root-mean-square (RMS) potential differences measured across the resistor, inductor, and capacitor are 80 V80\text{ V}, 110 V110\text{ V}, and 50 V50\text{ V}, respectively. What is the total supply voltage across the circuit in volts?

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Cevap: 100

Cevap

The total supply voltage across the series AC circuit is 100 V100\text{ V}.
In a series alternating current circuit, the voltages across the resistor, inductor, and capacitor are not in phase. The resistor voltage is in phase with the current, whereas inductor voltage leads by 9090^\circ and capacitor voltage lags by 9090^\circ. The total voltage is calculated using vector addition: V=VR2+(VLVC)2V = \sqrt{V_R^2 + (V_L - V_C)^2}. Substituting the given values gives V=802+(11050)2=802+602=6400+3600=100 VV = \sqrt{80^2 + (110 - 50)^2} = \sqrt{80^2 + 60^2} = \sqrt{6400 + 3600} = 100\text{ V}.

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1
Identify the RMS potential differences across each component.
VR=80 VV_R = 80\text{ V}, VL=110 VV_L = 110\text{ V}, and VC=50 VV_C = 50\text{ V}.
In a series AC circuit, voltages across reactive components are out of phase with the resistor voltage.
2
Calculate the net reactive voltage difference between the inductor and capacitor.
VLVC=110 V50 V=60 VV_L - V_C = 110\text{ V} - 50\text{ V} = 60\text{ V}.
Inductive voltage leads current by 9090^\circ while capacitive voltage lags current by 9090^\circ, making them 180180^\circ out of phase with each other.
3
Determine total supply voltage using vector (phasor) addition.
V=VR2+(VLVC)2=802+602=6400+3600=10000=100 VV = \sqrt{V_R^2 + (V_L - V_C)^2} = \sqrt{80^2 + 60^2} = \sqrt{6400 + 3600} = \sqrt{10000} = 100\text{ V}.
The resistive voltage and net reactive voltage are perpendicular (9090^\circ phase angle difference).

Anahtar Kavram

Phasor Addition of Voltages in a Series AC Circuit
Soru 578Soru

Evaluate the definite integral 13(4x36x)dx\int_{1}^{3} (4x^3 - 6x) \, dx.

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Cevap: 56

Cevap

The value of the definite integral is 56.
To evaluate the definite integral 13(4x36x)dx\int_{1}^{3} (4x^3 - 6x) \, dx, integrate the function term-by-term to obtain F(x)=x43x2F(x) = x^4 - 3x^2. Evaluating F(x)F(x) at the upper bound x=3x = 3 yields 5454, and evaluating at the lower bound x=1x = 1 yields 2-2. Subtracting the lower bound value from the upper bound value gives 54(2)=5654 - (-2) = 56.

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1
Find the indefinite integral of the function
\int (4x^3 - 6x) \, dx = x^4 - 3x^2
Apply the power rule of integration \int x^n \, dx = \frac{x^{n+1}}{n+1}
2
Substitute the upper limit x = 3 into the antiderivative F(x)
F(3) = 3^4 - 3(3)^2 = 81 - 27 = 54
Evaluate F(b) for b = 3
3
Substitute the lower limit x = 1 into the antiderivative F(x)
F(1) = 1^4 - 3(1)^2 = 1 - 3 = -2
Evaluate F(a) for a = 1
4
Subtract F(a) from F(b)
54 - (-2) = 56
Apply the Fundamental Theorem of Calculus: \int_{a}^{b} f(x) \, dx = F(b) - F(a)

Anahtar Kavram

Definite Integration using the Fundamental Theorem of Calculus
Soru 579Soru

A monochromatic beam of light with a wavelength of 600 nm600\text{ nm} in air enters a glass block of refractive index 1.501.50. What is the wavelength of the light inside the glass block in nanometers (nm\text{nm})?

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Cevap: 400

Cevap

The wavelength of the light inside the glass block is 400 nm400\text{ nm}.
The speed and wavelength of light both decrease by a factor of the refractive index nn when entering a medium from air, while the frequency stays constant (v=fλv = f\lambda). Thus, λ=λ0n=6001.50=400 nm\lambda = \frac{\lambda_0}{n} = \frac{600}{1.50} = 400\text{ nm}.

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1
Identify the relevant formula connecting refractive index and wavelength
λ=λ0n\lambda = \frac{\lambda_0}{n}
When light passes from air into a medium, its frequency remains unchanged while its speed and wavelength decrease proportionally by a factor of the refractive index nn.
2
Substitute the given values into the equation
λ=600 nm1.50\lambda = \frac{600\text{ nm}}{1.50}
The wavelength in air is 600 nm600\text{ nm} and the refractive index of glass is 1.501.50.
3
Perform the calculation
λ=400 nm\lambda = 400\text{ nm}
Dividing 600600 by 1.501.50 yields 400400.

Anahtar Kavram

Refraction and Wavelength Change in a Medium
Soru 580Soru

Find the yy-intercept of the tangent line to the curve y=x36x+8y = x^3 - 6x + 8 at the point where x=1x = 1.

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Cevap: 6

Cevap

The yy-intercept of the tangent line is 6.
Differentiating y=x36x+8y = x^3 - 6x + 8 yields dydx=3x26\frac{dy}{dx} = 3x^2 - 6. At x=1x = 1, the point on the curve is (1,3)(1, 3) and the gradient of the tangent is m=3m = -3. Substituting into the point-slope form y3=3(x1)y - 3 = -3(x - 1) gives y=3x+6y = -3x + 6. Setting x=0x = 0 identifies the yy-intercept as 6.

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1
Find the point of tangency on the curve
For x=1x = 1, y=(1)36(1)+8=3y = (1)^3 - 6(1) + 8 = 3. The point is (1,3)(1, 3).
The tangent line touches the curve at the point corresponding to x=1x = 1.
2
Find the gradient function of the curve
dydx=3x26\frac{dy}{dx} = 3x^2 - 6
The derivative of the curve equation gives the gradient of the tangent at any point.
3
Calculate the gradient of the tangent line at x=1x = 1
m = 3(1)^2 - 6 = -3
Substitute x=1x = 1 into the derivative.
4
Formulate the equation of the tangent line
y - 3 = -3(x - 1) \implies y = -3x + 6
Apply the point-slope line equation yy1=m(xx1)y - y_1 = m(x - x_1) using (1,3)(1, 3) and m=3m = -3.
5
Determine the yy-intercept
Setting x=0x = 0 yields y=6y = 6.
The yy-intercept is the value of yy when x=0x = 0.

Anahtar Kavram

Tangents to Curves and Axis Intercepts
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