Power

Question 1

A 10 V battery supplies a resistive load of 10 ohms for 1 minute. What is the power supplied?

Answer 1

10 W

Question 2

A resistor dissipates 80 Watts. If it runs for 4 hours 15 minutes, how much energy is dissipated in total?

Answer 2

1.224 MJ

Question 3

The earth lead of a 24 V equipment is 0.5 ohm resistance and carries 80 A. How much power does it dissipate?

Answer 3

3.2 kW

Question 4

What is the power dissipated in a 500 ohm resistor with a 3A flow?

Answer 4

4.5 kW

Question 5

A DC circuit containing a total resistance of 100 ohms has a current flow of 250 mA. The power dissipated in the circuit is.

Answer 5

6.25 watts

Question 6

Power is the rate of doing work. It is measured in.

Answer 6

joules/second

Question 7

The power in a circuit when voltage and resistance is given can be found by.

Answer 7

V*V / R

Question 8

A 500 ohm resistor carries a 3 amp current. What is the power dissipated?

Answer 8

4.5 kW

Question 9

A 3 ohm resistor dissipates 27 Watts. How much current flows through it?

Answer 9

3 A

Question 10

A 48-volt source is required to furnish 192 watts to a parallel circuit consisting of three resistors of equal value. What is the value of each resistor?

Answer 10

36 ohm

Question 11

A piece of equipment is rated at 750 watts and the applied voltage is 30 volts. The value of the protection fuse should be.

Answer 11

30 amps

Question 12

How much power must a 24-volt generator furnish to a system which contains the following series loads? 5 ohm, 3 ohm and 12 ohm.

Answer 12

28.8 watts

Question 13

A direct current of 12 milliamperes flows through a circuit which has a resistance of 1000 ohms. The power dissipated by the circuit is.

Answer 13

144 milliwatts

Question 14

In a power circuit, the purpose of an inductor is.

Answer 14

to dampen power surges

Question 15

In the circuit shown, the power developed across the 10 kilo ohm resistor is.

Answer 15

250 mW

Question 16

A single phase circuit has an input voltage of 100V. The current is 10A and the circuit has a power factor of 0.5. The true power is.

Answer 16

500W

Question 17

Power in a DC circuit is found by.

Answer 17

multiplying the resistance by the current squared

Question 18

If the energy supplied to a circuit for 4hrs 15 minutes at 800 j/sec what would be the energy consumed?

Answer 18

3.4 KW Hrs

Question 19

A heater which consumes 800 Kilojoules/sec is on for 4hrs 15min. The energy consumed is.

Answer 19

3400 kWh

Question 20

A voltage of 250V causes a current of 30mA. What is the wattage?

Answer 20

7.5W

Question 21

Which requires the most electrical power during operation?

Answer 21

Two lights requiring 3 amperes each in a 24volt parallel system

Question 22

The power dissipated in a circuit with a known potential difference and resistance is calculated by.

Answer 22

finding the current and multiplying the answer by the resistance. OR dividing the square of the potential difference by the resistance.

Question 23

The power expended in a given circuit is.

Answer 23

proportional to the square of the voltage