RC circuits

Immediately after the switch is closed, the voltage across the 3uF capacitor is

• 0 V
• 45 V
• 22.5 V
• 45e^-t/RC V

Immediately after the switch closes, the current in the circuit is

• 0 A
• 45 microAmps
• 22.5 microAmps
• 45e^-t/RC microAmps

The time constant for this circuit is

• 0
• 3 seconds
• 3 microseconds
• 0.33 seconds

After the switch is closed, the voltage across the capacitor is

• 45(1 - e^-t/RC)
• 45(e^-t/RC)

After the switch is closed, the current is 

• 0.000045(1-e^-t/RC)
• 0.000045e^-t/RC

When the capacitor is fully charged, the voltage across the capacitor is _________ and the current in the circuit is _________.

• 45 V, 0 A
• 0 V, 45 microA
• 22.5 V, 45 micro A
• 3 microV, 0 A

If there are 6 batteries in the circuit shown, how many volts are in the circuit?

• 1.5
• 6
• 9
• 54

What is the voltage at each branch in the circuit below?

• 2
• 4
• 6
• 18

A motor has a current of 2.00 A flowing through it when it is powered with a
12-volt battery.  What is the power used by the motor? 

• 16
• 6
• 14
• 24

Calculate the current for a 120-volt refrigerator that uses 650 watts of power.

• 0.18
• 5.4
• 120
• 78,000