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Which of the following is a unit of power?
Joule
Watt-second
Newton
Watt
Watt
Power is defined as the rate at which work is performed or energy is transferred ┬╖ Its SI unit is the Watt (W), named after James Watt, which is equivalent to one joule per second.
Power is defined as the rate at which work is performed or energy is transferred ┬╖ Its SI unit is the Watt (W), named after James Watt, which is equivalent to one joule per second.
If work is the total amount of bricks carried to the top of a building, power is how fast you carry them; a crane has higher power than a person because it moves more bricks in the same amount of time.
WET: Work = Energy, Time involved in Power.
P=tWтАЛ тАФ Power equals Work divided by time
P=I2R тАФ Electrical power dissipation in a resistor
P=FтЛЕv тАФ Instantaneous mechanical power
Power measures the time derivative of energy consumption ┬╖ When a system performs 1 Joule of work in 1 second, the power dissipated is 1 Watt ┬╖ Mathematically, it relates force, displacement, and time through the relationship P=tWтАЛ=FтЛЕv, where F is force and v is velocity.
Power is a scalar quantity.
The SI unit of power is Watt (W) = JтЛЕsтИТ1.
Horsepower (hp) is a common non-SI unit where 1┬аhpтЙИ746┬аW.
Provides a standard measure for engine and appliance performance.
Does not indicate the total energy capacity of a system, only the rate of usage.
Rating electrical appliances like light bulbs and heaters.
Measuring the output of mechanical engines and motors.
Joule (Option A) is the unit of Energy.
Watt-second (Option B) is another unit of Energy (1┬аWs=1┬аJoule).
Newton (Option C) is the SI unit of Force.
D is correct тАФ Watt is the standard SI derived unit for measuring power.
Always distinguish between energy units (Joule, kWh, Calorie) and power units (Watt, Horsepower) to avoid common trap questions in Physics.