post test Gravity and Kinetic Energy

If a car travels a distance of 100 kilometers (km) in 2 hours, what is its average speed?

• 50 km per hour

• 200 km per hour

• 0.2 km per hour

• More information is needed to know the average speed.

A ball rolls slowly to the edge of a building’s roof. Which of the following best describes the ball’s motion after it passes the edge of the roof?

• The ball falls at a constant speed of about 1 meter per second per second

• The ball falls at a constant speed of about 10 meters per second.

• The ball falls with a speed that increases by about 1 meter per second

• The ball falls with a speed that increases by about 10 meters per second per second

Tags

NGSS.MS-PS2-4

NGSS.MS-PS3-5

An object is moving at a constant speed. Every second, the object’s speed is measured. At 2 seconds (s), a single constant force begins to slow the object down. This force continues to act upon the object during the remaining time shown in the table. Which row of the following table could be a correct representation of the object’s speed after each second?

• A

• B

• C

• D

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NGSS.MS-PS2-2

Acceleration is ______________________.

• going faster and faster

• going slower and slower

• change in speed over time

• going really fast

A bag of potatoes has a mass of 2.5 kilograms (kg). What is its approximate weight on Earth? (Mark the one best answer.) Weight = mass X g(9.8 m/s)

• 25 newtons

• 25 pounds

• 25 calories

• An object’s mass is the same as its weight.

Tags

NGSS.MS-PS2-4

Two students are playing on a teeter-totter during recess. Which one has more potential energy? (Mark the one best answer.)

• Student A has more potential energy

• Student B has more potential energy.

• They have the same amount of potential energy

• More information is needed to determine which student has more potential energy

Tags

NGSS.MS-PS2-4

NGSS.MS-PS3-2

Explain how the mass and the speed of the moving vehicle affects a collision.

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NGSS.MS-PS2-1

NGSS.MS-PS2-2

NGSS.MS-PS3-1

Two children are sledding down a hill. Child X is 7 centimeters taller than child Y, but they both weigh the same, and both of their sleds weigh the same. If they are sledding at the same speed, which one has more kinetic energy?

• Child X has more kinetic energy.

• Child Y has more kinetic energy

• Both of them have the same amount of kinetic energy

• More information is needed to determine which child has more kinetic energy.

Tags

NGSS.MS-PS3-1

NGSS.MS-PS3-5

The gravitational force on Saturn is 1.07 g. Compare the weight of a 100-kg astronaut on Earth and on Saturn.

• The astronaut will weigh more on Saturn than on Earth

• The astronaut will weigh less on Saturn than on Earth.

• The astronaut will weigh the same on Saturn as on Earth.

• More information is needed to compare the astronaut’s weight on Saturn and Earth.

Tags

NGSS.MS-PS2-4

Pocket billiards is a game in which players use sticks, called cues, to put the white cue ball into motion. The goal is for the cue ball to collide with the other balls and make them roll into any of the six pockets on the corners and sides of the table. a. Which science concept is most likely to help you effectively play a game of billiards?

• Energy cannot be created or destroyed, only transferred. (Conservation of energy)

• The weight of a ball depends on the ball’s mass and the force of gravity. (De nition of Weight)

• For every action, there is an equal and opposite reaction. (Newton’s third law

• An object either remains at rest or continues to move at a constant speed, unless acted upon by a force. (Newton’s  rst law)

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2