Section 1
Forces Create Work When Objects Move
Work happens when a force changes an object's motion or position. Pushing a wall isn't work because nothing moves, but lifting a book is work because the force changes its position.
In this Grade 3 lesson from Science: A Closer Look, Chapter 6, students learn the scientific definitions of work, energy, kinetic energy, and potential energy, discovering that work occurs only when a force changes an object's motion. Students explore how energy is the ability to do work and how potential energy converts to kinetic energy through real-world examples like a sled going downhill.
Section 1
Forces Create Work When Objects Move
Work happens when a force changes an object's motion or position. Pushing a wall isn't work because nothing moves, but lifting a book is work because the force changes its position.
Section 2
Energy Powers Our Ability to Work
Energy is the ability to do work. Objects must have energy to move. Kinetic energy powers moving objects, while potential energy is stored and ready to be used later.
Section 3
Energy Transfers Between Objects
Energy moves from one object to another. When you roll a bowling ball, energy transfers from your body to the ball and then to the pins when they collide.
Section 4
Energy Changes Forms During Activities
Energy can transform from one type to another. When you rub your hands together, motion energy changes to heat energy because of friction, making your hands feel warmer.
Section 5
Foods Store Energy for Our Bodies
Foods contain stored energy measured in calories. Different activities use different amounts of energy. Your body converts food's potential energy into motion when you bike, jog, or play.
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Section 1
Forces Create Work When Objects Move
Work happens when a force changes an object's motion or position. Pushing a wall isn't work because nothing moves, but lifting a book is work because the force changes its position.
Section 2
Energy Powers Our Ability to Work
Energy is the ability to do work. Objects must have energy to move. Kinetic energy powers moving objects, while potential energy is stored and ready to be used later.
Section 3
Energy Transfers Between Objects
Energy moves from one object to another. When you roll a bowling ball, energy transfers from your body to the ball and then to the pins when they collide.
Section 4
Energy Changes Forms During Activities
Energy can transform from one type to another. When you rub your hands together, motion energy changes to heat energy because of friction, making your hands feel warmer.
Section 5
Foods Store Energy for Our Bodies
Foods contain stored energy measured in calories. Different activities use different amounts of energy. Your body converts food's potential energy into motion when you bike, jog, or play.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter