Vertical circles

A ball is fastened to a string and is swung in a vertical circle. When the ball is at the highest point of the circle its velocity and acceleration directions are:

• A

• B

• C

• D

A ball with a mass m is fastened to a string and is swung in a vertical circle. When the ball is at the highest point of the circle the tension in the string is:

• mg

• mg + ma

• ma -mg

• mg/ma

Tags

NGSS.HS-PS2-1

NGSS.HS-PS2-4

An object, shown in the accompanying figure, moves in uniform circular motion. Which arrow best depicts the net force acting on the object at the instant shown?

• a

• b

• c

• d

A motorcyclist moves at a constant speed down one hill and up another hill along the smooth curved surface. When the motorcyclist reaches the lowest point of the curve its velocity and acceleration directions are:

• a

• b

• c

• d

A car moves along the curved track. What is the apparent weight of the driver when the car reaches the lowest point of the curve?

• mg

• mg + ma

• ma –mg

• mg/ma

A car moves along the curved track. What is the direction of F_N of the driver when the car reaches the lowest point of the curve?

• Down

• Up

• Forward

• Backward

Tags

NGSS.HS-PS2-1

NGSS.HS-PS2-4

The horizontal table rotates at a constant speed. As viewed from above, a coin on the table moves counterclockwise in a circle. Which of the following vectors best represents the direction of the frictional force exerted on the coin by the table when the coin is in the position shown?

• a

• b

• c

• d

A centripetal force F is applied to an eraser moving at a constant speed v in a horizontal circle of radius r. If the same force is applied, but the radius is halved, what happens to the speed of the eraser?

• Increased by a factor of 2

• decreased by a factor of 2

• increased by a factor of √2

• decreased by a factor of √2

A centripetal force F is applied to an object moving at a constant speed v in a horizontal circle of radius r. If the radius is quadrupled and the speed is doubled, what happens to the centripetal force?

• Increased by a factor of 2

• decreased by a factor of 2

• doesn’t change

• increased by a factor of √2

Tags

NGSS.HS-PS2-1

Which car, at the moment of the snapshot, has the smallest displacement?

• a

• b

• c

• all have equal displacement