Energy Changes Quiz

What is the formula for calculating kinetic energy?

• KE = m + v

• KE = 0.5 * m * v

• KE = 0.5 * m * v^2

• KE = m * v^2

State the principle of conservation of energy.

• Energy is only conserved in closed systems.

• Energy conservation is not applicable to real-world scenarios.

• Energy can be destroyed and recreated at will.

• Energy cannot be created or destroyed, only transformed from one form to another.

Explain the difference between kinetic and potential energy.

• Potential energy is the energy stored in an object due to its motion, while kinetic energy is the energy of motion.

• Kinetic energy is the energy stored in an object due to its position or state, while potential energy is the energy of motion.

• Kinetic energy is the energy of motion, while potential energy is the energy stored in an object due to its position or state.

• Potential energy is the energy of motion, while kinetic energy is the energy stored in an object due to its position or state.

A ball is dropped from a height of 10 meters. Calculate its potential energy at the top.

• 50 J

• 98 J

• 120 J

• 75 J

In a closed system, if energy is lost as heat, what happens to the total energy?

• Total energy remains constant

• Total energy increases

• Total energy decreases

• Total energy fluctuates

What is the unit of energy?

• Joule (J)

• Volt (V)

• Watt (W)

• Newton (N)

Define the term 'work' in relation to energy.

• Work is only done when an object is lifted vertically

• Transfer of energy when a force is applied over a distance.

• Work is not related to energy

• Work is the same as power

How does friction affect the energy of a moving object?

• Friction increases the energy of a moving object by providing additional force

• Friction reduces the energy of a moving object by converting some of its kinetic energy into heat energy.

• Friction has no impact on the energy of a moving object

• Friction decreases the energy of a moving object by increasing its kinetic energy

Calculate the kinetic energy of a car with a mass of 1000 kg moving at 20 m/s.

• 200,000 J

• 50,000 J

• 400,000 J

• 100,000 J

Describe the energy changes that occur when a pendulum swings back and forth.

• Energy changes from potential to kinetic and back as the pendulum swings.

• Energy changes from kinetic to potential as the pendulum swings.

• Energy changes from thermal to electrical as the pendulum swings.

• Energy changes from sound to light as the pendulum swings.