Work and Power

Front

What is work in physics?

Back

Work is defined as the product of the force applied to an object and the distance over which that force is applied, in the direction of the force. It is calculated using the formula: Work (W) = Force (F) × Distance (d) × cos(θ), where θ is the angle between the force and the direction of motion.

Front

What is the unit of work?

Back

The unit of work is the Joule (J), which is defined as the amount of work done when a force of one newton displaces an object by one meter in the direction of the force.

Front

What is power in physics?

Back

Power is the rate at which work is done or energy is transferred over time. It is calculated using the formula: Power (P) = Work (W) / Time (t).

Front

What is the unit of power?

Back

The unit of power is the Watt (W), which is defined as one joule per second (1 W = 1 J/s).

Front

What happens when the direction of the applied force is opposite to the direction of motion?

Back

Negative work is done when the direction of the applied force is anti-parallel (opposite) to the direction of motion.

Front

How do you calculate work done when a force is applied?

Back

Work done can be calculated using the formula: Work (W) = Force (F) × Distance (d) × cos(θ), where θ is the angle between the force and the direction of motion.

Front

Is work done when an object is held still?

Back

No, work is not done when an object is held still, as there is no displacement.

Front

How do you calculate the time needed to do a certain amount of work with a given power?

Back

Time can be calculated using the formula: Time (t) = Work (W) / Power (P).

Front

What is the relationship between work and power?

Back

Power is the rate at which work is done. More power means work is done in less time.

Front

If a weightlifter holds a barbell still above his head, is work done?

Back

False, no work is done because there is no displacement of the barbell.