Coefficients of Friction

 What is the unit called that measures force?

• weight
• meter
• Newton
• kilogram

What does friction produce?

• light
• sound
• heat
• gravity

Tags

NGSS.MS-PS3-5

What direction does friction act relative to motion?

• in the same direction
• in the opposite direction 
• need more information
• depends on the force

 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

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.HS-PS2-1

A box takes 40 N to start moving when the coefficient of static friction is .54. What is the weight of the box? 

• 81 N
• 18 N
• 98 N
• 74 N

Tags

NGSS.HS-PS2-1

What are the units on the coefficient of friction?

• none
• Newtons
• meters
• kilograms

What type of friction is not moving?

• static
• sliding
• fluid
• rolling

Which of the following is an example of friction that is helpful?

• Brakes used on a bike
• Tires from a car on the road
• Tread on the bottom of your shoes
• All are examples that are helpful

F_N=100N, F_f=20N

• μ=5.0

• μ=0.2

• μ=1.2

• μ=0.1