The loaded cab of an elevator has a mass of 3.6 × 103 kg and moves 216 m up the shaft in 17 s at constant speed. At what average rate does the force from the cable do work on the cab?
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What range of velocities might an electron have if it is confined to a 0.4-nm-wide region? And if it is confined to about the size of an atom (0.1-nm-wide region)? Compare this to your previous knowledge about the speed of electrons in the atom. What does this mean?
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A 10 cm long thin glass rod uniformly charged to +10 nC and a 10 cm long thin plastic rod uniformly charged to -10nC are placed side by side 4 cm apart.
a. Find the electric field at distances 1.0 cm, 2.0 cm and 3.0 cm from the glass rod along the line connecting the midpoints of the two rods. (Hint: treat the rods as a uniform line of charges.)
b. If the plastic rod is exchanged for a glass rod of the same size uniformly charged to +10 nC, what is the new electric field at 1.0 cm, 2.0 cm and 3.0 cm?
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Blue light of wavelength 470 nm passes through an interference grating with a slit spacing of0.001 mm and makes an interference pattern on the wall.
How many bright fringes will be seen?
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A solid cylinder with a mass of 3 kg, a radius of 25 cm, and a length of 40 cm is rolling across a horizontal floor with a linear speed of 12 m/s. The cylinder then comes to a ramp, and, as it is rolling up this ramp without slipping, it is slowing down. When the cylinder finally comes to a stop and begins rolling back down the ramp, how high is it above the floor?
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1. How can contrast be achieved in a display using texture? Color? Line? Give an example of each
2. Describe the concept of proportion, and explain why it is important to any visual presentation
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A meteor with a mass of 1 kg moving at 20 km/s collides with Jupiter's atmosphere. The meteor penetrates 100 km into the atmosphere and disintegrates. What is the average force on the meteor once it enters Jupiter's atmosphere (Ignore gravity).
*The answer is 2 x 10^3 N but I have no idea why.
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What is the escape speed on a spherical asteroid whose radius is 700 km and whose gravitational acceleration at the surface is 0.685 m/s2? (b) How far from the surface will a particle go if it leaves the asteroid's surface with a radial speed of 694 m/s? (c) With what speed will an object hit the asteroid if it is dropped from 1066 km above the surface? (SHOW ALL WORK)
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Q.6 (same as problem 3) The phenomenon that distinguishes transverse waves from longitudinal waves is
A. Frequency
B. Amplitude
C. Polarization
D. Speed
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Two very long solenoids have the same number of turns per unit length, and carry the same current, but the radius of the cross-section of solenoid #1 is twice that of solenoid #2. How do the magnetic field fluxes through the solenoids compare?
Select the best answer.
Select the best answer.
The flux through solenoid #2 is twice the flux through solenoid #1. |
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They are equal. |
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The flux through solenoid #1 is twice the flux through solenoid #2. |
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The flux through solenoid #1 is four times the flux through solenoid #2 |
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Problem 9.41
A firecracker in a coconut blows the coconut into three pieces. Two pieces of equal mass fly off south and west, perpendicular to each other, at 20 m/s . The third piece has twice the mass as the other two.
Part A
What is the speed of the third piece?
Express your answer using two significant figures.
Part B
What is the direction of the third piece? Give the direction as an angle east of north.
Express your answer using two significant figures.
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A point of charge q is placed at the point (-d,0) and a second point charge of charge 2q is placed at point (2d,0). a) What is the force on the third charge of charge -q placed at point (0,d) if d=190nm and q=250nC? b) find the two positive charges placed on the x-axis? c) What is the electric field at the origin?
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Two objects with masses m1 = 37 kg and m2 = 39 kg are moving toward each other with speeds V1 = 14 m/s and V2 = 18 m/s. They collide and stick together. Find their final: speed:
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Kinetic energy is conserved in an elastic collision by definition. Show, using the Galilean transformation equations, that if a collision is elastic in one inertial frame it should be elastic in all inertial frames
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Arrange four quarter coins touching each other as a 2-D square lattice. Calculate the area of the air-space (dead-space). (Ignore the thickness of the quarters.) Repeat the problem for a triangular lattice.
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