The force that attracts two masses to each other is called

• air resistance
• gravity
• friction
• pressure

Tags

NGSS.MS-PS2-4

A hollow plastic ball and a solid metal ball are dropped from the same height in a vacuum. With no air resistance, gravity is the only force acting on the balls. What do you predict will happen?

• The balls will fall at the same rate
• the metal ball will fall faster
• the plastic ball will fall faster
• the larger ball will fall faster

Tags

NGSS.MS-PS2-4

After a space shuttle is launched into orbit, gravity

• gives it a speed greater than 11,000 m/s
• no longer affects the astronauts on board
• makes it impossible for it to stay in orbit for a long period of time
• continues to pull it forward the center of the Earth

Tags

NGSS.HS-ESS1-4

NGSS.HS-PS2-4

Maria is sliding a box across the floor.  She feels the box resisting her push. The resistance is caused by 

• pressure
• friction
• gravity
• motion

Charles wants to slide a chair across a carpeted floor. He could reduce the effect of friction by 

• placing the chair so that a smaller area is in contact with the floor
• putting a plastic sheet on the floor before he slides the chair
• asking a friend to sit on the chair while he pushes it
• increase the force with which he pushes the chair

Roger is designing a new model rocket. He wants it to have as little air resistance as possible. What should he do?

• decrease its surface area
• lower its temperature
• increase its speed
• makes its surface rougher

Tags

NGSS.MS-ETS1-4

NGSS.MS-PS2-2

To find pressure, you

• multiply the mass by the gravitational constant g
• divide the force by the area over which it is exerted
• divide the total mass by the volume
• multiple the mass by the acceleration

As Lisa climbs a mountain, the air pressure relative to seal level

• increases; there is less air below her than above her
• stays the same no matter how high she climbs
• decreases; there is more air below her than above her
• changes depending on how fast she climbs

The water in a fast moving stream exerts less pressure on the bottom than the water on a slow moving stream. This is an example of 

• pascal's principle
• buoyancy
• density
• Bernoulli's principle

Naomi squeezes the wide end of a tube of toothpaste. The pressure transmitted to the opposite end of the tube is

• equal to the pressure Naomi exerts
• less than the pressure Naomi exerts
• greater than the pressure Naomi exerts
• dependent on the area of the opposite end of the tube