Unit 3 Force and Motion

A motorcycle is being driven on a road moving north at 40 miles per hour. A car is driving on the same road moving south at 40 miles per hour. Which of the following is true?

• The motorcycle and the car are moving in opposite directions, so their velocities are different.

• The motorcycle and the car are moving in opposite directions, so their speeds are different.

• The motorcycle and car are moving at the same velocity but different speeds.

• The motorcycle and car are moving at the same velocity and the same speed.

Todd and Angela set up a ramp and released several cars from the top. If Todd and Angela want to determine the average speed of their cars down the ramp, what information do they need?

• acceleration from rest and distance down the ramp

• distance down the ramp and time down the ramp

• time down the ramp and acceleration from rest

• direction of motion and time down the ramp

Tags

NGSS.MS-PS3-1

An object with increasing acceleration is also increasing in which other property?

• mass

• temperature

• velocity

• volume

Tags

NGSS.MS-PS3-1

An object that is traveling east at a constant rate has

• velocity, but neither acceleration nor speed.

• speed, but neither velocity nor acceleration.

• speed and velocity, but no acceleration.

• acceleration and speed, but no velocity

Victoria and Claire are playing a game of tug-of-war, but the flag tied to the center of the rope is NOT moving. What is happening to the rope in this game?

• Victoria is applying more force in one direction.

• Claire is applying more force in one direction.

• Victoria and Claire are applying equal forces in the same direction.

• Victoria and Claire are applying equal forces in opposite directions

Tags

NGSS.MS-PS2-2

A ball rolls down from the top of a grassy hill, reaches the bottom of the hill, continues to roll, and then starts to slow down and comes to a stop. What forces caused this ball's motion?

• Frictional force caused the ball to roll down the hill, but magnetism caused the ball to slow down and stop.

• Magnetic force caused the ball to roll down the hill, but air resistance caused the ball to slow down and stop.

• The force of the hill caused the ball to roll down the hill, but gravity caused the ball to slow down and stop.

• Gravity caused the ball to roll down the hill, but frictional force caused the ball to slow down and stop.

Tags

NGSS.MS-PS2-2

NGSS.MS-PS2-4

Unbalanced forces

• make an object move opposite the applied force.

• can change an object's speed but not direction.

• maintain the constant motion of an object.

• cause the motion of an object to change.

Tags

NGSS.MS-PS2-2

Katrina pushes off a flat sidewalk on her new skateboard. What causes her to move?

• The force of her push overcomes the forces of gravity and friction.

• The force of gravity overcomes the forces of her push and friction.

• The force of friction overcomes the normal force of the skateboard and the force of gravity.

• The normal force of the skateboard overcomes the force of her push and the force of gravity

Tags

NGSS.MS-PS2-2

Suppose 15 children who weigh the same are playing a game of tug-of-war. Five children pull with 5 newtons of force, while ten children pull with 10 newtons of force in the opposite direction. How can one determine the net force on the rope?

• The forces are in the same direction, so the newtons can be added.

• The forces are in opposite directions, so the newtons can be divided.

• The forces are in opposite directions, so the newtons can be subtracted.

• The newtons are in the same direction, so the newtons can be multiplied.

Tags

NGSS.MS-PS2-2

If the net force on an object is zero, then what is true about the object?

• The forces applied to it are only reaction forces.

• The forces applied to it are only action forces.

• The forces applied to it are unbalanced.

• The forces applied to it are balanced