Work, energy & power - CIE IGCSE Physics

Front

What is the formula for calculating work?

Back

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 in the International System of Units (SI)?

Back

The unit of work is the joule (J).

Front

How is kinetic energy defined?

Back

Kinetic energy (KE) is the energy an object possesses due to its motion, calculated as KE = 1/2 mv², where m is mass and v is velocity.

Front

What is potential energy?

Back

Potential energy (PE) is the energy stored in an object due to its position or configuration, commonly calculated as PE = mgh, where m is mass, g is acceleration due to gravity, and h is height.

Front

What is the relationship between work and energy?

Back

Work done on an object results in a change in its energy. If work is done on an object, its energy increases.

Front

What is power in the context of work and energy?

Back

Power is the rate at which work is done or energy is transferred, calculated as Power (P) = Work (W) / Time (t).

Front

How do you calculate gravitational potential energy?

Back

Gravitational potential energy (PE) can be calculated using the formula PE = mgh, where m is mass, g is the acceleration due to gravity (approximately 9.81 m/s²), and h is height.

Front

What is the difference between work done against gravity and work done against friction?

Back

Work done against gravity involves lifting an object to a height, while work done against friction involves moving an object across a surface, overcoming resistance.

Front

What is the principle of conservation of energy?

Back

The principle of conservation of energy states that energy cannot be created or destroyed, only transformed from one form to another.

Front

How does increasing the speed of an object affect its kinetic energy?

Back

Kinetic energy increases with the square of the speed; doubling the speed results in four times the kinetic energy.