G9PHY -Weekly Test 2

What is the unit of electrical energy?

• watt

• kWh

• meter

• seconds

What is the formula for Heat produced by current?

• a.    I = V/R

•      Q =I^2 Rt

• P = VI

• None of these

How much current is produced in an electric iron that has a power rating of 880 W when the voltage is 220 V?

• 2 ampere

• 6 ampere

• 8 ampere

• 4 ampere

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

• 60 J

• 3.3 J

• 120 J

• 30 J

When current flows through a resistor, some of the electrical energy delivered to the resistor is converted into heat energy and is dissipated. This heating effect is called:

• Ohm’s Law

• The heating effect of the current

• Electrical Power

• Electrical work

Heat developed in an electrical circuit due to the flow of current varies directly as:

• The time of the flow

• The square of the current

• The resistance of the circuit

• All of these

                                is electronic equipment that is used for the protection of electric circuits from short circuits or overcurrent.

• Ammeter

• Circuit Breaker

• Energy Meter

• None of these

What is the formula of electrical work?

• W = VIT

• W= VI

• P = VI

• W = VIt

What is the unit of heat?

• Seconds

• Joules

• Meters

• Watts

1.     1kWh =                          

• 3 600 000 Joules

• 3.6 Joules

•    36 Joules

• 3600 Joules