Definitions
What is the unit of measurement for forces?
A Newton (N)
A balanced force has a net force of ___.
A net force of 0.
Bob pushes a ball with a force of 10N to the right, but is stopped with a tree acting with a force of 30N. What is the net force?
The Net Force is 20N to the left.
An object is in ______________if a position changes when compared to another object
motion
If two forces of equal strength are pushing against each other on a box, will the box move?
No, the forces are equal, so the box will not move.
If Sal lifts a box with a force of 20N, and gravity works against her with a force of 12N. What is the Net Force?
The Net Force is 8N upwards.
This is a contact force that two surfaces exert on each other when they rub.
What is friction?
John is pushing a box with a force of 20N to the right. Friction goes against John with a force of 15N to the left. What is the net force?
The box has a net force of 5N to the right.
If a box has a horizontal net force of 30N, and the force to the right is 40N, what is the force to the left? Does the box move to the right or the left?
The force to the left is 10N, and the box moves to the right.
What is net force?
Net force is a combination of all the forces acting on an object.
Bob tries to push his bookshelf to the right. He pushes with a force of 30N. The bookshelf‘s weight pushes back with a force of 30N. Does the bookshelf move?
No, the net force is 0N so I doesn’t”t move.
If you take a balanced force, add 5N to the right and 8N to the left, what is the net force?
3N to the left.
A place or object used in comparison to determine whether something is in motion.
What is reference point?
If Ellie pushes snowball uphill with a force of 25N. Gravity pushes against her with a force of 20N. Ellie’s brother helps her and pushes it uphill with a force of 30N. Snow falls onto the ball, pushing against them with a force of 25N. What is the net force?
10N uphill.
Richard is making a snowman. It takes 10N to carry the head, 20N to carry the middle, and 30N to carry the bottom. If Richard wanted to move his whole snowman, how much force would he have to use?
60N.