Question

Rate at which electric work is done is called as ?
A) Electric power
B) Electric energy
C) Electric force
D) Voltage

Answer 1

Hint:Power is defined as the rate of doing any work or energy liberated or consumed of any electrical appliance is the power rating of that appliance . The SI unit of power is joule per second( joule / sec ).

Step by step solution :-
Option (A)
Electrical power is the rate , per unit time, at which electrical energy is transferred by an electrical circuit.
The S.I unit of electric power is watt i.e
The power 1 watt means one joule of energy per sec.
The power 100 watt means 100 joule of energy per sec.
Electrical power is usually produced by electric generators , but this can also be supplied by sources such as electric batteries.
Hence option (A) is the correct answer.

Option (B)
Electric energy :- Electric energy is the energy derived from electric potential energy , in general it is the energy that has been converted from electric potential energy. Electric energy is supplied by the combination of electric current and electric potential that is delivered by an electrical circuit.
Once converted from potential energy ,electrical energy can be called another type of energy ( heat , light, mechanical etc.)

Option ( C )
Electric force :- An electric force is exerted between any two charged objects. Objects with the same charge that mean like charges repel each and objects with the opposite charge that means unlike charges attract each other.
One positive charge will attract with a negative charge and will repel with another positive charge.

Option (D)
Voltage :- Voltage is the pressure from an electrical circuit;s power source that pushes charged electrons ( i.e current ) through a conducting loop , enables them to do some work such as heating , lighting etc.

Note:-The electric power for a D-C ( Direct – Current ) circuit is given by the product of the current \[I\]passing through a system and the potential difference( \[V\]) across it.
\[{P_{D - C}} = I.V\]
The electric power for an A-C ( Alternating – Current ) circuit is given by the product of the current \[I\]passing through a system and potential difference ( \[V\]) across its times the power factor of the circuit.
\[{P_{A - C}} = IV\cos \varphi \]
\[\cos \varphi \] is called the power factor of the circuit.