Subtopic 5.2 Heating effects of electric current

The work done in moving the charge Q through a potential difference V

• Q/V

• V/Q

• QV

• 1/QV

If resistance increases in the circuit then the heat energy ______________

• increases

• decreases

• no change

• all the above

How much current is produced in an electric iron consumes energy at a rate of 880 W with the voltage is 220 V ?

• 2 ampere

• 4 ampere

• 6 ampere

• 8 ampere

An electric iron of resistance 10 Ω takes a current of 2 A. Calculate the heat developed in 3 Sec.

• 60 J

• 30 J

• 3.3 J

• 120 J

The electric heating is used in

• Fuse

• Light

• heater

• All of the above

The rate at which electric energy is dissipated or consumed in an electric circuit is caleed

• Electric Potential

• Electric Resistance

• Electric Power

• Electric Energy

The commercial unit of electric energy is

• Kilowatt hour

• Watt

• Joule

• Kilowatt

An electric bulb is connected to a 220 V generator. The current is 2 A. What is the power of the bulb?

• 110 watt

• 220 watt

• 440 watt

• 330 watt

An electric heater of resistance 8 Ω draws 15 A from the service mains 2 hours. Calculate the rate at which heat is developed in the heater

• 1800 watt

• 1800 joule

• 3600 joule

• 3600 watt

The picture shows an electrical circuit. This circuit is a series circuit because:

• It has 3 light bulbs.

• The same current flows through all three light bulbs.

• It uses a single battery.

• The electrical current has more than one path to flow through