Which of the following is an example in which you are traveling at constant speed, but not at constant velocity?

• rolling freely down a hill in a cart, traveling in a straight line

• driving backward at exactly 50 km/hr

• driving around in a circle at exactly 100 km/hr

• jumping up and down exactly 60 times per minute

• none of the above

Which of the following correctly states the value and units of the acceleration of gravity on Earth?

• 9.8 m/s2

• 9.8 m/s

• 9.8 km/s2

• 9.8 m2/s

• 9.8 km/s

Tags

NGSS.MS-PS2-4

Momentum is defined as

• mass times speed.

• mass times velocity.

• force times velocity.

• mass times acceleration.

• force times acceleration.

If an object's velocity is doubled, its momentum is

• halved.

• unchanged.

• doubled.

• quadrupled.

• dependent on its acceleration.

Tags

NGSS.HS-PS2-2

As long as an object is not gaining or losing mass, a net force on the object will cause a change in

• acceleration.

• direction.

• weight.

• speed.

• velocity.

Tags

NGSS.MS-PS2-2

If your mass is 60 kilograms on Earth, what would your mass be on the Moon?

• 10 pounds

• 10 kilograms

• 360 kilograms

• 60 kilograms

• 60 pounds

In which of the following cases would you feel weightless?

• while walking on the Moon

• while falling from an airplane with your parachute open

• while traveling through space in an accelerating rocket

• while falling from a roof

• none of the above

Tags

NGSS.MS-PS2-4

NGSS.MS-PS2-5

Under what conditions is an object weightless? (Ignore effects of air resistance.)

• when it is in free-fall

• when it is on the Moon

• when it is detached from Earth's surface (such as in an airplane)

• when it is moving in at constant velocity

Astronauts are weightless inside the International Space Station because

• the station and the astronauts are constantly falling toward Earth.

• the station has rockets that fire to counteract Earth's gravity.

• there is no gravity in space.

• the station is too far from Earth for gravity to be noticeable.

You are standing on a scale in an elevator and notice that your weight is lower than your normal weight. What do you conclude is occurring?

• The elevator is accelerating upward.

• The elevator is moving at a constant velocity upward.

• The elevator is accelerating downward.

• The elevator is moving at a constant velocity downward.

• Your diet is working.

Tags

NGSS.MS-PS2-2

NGSS.MS-PS2-4