friction and inclined planes, review

If an object is at rest on an inclined plane, which of the following forces is greatest?

• Normal Force
• Friction
• Weight
• Both Normal Force and Weight are equal, so they both are the greatest.

Tags

NGSS.HS-PS2-1

 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.HS-PS2-1

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 force due to friction?

• none
• Newtons
• meters
• kilograms

A hockey puck slides on ice at a constant velocity. What is the net force acting on the puck?

• Zero
• Equal to its weight
• Less than its weight but greater than zero
• Depends on the speed of the puck

Tags

NGSS.HS-PS2-1

  A 220 Kg crate is pushed horizontally with a force of 700 N. If the coefficient of kinetic friction is 0.20, calculate the acceleration of the crate.   

• 1.02 m/s²
• 1.22 m/s²
• 1.42 m/s²
• 1.62 m/s²

Tags

NGSS.HS-PS2-1

A box weighing 46 newtons rests on an incline that makes an angle of 25° with the horizontal. What is the magnitude of the component of the box’s weight perpendicular to the incline?

• 19N
• 21N
• 42N
• 26N

Tags

NGSS.HS-PS2-1

When the sum of all the forces acting on a block on an inclined plane is zero, the block

• must be at rest
• must be accelerating
• may be slowing down
• may be moving at a constant speed

Tags

NGSS.HS-PS2-1

An 8.0-newton block is accelerating down a frictionless ramp inclined at 15° to the horizontal. What is the magnitude of the net force causing the block’s acceleration?

• 0N
• 2.1N
• 7.7N
• 8.0N

Tags

NGSS.HS-PS2-1