1. A parallel-plate capacitor has capacitance C. A second
parallel-plate capacitor has plates with twice the area and
half the separation. The capacitance of this second
capacitor is most nearly
A)
1
4C
B)
1
2C
4. The product of 2 ohms 2 farads is equal t
1. A long, straight wire has an internal resistance of 5 /m. If
it is moved at a velocity of 3 m/s in a magnetic field of 4 T,
what is the current induced in the wire?
A) 0 A
3. A circular loop of wire with resistance R and radius a is
oriented with its p
Review for the first exam, 2426, Chpt. 21 24. Lianxi Ma
First part: Conceptual questions.
1.
(A) When the distance between the two charges is doubled, the force between them is
(Use Coulombs law; r is doubled, then r2 is increase by a factor of 4)
A)
redu
1 996-3 HUI - 3
3. In the leCllll shown above. X. 1’, and Z represent three light bulbs. leech rated It HI watts. III! volts. Assume
that the minim: of the bulbs are constant and do not depend on the current.
ta} Whit is the resistenee of each bulb?
(b)