PHYS 255 Lecture 8: P255_L7_flat

Multiple choice:

An LC circuit has an inductance of 20mH and a capacitance of 5.0µF. At time t = 0 the
charge on the capacitor is 3.0 µC and the current is 7.0mA. Thetotal energy is:
A. 4.1 × 10^-7 J
B. 4.9 × 10^-7 J
C. 9.0 × 10^-7 J
D. 1.4 × 10^-6 J
E. 2.8 × 10^-6 J

4. A step-down transformer that converts 120V ac to 10.0V AC (rmsvalues), and the secondary winding is connected to a purelyresistive circuit having an equivalent resistance of 2.00O.[20pts]
a. What is the output rms current to the circuit?
b. What is the input rms current to the primary coil?


ch 33 from Physics For Scientists And Engineers with Modern Physics(8th) by Raymond A. Serway