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define force
a push or a pull
define net force
the combination of all forces on an object
What is the net force of figure 2 - C?
0 N
what two things do you need to describe a force?
strength and direction
What is the net force of figure 2 - A? Make sure to give the strength and the direction!
26 N to the right
Describe the motion of the box in figure 2C.
The net force on the box is zero so the motion won't change, it will stay at rest.
Explain how the length of the arrow relates to the strength of the force.
the longer the arrow the stronger the force, the shorter the arrow the less force there is
What is the net force of figure 2 - B? Make sure to give the strength and the direction!
10 N to the right
You push on a desk with a force of 120 N to the right. Your friend pushes on the same desk with a force of 90 N to the left. What is the net force on the desk?
30 N to the right.
What SI unit is force measured in?
Newtons (N)
If there is one force of 3 N to the right and one force of 5 N to the right, what is the net force?
8 N to the right
1b from assess your understanding: your friend increases her force on the desk by 30 N. She doesn't change the direction of her push. What happens to the net force on the desk? Will it accelerate?
The net force becomes 0 N. It won't accelerate.