Electrical Units and Concepts Quiz

The SI Unit of potential difference is:

• Ohm

• EMF

• Volt

• Joule

The SI Unit of power is:

• Energy

• Watt

• Joule

• Kilo-watt

The SI Unit of current is:

• Joule

• Watt

• Ampere

• Ohm

A fuse in an electrical circuit is used to:

• Limit the applied voltage to the load

• Open the circuit in the event of excess current flow

• Prevent short circuits from happening

• Control the amount of energy being dissipated.

The Joule is a measure of:

• Current flow in a circuit

• Rate of doing work

• Energy transferred

• Force acting on a body.

The rate at which energy is consumed is calculated using the formula:

• P=IR

Wire suitable for the heating element in an electrical appliance would normally possess:

• Low resistance

• Large cross-sectional area

• High resistivity

• High current density

Which statement best describes a car battery:

• A rechargeable cell

• A number of cells connected in series

• A special battery used in vehicles only

• A secondary cell

Which statement BEST describes a Primary Cell:

• Can be charged many times

• Converts electrical to chemical energy

• Cannot be recharged

• Has low internal resistance.

What is the power dissipated by a 15 Ohm resistor when drawing a current of 0.8 Amps?

• 180 W

• 9.6 W

• 12 W

• 18.75 W