circular motion

An object is moving in a circular path. If the centripetal force is suddenly removed, how will the object move?

• It will move radially outward.

• b) It will move radially inward.

• c) It will move vertically downward.

• d) It will move in the direction in which its velocity vector points

  
  

  at the instant the centripetal force vanishes.

The latitude of Lubbock, Texas (known as the Hub City of the South Plains), is 33° N. What is its rotational speed, assuming the radius of the Earth at the Equator to be 6380 km?

• 464 m/s

• 0.464 m/s

• 389 m/s

• 253 m/s

9.6 In a conical pendulum, a bob moves in a horizontal circle, as shown in the figure. The period of the pendulum (the time it takes for the bob to perform a complete revolution) is

• T=2π√LcosƟ/g

• 2π√gcosƟ/L

• 2π√LsinƟ/g

• 2π√L/g

A ball attached to the end of a string is swung around in a circular path of radius r. If the radius is doubled and the linear speed is kept constant, the centripetal acceleration

• remains the same.

• increases by a factor of 4.

• decreases by a factor of 2.

• decreases by a factor of 4.

A point on a Blu-ray disc is a distance R/4 from the axis of rotation. How far from the axis of rotation is a second point that has, at any instant, a linear velocity twice that of the first point?

• R/16

• R/2

• R/8

• R

9.11 The figure shows a rider stuck to the wall without touching the floor in the Barrel of Fun at a carnival. Which diagram correctly shows the forces acting on the rider?

• 
• 
• 
• 

A bicycle’s wheels have a radius of 33.0 cm. The bicycle is traveling at a speed of 6.5 m/s. What is the angular speed of the front tire?

• 0.197 rad/s

• 19.7 rad/s

• 1.24 rad/s

• 215 rad/s

In a department store toy display, a small disk (disk 1)

of radius 0.100 m is driven by a motor and turns a larger disk

(disk 2) of radius 0.500 m. Disk 2, in turn, drives disk 3, whose radius is 1.00 m. The three disks are in contact, and there is no slipping. Disk 3 is observed to sweep through one complete revolution every 30.0 s.what is the angular speed of disk 3?

• 0.209 rad/s

• 0.405 rad/s

• 0.305 rad/s

• 0.260 rad/s

what is the ratio of the tangential velocities of the rims of three disks?

• 0.209m/s

• 0.309m/s

• 0.409m/s

• 0.509m/s

what is the angular speed of disk 1 and 2 ?

• w1=3.08 rad/s , w2=0.619 rad/s.

• w1=2.09 rad/s , w2=0.419 rad/s.

• w1=4.09 rad/s , w2=0.719 rad/s.

• w1=5.09 rad/s , w2=0.419 rad/s.