Exam 8: Rotational Kinematics

A fan rotating with an initial angular velocity of 1000 rev/min is switched off.In 2 seconds, the angular velocity decreases to 200 rev/min.Assuming the angular acceleration is constant, how many revolutions does the blade undergo during this time?

A grindstone of radius 4.0 m is initially spinning with an angular speed of 8.0 rad/s.The angular speed is then increased to 12 rad/s over the next 4.0 seconds.Assume that the angular acceleration is constant. -What is the magnitude of the angular acceleration of the grindstone?

A sculptor is sharpening a chisel on grindstone of radius 1.0 m that is spinning with a constant angular speed of 2.0 rad/s. -What is the tangential speed of a point on the rim of the grindstone?

A circular hula hoop rolls upright without slipping on a flat horizontal surface.Which one of the following statements is necessarily true?

A bicycle wheel of radius 0.70 m is rotating at an angular speed of 6.3 rad/s as it rolls on a horizontal surface without slipping.What is the linear speed of the wheel?

Which one of the following statements concerning a wheel undergoing rolling motion is true?

A spinning disc rotating at 130 rev/min slows and stops 31 s later.How many revolutions did the disc make during this time?

Complete the following statement: The angular measure 1.0 radian is equal to

The Earth takes slightly less than one day to complete one rotation about the axis passing through its poles.The actual time is 8.616 × 10⁴ s.Given this information, what is the angular speed of the Earth about its axis?

A wheel turns through an angle of 188 radians in 8.0 s; and its angular speed at the end of the period is 44 rad/s.If the angular acceleration is constant, what was the angular speed of the wheel at the beginning of the 8.0 s interval?

On an amusement park ride, passengers are seated in a horizontal circle of radius 7.5 m.The seats begin from rest and are uniformly accelerated for 21 seconds to a maximum rotational speed of 1.4 rad/s. -What is the tangential acceleration of the passengers during the first 21 s of the ride?

What is the angular speed in rad/s of the second hand of a watch?

During the time a compact disc (CD) accelerates from rest to a constant rotational speed of 477 rev/min, it rotates through an angular displacement of 0.250 rev.What is the angular acceleration of the CD?

A car is moving along a horizontal road at a constant velocity that is directed 45° south of east.What is the direction of the angular velocity of the wheels of the car?

Two motorcycles are riding around a circular track at the same angular velocity.One motorcycle is at a radius of 15 m; and the second is at a radius of 18 m.What is the ratio of their linear speeds, v₂^/v₁?

A 1.0-m roulette wheel reaches a maximum angular speed of 18 rad/s before it begins decelerating.After reaching this maximum angular speed, it turns through 35 revolutions (220 rad) before it stops.How long did it take the wheel to stop after reaching its maximum angular speed?

What is the tangential speed of Nairobi, Kenya, a city near the equator? The earth makes one revolution every 23.93 h and has an equatorial radius of 6380 km.

The original Ferris wheel had a radius of 38 m and completed a full revolution (2 $\pi$ radians) every two minutes when operating at its maximum speed.If the wheel were uniformly slowed from its maximum speed to a stop in 35 seconds, what would be the magnitude of the tangential acceleration at the outer rim of the wheel during its deceleration?

A bicycle with wheels of radius 0.4 m travels on a level road at a speed of 8 m/s.What is the angular speed of the wheels?

A 0.254-m diameter circular saw blade rotates at a constant angular speed of 117 rad/s.What is the tangential speed of the tip of a saw tooth at the edge of the blade?