Forces at Angles, Inclines and Friction

 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

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.MS-PS2-2

NGSS.MS-PS2-4

When looking at friction problems, if the net force in the x-direction on an object is zero, what can we say about its acceleration?

• it is positive

• it is negative

• it is zero

• not enough information is given

Tags

NGSS.MS-PS2-2

Normal force is

• Always opposite the weight

• Always parallel and down the incline

• Always perpendicular to the surface

• It depends on the direction of motion

Which of the following is the best expression for the Normal Force?

• F_N = mg cos(ϴ)

• F_N = mg sin(ϴ)

• F_N = mg sin(180-ϴ)

• F_N = mg cos(90-ϴ)

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

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 (parallel to the ramp)?

• 0N

• 2.1N

• 7.7N

• 8.0N

Tags

NGSS.MS-PS2-2

A 1.0 × 10⁵-newton truck at rest on a hill that makes an angle of 8.0° with the horizontal. What is the component of the truck’s weight parallel to the hill?

• 1.4E3N
• 1E4N
• 1.4E4N
• 9.9E4N

Tags

NGSS.MS-PS2-2

A cart rolls down an inclined plane with constant speed as shown in the diagram below. Which arrow represents the direction of frictional force?

• A
• B
• C
• D

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

A 10.-newton block is sliding down a 30-degree incline at a constant speed. What is the force of friction?

• 5N
• 4.9N
• 10N
• 98N

Tags

NGSS.MS-PS2-2