Test: Work, Force And Energy - 2 - Class 4 MCQ

The SI unit of power, the watt (W), is named after James Watt, a Scottish engineer and inventor who made significant contributions to the development of the steam engine.

Power is defined as the rate at which work is done. It quantifies how quickly or efficiently work is performed.

Power is calculated by dividing the work done by the time taken. In this case, the work done is 500 joules, and the time taken is 10 seconds. Therefore, the power output of the machine is 500 J / 10 s = 50 watts.

To convert horsepower to watts, we can use the conversion factor: 1 horsepower = 745.7 watts. Therefore, 150 horsepower is equal to 150 × 745.7 = 111,855 watts.

A stretched spring possesses potential energy. When a spring is stretched, it stores potential energy, which can be released to do work when the spring is released.

The energy associated with the motion of an object is called kinetic energy. It depends on the mass and velocity of the object.

If the work done on an object is zero, it means there is no change in its kinetic energy. However, the object may still have potential energy depending on its position or condition.

The unit of power is the watt (W). It represents the rate at which work is done or energy is consumed.

Force is not a form of energy. It is a physical quantity that causes a change in the motion or shape of an object.

Work and energy are equivalent concepts. Work is a form of energy, and energy is the capacity to do work. The two concepts are deeply interconnected and can be converted from one form to another.