Consider two copper wires. One has twice the length and twice the cross-sectional area of the other. How do the resistances of these two wires compare?
A)
Both wires have the same resistance.
B)
The longer wire has four times the resistance of the shorter wire.
C)
The longer wire has twice the resistance of the shorter wire.
D)
The longer wire has eight times the resistance of the shorter wire.
E)
none of the given answers
A
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The planet COROT-14b is only slightly larger than Jupiter, but is several times as massive. Which is the most plausible explanation for its similar size to Jupiter?
A) The mass measurement is mistaken, and it is actually about 10 times more massive than Jupiter. B) Planets that are close to a star are hotter, causing them to puff up. C) It is made of elements other than hydrogen and helium which do not compress under their own gravity. D) The hydrogen and helium gas compressed under their own gravity to a higher density than Jupiter.
In the context of Einstein's general theory of relativity, briefly explain Schwarzschild black holes
What will be an ideal response?
Equilibrium: Two blocks, A and B, are being pulled to the right along a horizontal surface by a horizontal 100-N pull, as shown in the figure. Both of them are moving together at a constant velocity of 2.0 m/s to the right, and both weigh the same. 
Which of the figures below shows a correct free-body diagram of the horizontal forces acting on the upper block, A?
A. 
B. 
C. 
D. 
E. 
Uniform Circular Motion: When a car goes around a circular curve on a horizontal road at constant speed, what force causes it to follow the circular path?
A. the normal force from the road B. the friction force from the road C. gravity D. No force causes the car to do this because the car is traveling at constant speed and therefore has no acceleration.