40. A train travels at a speed of 144 km/h. Its wheels per- fectly adhere to the rails (no sliding) and have a diame- ter d = 80 cm. How many turns do they do in one second, roughly? A. 8 B. 57 C. 32 D. 115 E. 16

When a fan is turned off, its angular speed decreases from 168 rpm to 64.0 rpm in 6.08 s.  A) what is the angukar acceleration of the fan? B) How fast the edges of the blades are moving (in m/s) at time 6.08 s, if they are 86.0 cm long?

Starting from rest, the two wheels of a mountain bike have both an angular acceleration of 4.0 rad/s^2. How long does it take to make 10 revolutions?     A. 0.50 s.   B. 0.71 s.   C. 2.2 s.   D. 2.8 s.   E. 5.6 s

2. A safety device brings the blade of a power mower from an initial angular speed of wi to rest in 1.00 revolution. At the same constant acceleration, how many revolutions would it take the blade to come to rest from an initial angular speed that was three times as great, V3 = 3v1?

7. How many rpm would a Ferris wheel need to make for a person to feel weightless at the top of the rideif the wheel has a diameter of 16.5m?

6. A centrifuge in a lab rotates at an angular speed of 6500 rev/min. When switched off it rotates through 60 revolutions before coming to a rest. Find the constant angular acceleration of the centrifuge in rad/s².

B. F. 2.480 cm C. 1.682 cm 1--1 IZKUK A grinding wheel 1.40 m in diameter rotates with angular speed 1340 rpm. What is the linear speed of a point on the edge of the grinding wheel? 13. A. 98.23 m/s D. 111.6 m/s B. 106.5 m/s E. 77.27 m/s 91.90 m/s C. 81.76 m/s F. 1--1 [carpet-3] IZKUO An object at the end of a 0.95 m string swings around in a circl

5. A hoop of radius 0.24 m and a mass of 0.50 kg is released from rest and allowed to roll down an inclined is the translational speed (v) of the hoop after dropping a vertical distance of 2.60 m? m/s MOJS 60 ss? ssfól s 60 ssfo What

The driver of a car traveling at 17.7 m/s ap- plies the brakes and undergoes a constant deceleration of 1.38 m/s How many revolutions does each tire make before the car comes to a stop, assuming that the car does not skid and that the tires have radii of 0.42 m? Answer in units of rev. 2 ².