Energy and Forces
Energy and motion
What energy is
Energy is the ability to do work or cause change. It can appear in many forms, such as motion, heat, light, sound, and chemical energy. Energy can be transferred from one object to another.
Important idea
Energy is not the same as force. A force pushes or pulls; energy is the capacity to cause change.
Forces
A force is a push or pull. Forces can make objects speed up, slow down, change direction, or change shape. Gravity is a force that pulls objects toward Earth.
Common force ideas
Which is an example of a force?
A push is a force because it can change motion.
Correct answer: A push on a door
Motion and speed
Speed tells how fast something moves. A simple formula is . If an object travels meters in seconds, its speed is meters per second.
What is the difference between force and energy?
Forces act on objects, while energy describes the capacity to make things happen.
Correct answer: A force is a push or pull; energy is the ability to cause change.
What does friction usually do?
Friction opposes motion between surfaces.
Correct answer: Resists motion
Thinking about motion
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Step 1: Choose an object
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Step 2: Notice whether it is speeding up, slowing down, or changing direction
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Step 3: Identify forces acting on it
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Step 4: Predict what happens if the forces change