Forces in Two-Dimensional Physics

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 FBD 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 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

Which statement is true of fictitious forces?

• They are found only in non-inertial frames of reference.

• They are found only in inertial frames of reference.

• They are caused by real factors such as gravity.

• They are real forces even if their causes are not apparent.

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? (ignore air resistance)

• move upward relative you

• stay in front of you

• move downward relative to you

• move outward away from you

Tags

NGSS.HS-PS2-1

NGSS.HS-PS2-4

A ball is tied to the end of a string and whirled around a table in a horizontal circle. If the speed is doubled, how does the centripetal acceleration change?

• the centripetal acceleration is unchanged

• the centripetal acceleration is doubled

• the centripetal acceleration is tripled

• the centripetal acceleration is quadrupled

Tags

NGSS.HS-PS2-1

An airplane with a mass of 800 kg is flying in a circle of radius 500 m at 50 m/s. What is the centripetal force required to keep the airplane flying in the circle?

• 50 N

• 80 N

• 4000 N

• 8000 N

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 FBD for a car under these conditions?

• gravity, normal

• gravity only

• normal only

• gravity, normal, centripetal

The top of a hill on a roller coaster has a circular shape with a radius of 25.0 m. A car going over the top makes the passengers feel weightless at the very top. How fast is the car going?

• 3.13 m/s

• 9.80 m/s

• 15.7 m/s

• 245 m/s

Tags

NGSS.HS-PS2-1

NGSS.HS-PS2-4