Energy, Work, and Simple Machines Key Vocabulary

These flashcards cover key vocabulary terms related to energy, work, and simple machines, perfect for exam review.

Energy

The ability to cause change or do work.

Kinetic Energy

Energy in the form of motion; depends on mass and velocity.

Potential Energy

Energy that is stored and can be used later.

Elastic Potential Energy

Energy stored in objects that can stretch or compress, such as a rubber band.

Chemical Potential Energy

Energy stored in chemical bonds, like the energy in food.

Gravitational Potential Energy

Energy stored in objects that can fall, such as a ball on a ledge.

Conservation of Energy

Energy cannot be created or destroyed, only changed in form.

Mechanical Energy

The total amount of kinetic and potential energy in a system (ME = KE + PE).

Work

The transfer of energy that occurs when a force makes an object move (W = F × d).

Power

The rate at which work is done (P = W / t).

Machine

A device that makes work easier by increasing force or changing its direction.

Efficiency

A measure of how much work put into a machine is changed into useful output work.

Mechanical Advantage

The ratio of the output force to the input force (MA = F-OUT / F-IN).

Simple Machine

A machine that does work with only one movement, examples include inclined plane, lever, and pulley.

Friction

A force that opposes motion, often converting mechanical energy into thermal energy.

What is the Law of Conservation of Energy?

The Law of Conservation of Energy states that energy cannot be created or destroyed, only transformed from one form to another.

How does an inclined plane make work easier?

An inclined plane reduces the amount of force needed to lift an object by spreading the work over a longer distance.

What is the difference between kinetic energy and potential energy?

Kinetic energy is the energy of motion, while potential energy is stored energy based on an object's position or condition.

Why can’t a machine be 100% efficient?

A machine can’t be 100% efficient due to energy losses from friction, heat, and other forms of energy dissipation.

How does a lever work as a simple machine?

A lever amplifies an input force to lift or move loads by using a fulcrum to provide a point of rotation.

Identify a simple machine found in your home and explain how it works.

A can opener is a lever. When you press the handle down, it pivots on a fulcrum, applying force to puncture and lift the lid off the can, making it easier to open.

Describe a task that would be much harder without simple machines.

Opening a heavy garage door without a pulley system would require significantly more strength and effort, making it difficult to lift.