Dynamic Physics Review

An object with a mass of m is thrown straight up near the surface of the earth. While the object is going up, the net force on it is

• zero

• less than mg

• equal to mg

• more than mg

Tags

NGSS.MS-PS2-2

NGSS.MS-PS2-4

The total number of forces acting on a box that is being pushed across a rough table at constant velocity is

• 1

• 2

• 3

• 4

Tags

NGSS.MS-PS2-2

An object has a mass of m and a weight of Wmoon while it is on the moon, where the acceleration due to gravity is 1.6 m/s2. What will be the weight of the object when it is brought to the earth?

• W earth > w moon

• w moon > w earth

• w earth = w moon

• it is impossible to know what the weight will be

Tags

NGSS.MS-PS2-2

NGSS.MS-PS2-4

An object moving at a constant velocity near the surface of the earth is influenced by…

• a constant net force

• zero net force

• no forces

• cannot be determined without more information

A large truck collides with a small car causing a lot of damage to the small car. Considering that more damage is done to the car, during the collision:

• The force acting on the truck is greater than the force acting on the car.

• The force acting on the truck is less than the force acting on the car.

• The force acting on the truck is equal to the force acting on the car.

• The relative size of the forces will depend on how the details of how they collided.

Tags

NGSS.MS-PS2-1

An object with a mass of m hangs from a string that is attached to the ceiling. The string pulls up on the object with force, mg, which we call the action force. According to Newton’s 3rd law, what is the reaction force?

• The earth pulling down on the object with force mg.

• The object pulling up on the earth with force mg.

• The object pulling down on the string with force mg.

• The string pulls down on the ceiling.

On a rough surface, it is easier to keep an object moving that get it started because:

• us > uk

• us< uk

• the normal force is greater when the carton is at rest

• initially the normal force is not perpendicular to the applied force

A person, of weight mg, is standing on a scale in an elevator. What will the scale read when the elevator is moving upward at a constant velocity?

• More than mg

• less than mg

• equal to mg

• cannot tell what scale will read

Tags

NGSS.MS-PS2-2

A person, of weight mg, is standing on a scale in an elevator. What will the scale read when the elevator accelerates downward?

• more than mg

• less than mg

• equal to mg

• cannot tell what the scale will read

Tags

NGSS.MS-PS2-2

NGSS.MS-PS2-4

When the rocket engines on the space shuttle are suddenly turned off, while traveling in empty space, the space shuttle will

• stop immediately

• slowly slow down and then stop

• go faster and faster

• move with constant speed