Friction

Which is larger, static coefficient or kinetic coefficient of friction?

• static

• kinetic

• neither, they are always the same

• it depends on the material

What is the weight of a 5kg object

• 5kg

• 5 N

• about 50 N

• about half a N

Tags

NGSS.HS-PS2-1

How much force would it take to move a 3kg object from rest? (μ = 0.5 and 0.1)

• about 150N

• about 300N

• about 3 N

• about 15 N

Tags

NGSS.HS-PS2-1

The coefficient of static friction is about 1.0 so the critical angle would be

• 31 degrees

• 45 degrees

• 19 degrees

• 67 degrees and partly cloudy

A box is sitting on an incline and begins to slide at about 30 degrees. The coefficient of friction is about

• 0.6

• 1.1

• 0.36

• 0.2

Tags

NGSS.HS-PS2-1

Which of the following means "force that holds the two surfaces together"?

• normal force

• parallel force

• friction

• centrifugal force

Normal and parallel forces are two parts of which larger force?

• impulse

• centrifugal

• weight

• friction

μ represents

• the roughness of the surfaces

• the force pulling parallel to the surface

• the mass of the object

• the total force of friction

Which of the following is NOT a cause of friction?

• imperfections crashing together

• imperfections meshing together at rest

• molecular bonding

• lubrication

When an object is on an incline and the angle gets bigger which force also gets larger?

• Ff

• Fn

• Fp

• centripetal

Tags

NGSS.HS-PS2-1