2D Forces

A sled is at rest on a slope, held by a rope attached to a pole, as shown. Which forces should be shown on a Free Body Diagram for the sled?

• gravity and the tension in the rope

• gravity, the tension in the rope, and the normal force

• gravity only

• gravity, the tension in the rope, the normal force, and the net force

Tags

NGSS.HS-PS2-1

A tugboat is attached to a barge of mass 5100 kg with cable #1. A second barge with a mass of 12 000 kg is attached to the first barge with cable #2. The tugboat pulls the two barges with an acceleration of 0.030 m/s2. What are the tensions in cables #1 and #2?

• cable #1: 510 N; cable #2: 360 N

• cable #1: 360 N; cable #2: 510 N

• cable #1: 360 N; cable #2: 360 N

• cable #1: 510 N; cable #2: 510 N

Tags

NGSS.HS-PS2-1

A skier slides down a frictionless hill with an acceleration of 2.04 m/s2. What angle does the hill make with the horizontal?

• 78.0°

• 30.0°

• 12.0°

• 6.0°

Tags

NGSS.HS-PS2-1

A child wearing a slippery snowsuit is sitting on a sled such that the coefficient of static friction between the suit and the sled is 0.112. What is the maximum acceleration possible for the sled before the child slips off?

• 9.80 m/s²

• 8.70 m/s²

• 1.10 m/s²

• 0 m/s²

Tags

NGSS.HS-PS2-1

You are riding on a “free-fall” ride at an amusement park. You hold a coin in front of you and let it go. What will the coin do?

• move upward relative you

• stay in front of you

• move downward relative to you

• move outward away from you

Tags

NGSS.HS-PS2-1

A road is banked such that cars can go around the curve even if it is icy and friction is essentially zero. What forces belong on a Free Body Diagram for a car under these conditions?

• gravity, normal

• gravity only

• normal only

• gravity, normal, centripetal

What is a force that works AGAINST MOTION?

• Force
• Motion
• Gravity
• Friction

Why does a rolling ball stop?

• Gravity
• Friction
• Waterfalls
• Sand

Tags

NGSS.MS-PS2-2

NGSS.MS-PS3-5

In a game of tug of war, one dog is pulling with a force of 10N north and another dog is pulling with 5N south.  What is the net force?

• 5N north
• 15N north
• 50N north
• 5N south

Tags

NGSS.HS-PS2-1

Frictional force between two surfaces depends on which of the following?

I. speed of the objects rubbing together

II. surface area of the objects

III. materials the surfaces are made of

• I and II

• I and III

• I, II and III

• III only