Page 13 - Science Course 2 (Book 2)

Mo8-L1b: How Does Gravity Affect Forces?
Mo8-L1b How Does Friction Affect Forces?
KEY CONCEPTS:
1. How does friction affect the motion of two
objects sliding past each other?
Vocabulary A-Z
Let us learn some vocabulary
weight
the gravitational force exerted on an object.
friction
a contact force that resists the sliding motion of two
surfaces that are touching.
Let’s Begin
What is Gravity?
The strength of force depends on the mass of each
object and the distance between them.
When the mass of one or both objects increases, the
gravitational force between them also increases.
Weight is the gravitational force exerted on an object.
Near Earth’s surface, an object’s weight is the
gravitational force exerted on the object by Earth.
Because weight is a force,
it is measured in newtons.
1KG
Weight = pull of 10N
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