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8 Cards in this Set
- Front
- Back
- 3rd side (hint)
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24.8
Obtain the wavelength in vacuum for violet light whose frequency is 7.81 x 1014 Hz. Express your answer in nanometer (1 nm = 10−9 m). Do not enter unit. |
3.84×10^2 nm
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c=f(lambda)
c is speed of light=3.00E8 m/s |
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24.18
A communications satellite is in a synchronous orbit that is 3.47E+7 m directly above the equator. The satellite is located midway between Quito, Equador, and Belem, Brazil, two cities almost on the equator that are separated by a distance of 3.21E+6 m. Calculate the time it takes for a telephone call to go by way of satellite between these cities. Ignore the curvature of the earth. |
.23 s
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The satellite makes an isoscles triangle with the two cities as bases. 1.distance_between cities/2=a
2.vertical distance to satellite=b 3.do pythag to find c 4.2c=distance wave travels 5.time=distance/speed of light |
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24.21
A laser emits a narrow beam of light. The radius of the beam is 1.39E-3 m, and the power is 1.48E-3 W. What is the intensity of the laser beam? 2.44×102 W/m^2 |
2.44×102 W/m^2
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S is measured in m^2.
In this situation, s=P/A. r is given. pir^2=A. P/A=w/m^2 |
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24.25
The average intensity of sunlight at the top of the earth's atmosphere is 1384 W/m2. What is the maximum energy that a 22.5 m x 43.8 m solar panel could collect in one hour in this sunlight? |
4.91E9 J
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1.Find area=l*w
2.Intensity * area=W (cancel m^2) 3.Because W=J/s, and you need joules, do (answer to 2) * 3600 s=4.91E9 Joules (amount of power in one hour) |
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24.27
An argon-ion laser produces a cylindrical beam of light whose average power is 0.795 W. How much energy is contained in a 2.50 m length of the beam? |
6.62×10-9 J
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1.find amount of time it takes laser to travel distance given
t=d/c (speed of light) 2.multiply (answer to 1) * given power=answer |
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24.32
A speeder is pulling directly away and increasing his distance from a police car that is moving at 26.9 m/s with respect to the ground. The radar gun in the police car emits an electromagnetic wave with a frequency of 7.04E+9 Hz. The wave reflects from the speeder's car and returns to the police car, where its frequency is measured to be 333 Hz less than the emitted frequency. Calculate the speeder's speed with respect to the ground. |
34 m/s
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1.use (difference in f)=(f_s(vrel/c))*2
2.solve for v_rel 3.add v_rel to cop's speed (I always get 7.09E18 m/s for V_rel, but if I just take off the E18 and only add 7.09 m/s to the cop's speed it's the right one) |
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24.42
The maximum strength of the magnetic field in an electromagnetic wave is 3.46E-6 T. What is the maximum strength of the wave's electric field? |
1.04E3 N/C
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E=cB
given B, c is speed of L, multiply for E |
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24.43
An AM station is broadcasting a radio wave whose frequency is 1363 kHz. The value of the capacitance in the drawing below is 8.84E-11 F. What must be the value of the inductance in order that this station can be tuned in by the radio? |
1.54×10-4 H
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1.f_o=1/(2pi)(sqrrt(LC))
2.L=1/(4pi^2)(f_o)(C) |
