Static and Kinetic Friction

What type of friction is shown in this car that is at rest?

• rolling

• static

• fluid

• sliding

What is teh relationship between the force of static friction and the force of kinetic friction between two surfaces?

• Static frictional force is always greater.

• Kinetic frictional force is always greater.

• Static and kinetic frictional forces are always equal.

Friction is a force that acts in an ___________ direction of movement.

• similar

• opposite

• parallel

• north

Which of the following factors affect the amount of friction between two objects?

• type of surface & pressure applied to the surface

• distance between the objects

• mass of the objects

• temperature of the objects

Why do you need to apply more force to start moving an object from rest compared to keeping it moving?

• Static friction is generally higher than kinetic friction

• Kinetic friction is generally higher than static friction

• Objects gain energy when they start moving

• Objects are lighter when in motion

Tags

DOK Level 2: Skill/Concept

In the diagram below, a girl sits on a sled and slides down a hill of snow. The arrow that represents the force of friction opposing the motion of the sled down the hill is (a)   .

• Arrow A

• Arrow B

• Arrow C

• Arrow D

A force that resists the movement of one surface past another surface.

• Acceleration

• Gravity

• Friction

• Lubricant

What are 2 factors that determine the amount of friction between 2 objects?

• Force and roughness between surfaces

• hills and valleys and how smooth or rough the surface is

• Amount of force and amount of surface the comes in contact

• The force and the weight exerted on the surfaces

What is the force of friction between a block of ice that weighs 950 N and the ground if μ = .12?

• 65 N

• 226 N

• 175 N

• 114 N

Tags

NGSS.MS-PS2-2

What is the coefficient of static friction if it takes 44 N of force to move a box that weighs 86 N? 

• 0.78

• 0.51

• 0.78 N

• 0.58 N

Tags

NGSS.MS-PS2-2