Friction and Gravity

Friction is the force that two exert on each other when they rub against each other.

• True

• False

The strength of the force depends on two factors: how hard the surfaces push together and the type of surfaces involved.

• True

• False

Fluid friction occurs when an object rolls across a surface.

• True

• False

Static friction acts on objects that are not moving.

• True

• False

Sliding friction occurs when two solid surfaces slide over each other.

• True

• False

When a solid object moves through a fluid, a rolling friction happens.

• True

• False

A force that pushes objects away from each other is gravity.

• True

• False

Tags

NGSS.MS-PS2-4

Mass and distance are two factors affect the gravitational attraction between objects.

• True

• False

Tags

NGSS.MS-PS2-4

Choose all answers that tells you the differences between weight and mass.

• Weight varies with the strength of gravitational force.

• Mass depends on the force of gravity on a person or or object at the surface of a planet.

• Mass varies with the strength of gravitational force.

• Weight is the force of gravity on a person or or object at the surface of a planet.

Why do objects accelerate during free fall?

• In free fall, the force of gravity is an unbalanced force, which causes an object to accelerate.

• In free fall, the force of gravity is an balanced force, which causes an object to slow down.

• In free fall, the force of gravity is an unbalanced force, which causes an object to stop..

• In free fall, the force of gravity is an balanced force, which causes an object to stop.

Tags

NGSS.MS-PS2-4