Mechanical Energy*

What is the principle of conservation of mechanical energy?

• The principle states that in a closed system, the total mechanical energy (potential + kinetic) remains constant if only conservative forces are acting.

• The principle states that energy can be created and destroyed in a closed system.

• The principle states that mechanical energy is always converted into thermal energy in a closed system.

• The principle states that the total energy of a system is always increasing over time.

What is the relationship between potential energy and kinetic energy in a roller coaster?

• As a roller coaster climbs, potential energy decreases and kinetic energy increases.

• As a roller coaster climbs, potential energy increases and kinetic energy decreases.

• As a roller coaster climbs, potential energy increases and as it descends, potential energy converts to kinetic energy, increasing speed.

• Potential energy and kinetic energy are unrelated in a roller coaster.

What is friction and how does it affect mechanical energy?

• Friction is a force that enhances motion and increases mechanical energy.

• Friction is a force that opposes motion and can convert mechanical energy into thermal energy, reducing the total mechanical energy in a system.

• Friction is a type of energy that is always beneficial to mechanical systems.

• Friction is a force that has no effect on mechanical energy.

What is potential energy?

• The energy of an object in motion.

• The energy stored in an object due to its position or state.

• The energy released during a chemical reaction.

• The energy associated with the temperature of an object.

What is kinetic energy?

• The energy of an object due to its motion, calculated using the formula KE = 1/2 mv².

• The energy stored in an object at rest due to its position.

• The energy released during a chemical reaction.

• The energy associated with the temperature of an object.

What is the formula for calculating potential energy?

• PE = mv^2

• PE = mgh

• PE = 1/2 mv^2

• PE = mg^2h

What is an example of a situation where mechanical energy is transformed?

• When a diver jumps off a diving board, their potential energy at the top transforms into kinetic energy as they fall.

• When a car accelerates from a stop, converting fuel into motion.

• When a spring is compressed and then released, causing an object to move.

• When a ball is thrown into the air, gaining potential energy as it rises.

What is mechanical energy?

• The energy associated with the motion and position of an object, which is the sum of potential energy and kinetic energy.

• The energy stored in an object due to its height above the ground.

• The energy that is transferred when an object is in motion.

• The energy that is released during a chemical reaction.

What is the effect of mass on kinetic energy?

• Kinetic energy decreases with mass.

• Kinetic energy remains constant regardless of mass.

• Kinetic energy increases with mass.

• Kinetic energy is independent of speed.

How does height affect potential energy?

• The higher an object is, the more potential energy it has.

• Height has no effect on potential energy.

• Potential energy decreases as height increases.

• Potential energy is inversely proportional to height.