Week 6 Quiz in EE 200

Calculate the energy stored in a 22 µF capacitor when it is charged to 120 V?

• 290 mJ

• 317 mJ

• 158 mJ

• 3.17 mJ

Two series capacitors (one is 2 µF, the other of unknown value) are charged from a 24 V source. The 2-µF capacitor is charged to 16 V and the other to 8 V. The value of the unknown capacitor is _____.

• 1 µF

• 4 µF

• 2 µF

• 8 µF

An inductor, a 1-kΩ resistor, and a switch are connected in series across a 6 V battery. At the instant the switch is closed, the inductor voltage is

• 0 V

• 6 V

• 4 V

• 12 v

A 220- Ω resistor is in series with a 2.2-µF capacitor. The time constant is __________.

• 48 µs

• 2.42 µs

• 484 µs

• 24 µs

The winding resistance of a coil can be increased by

• using a thinner wire .

• increasing the number of turns

• changing the core material.

• increasing the number of turns or using thinner wire.

The current through a 120 mH coil is changing at a rate of 150 mA/s. The voltage induced across the coil is_____.

• 1.8 mV

• 180 mV

• 18 mV

• 1.25 V

An 18 V power supply is connected across a coil with a winding resistance of 180 Ω. Current flow in the coil is ________.

• 1 mA

• 100 mA

• 10 mA

• 1 A

A switch, a 220-Ω resistor, and a 60 mH inductor are in series across a 20 V battery. What is the current through the inductor two time constants after the switch is closed?

• 91 mA

• 57 mA

• 79 mA

• 400 mA

A 320 𝜇H coil is in series with a 3.3 k-Ω resistor. How long does it take for current to build up to its full value?

• 0.4848 s

• 0.4848 𝜇s

• 0.4848 ms

• 4.848 𝜇s

Five inductors are connected in series. The lowest value is 8 μH. If the value of each inductor is twice that of the preceding one, and if the inductors are connected in order of ascending values, the total inductance is _______.

• 8 H

• 64 μH

• 32 μH

• 248 μH