Page 250 - Science Course 3 (Book 1)
P. 250
Mo7-L2a: What is the Law of Conservation of Energy?
Changes Between Kinetic and potential energy
Energy changes between kinetic energy (KE) and potential energy (PE) when a ball is thrown and moves
upward and then downward.
KE PE
Total
Energy
As the ball moves upward, its speed and kinetic As the ball moves downward, potential energy
energy decrease, but the potential energy is decreases. At the same time, the ball’s kinetic
increasing because the ball’s height is increasing. energy increases.
At the ball’s highest point, the gravitational potential When the ball reaches the player’s hand again, its
energy is greatest, and the ball’s kinetic energy is the kinetic energy is at the maximum value again.
least.
The law of Conservation of Energy Key Concept
According to the law of conservation of energy, What is the Law of Conservation of
energy can be transformed from one form into Energy?
another or transferred from one region to another,
but energy cannot be created or destroyed. What is the law of conservation of energy?
Heat Energy
(Atmosphere)
Nuclear Energy
Light Energy
SUMMARY
What is the Law of Conservation of Energy?
Energy can change form, but according t the
Mechanical Chemical law of conversation of energy, energy can
and heat potential energy nerver be created or destroyed.
energy (Photosynthesis)
(Animals)
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