8th Review

What is a force?

• a pull exerted on an object

• a change in the direction of motion of an object

• a measure of how heavy an object is

• a push or pull exerted on an object

Tags

NGSS.3-PS2-1

If two opposing players are trying to move a soccer ball, why is it not moving?

• unbalanced forces are acting on the ball

• balanced forces are acting on the ball

• one player's force is stronger than the other player's force

• one player's force is weaker than the other player's force

Tags

NGSS.MS-PS2-2

If you pull a box across the floor at constant speed, why doesn't the motion of the box change?

• If you weren't pulling, there would be no force, and the box would stop moving.

• Your force on the box is balanced by frictional force.

• Your force on the box is balanced by gravitational force.

• If you weren't pulling on the box, there would be no force, and the box would speed up.

Tags

NGSS.MS-PS2-2

If two opposing players are both trying to move a soccer ball, how can one player make it move?

• Push the ball harder.

• Stop the ball.

• Push the ball in a different direction.

• Put a foot on top of the ball.

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

An asteroid will curve toward the sun when it enters our solar system; why does the sun not move toward the asteroid?

• The asteroid is moving too quickly to exert a large force on the sun.

• There is no force exerted on the sun.

• The forces are equal, but the sun is too massive to react to the force exerted.

• There is no force exerted on the comet or the sun unless there is a collision.

Tags

NGSS.MS-ESS1-2

NGSS.MS-PS2-4

NGSS.MS-PS2-5

Which forces are non-contact forces?

• Gravity

• Friction

• Air Resistance

• Magnetic force

Tags

NGSS.MS-PS2-3

NGSS.MS-PS2-4

NGSS.MS-PS2-5

If the box is being pulled from both directions, which way will it move?

• It will move to the left.

• It will move to the right.

• It will not move at all.

• It will move right, then left.

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

When you throw a basketball at the basket and hit the rim, the rim will move backwards, and the basketball will bounce back toward you. . . why does the ball bounce back?

• The ball exerts a smaller force on the rim because the ball is smaller.

• The ball exerts a larger force on the target because the ball is moving faster.

• The target exerts the same size force on the ball, so they have opposite and equal reactions.

• The target exerts a larger force on the ball because the ball is bouncy.

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

If a car traveled 400 miles in 8 hours, what is its average speed?

• 40 mph

• 70 mph

• 50 mph

• 60 mps

What is the acceleration of a car that accelerated from rest to 20 m/s in 30 seconds?

• 1.5 m/s²

• 0.23 m/s²

• 1.0 m/s²

• 0.67 m/s²

Tags

NGSS.MS-PS2-2