Work and Energy

What factors determine the kinetic energy of an object in motion?

• The mass of the object and its velocity

• The position of the object and its potential energy

• The temperature of the environment and the time of motion

The kinetic energy of an object is defined as the energy associated with its motion.

• true

• false

Which of the following statements accurately describes potential energy?

• Potential energy is the energy possessed by an object due to its motion.

• Gravitational potential energy is directly proportional to the height of an object above the ground.

• Potential energy remains constant in a system regardless of external factors.

When an object slides on a surface, what is true about the work done by friction?

• Friction always does positive work on the object

• Friction always does negative work on the object

• Friction never does any work on the object

Which of the following statements best describes the conservation of mechanical energy in a system?

• Mechanical energy is conserved as long as the system's velocity remains constant

• The conservation of mechanical energy applies only to systems with kinetic energy and no potential energy

• The sum of kinetic and potential energies remains constant as long as no non-conservative forces are acting on the system

The work done by a constant force is calculated as the product of displacement and the component of the force in the direction of displacement

• true

• false

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

• Joule (J)

• Watt (W)

• Newton (N)

Which of the following statements accurately describes elastic potential energy?

• Elastic potential energy is the energy stored in an object due to its position above the ground

• The amount of elastic potential energy stored in a spring depends only on the material it is made of

• Elastic potential energy is stored in an object that is compressed, stretched, or deformed

A ball is thrown straight up into the air. At the highest point of its trajectory, which of

the following statements regarding its potential and kinetic energy is true?

• The potential energy is at its maximum, while the kinetic energy is zero

• The potential energy is zero, while the kinetic energy is at its maximum

• Both potential and kinetic energy are at their maximum

When a spring is compressed or stretched, what happens to its potential energy?

• The potential energy of the spring remains constant

• The potential energy of the spring increases when it is compressed and decreases when it is stretched

• The potential energy of the spring decreases when it is compressed and increases when it is stretched