Resistance and Resistivity: Consider two copper wires of equal cross-sectional area. One wire has 3 times the length of the other. How do the resistances of these two wires compare?
A. Both wires have the same resistance.
B. The longer wire has 1/3 the resistance of the shorter wire.
C. The longer wire has 3 times the resistance of the shorter wire.
D. The longer wire has 9 times times the resistance of the shorter wire.
E. The longer wire has 27 times times the resistance of the shorter wire.
Answer: C
You might also like to view...
An object can remain balanced if
A. Its mass is equally distributed B. Its center of gravity is to the right of the pivot points C. Its center of gravity is to the left of the pivot point D. Its center of gravity is over the pivot point
Magnetic field lines come out of the south pole of a magnet and enter at the north pole
Indicate whether the statement is true or false
Harlow Shapley concluded that the Sun was not located at the center of the Milky Way Galaxy by
A) mapping the distribution of stars in the galaxy. B) mapping the distribution of gas clouds in the spiral arms. C) mapping the distribution of globular clusters in the galaxy. D) looking at the shape of the "milky band" across the sky. E) looking at other nearby spiral galaxies.
A metal blade (length = 80 cm) spins at a constant rate of 10 radians/s about a pivot at one end. A uniform magnetic field of 2.0 mT is directed at an angle of 30° with the plane of the rotation. What is the magnitude of the potential difference between the two ends of the blade?
a. 5.5 mV b. 6.4 mV c. 3.2 mV d. 11 mV e. 13 mV