Work-Energy Theorem

Front

What is the Work-Energy Theorem?

Back

The Work-Energy Theorem states that the net work done by the forces acting on an object is equal to the change in its kinetic energy.

Front

Define kinetic energy (KE).

Back

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

Front

What is the formula for calculating work done (W)?

Back

Work done is calculated using the formula W = Fd cos(θ), where F is the force applied, d is the distance moved, and θ is the angle between the force and the direction of motion.

Front

What is the relationship between net work and kinetic energy?

Back

The net work done on an object is equal to the change in its kinetic energy (ΔKE = KE_final - KE_initial).

Front

If a baseball is hit with a force of 6000 N and travels 120 m, how do you calculate the work done?

Back

Work done (W) = Force (F) x Distance (d) = 6000 N x 120 m = 720000 J.

Front

True or False: The net work done on a body is equal to its change in kinetic energy.

Back

True.

Front

How do you calculate the force required to accelerate an object?

Back

Force can be calculated using Newton's second law: F = ma, where m is mass and a is acceleration.

Front

What is the significance of the Work-Kinetic Energy Theorem?

Back

The Work-Kinetic Energy Theorem emphasizes that the work done on an object results in a change in its kinetic energy.

Front

What does it mean if the work done on an object is zero?

Back

If the work done is zero, it means there is no change in the object's kinetic energy, indicating that the object is either at rest or moving at a constant velocity.

Front

Calculate the change in kinetic energy if a car accelerates from 0 to 25 m/s and has a mass of 1000 kg.

Back

ΔKE = 1/2 m(v_final² - v_initial²) = 1/2 (1000 kg)(25 m/s)² = 312500 J.