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1. Two 2.0 g spheres are charged equally and placed 2.0 cm apart. When
released, they begin to accelerate at 215 m/s2. What is the magnitude of the
charge on each sphere? (Give your answer in C)
2. An electron is launched at a 45° angle and a speed of 5.3 106 m/s from the
positive plate of the parallel-plate capacitor shown in Figure. The electron lands d
= 3.4 cm away.
(a) What is the electric field strength inside the capacitor? (Give your answer in
N/C)
(b) What is the minimum spacing between the plates? (Give your answer in cm)
3. A spherically symmetric charge distribution produces the electric field =
(4000r2) N/C where r is in m.
(a) What is the electric field strength at r = 15 cm? (Give your answer in N/C)
(b) What is the electric flux through a 30 cm diameter spherical surface that is
concentric with the charge distribution? (Give your answer in Nm2/C)
(c) How much charge is inside this 30 cm diameter spherical surface? (Give your
answer in C)
4. The same material is used to construct the two wires in Figure, in which vd =
2.5 10-4 m/s.
(a) What is the current in the 2.0 mm diameter segment of the wire? (Give your
answer in A)
(b) What is the electron drift speed in the 2.0 mm diameter segment of the wire?
(Give your answer in m/s)
5. What is the escape speed of an electron launched from the surface of a 1.2
cm diameter plastic sphere that has been charged to +7 nC? in the 2.0 mm
diameter segment of the wire? (Give your answer in m/s)
6. Metal sphere 1 has a positive charge of 5.0 nC. Metal sphere 2, which is one
third the diameter of sphere 1, is initially uncharged. The spheres are then
connected together by a long, thin metal wire.
(a) What is the final charge on sphere 1? (Give your answer in C)
(b) What is the final charge on sphere 2? (Give your answer in C)
7. A battery with an emf of 55 V is connected to the two capacitors shown in
Figure. Afterward, the charge on capacitor 2 is 427 µC. What is the capacitance
of capacitor 2? (Give your answer in μF)
8. Consider the circuit in Figure, in which V = 80 V and R = 6 .
(a) What is the current through the 2 resistor? (Give your answer in A)
(b) What is the the power dissipated by the 20 resistor? (Give your answer in
W)
(c) What is the potential at point a? (Give your answer in V)
9. The two springs in Figure each have a spring constant of 9 N/m. They are
stretched by 1.2 cm when a current passes through the wire. How big is the
current? (Give your answer in A)
10. Consider the circuit in Figure, in which C = 1.7 µF and L = 59 mH. The switch
has been in position 1 for a long time, and it is changed to position 2 at t = 0 s.
(a) What is the maximum current through the inductor? (Give your answer in mA)
(b) What is the first time at which the current is maximum? (Give your answer in
ms)