Understanding Work, Power, and Energy

What is the formula for calculating kinetic energy (KE)?

Which of the following is the unit of power in the International System of Units (SI)?

• Joule

• Watt

• Newton

• Pascal

• 49 J

• 98 J

• 490 J

• 980 J

If a car accelerates from rest to a velocity of 20 m/s, what is the change in its kinetic energy? (Assume the mass of the car is 1000 kg)

• 200,000 J

• 100,000 J

• 400,000 J

• 800,000 J

Explain why a pendulum eventually comes to a stop if no external force is applied.

• Due to gravitational force

• Due to air resistance and friction

• Due to magnetic forces

• Due to increase in potential energy

A machine does 500 J of work in 10 seconds. What is its power output?

• 5 W

• 50 W

• 500 W

• 5000 W

Which of the following statements is true about work done by a force?

• Work is done only when the force is perpendicular to the displacement.

• Work is done only when the force is parallel to the displacement.

• Work is done only when there is no displacement.

• Work is done only when the force is opposite to the displacement.

A 2 kg object is moving with a velocity of 3 m/s. Calculate its kinetic energy.

• 3 J

• 6 J

• 9 J

• 18 J

Discuss the relationship between work and energy in the context of a moving object.

• Work is the energy required to stop the object.

• Work is the energy transferred to or from an object via the application of force along a displacement.

• Work is the energy lost by the object due to friction.

• Work is the energy stored in the object.

What happens to the potential energy of an object as it is raised to a higher elevation?

• It decreases

• It remains constant

• It increases

• It becomes zero