Open Question
A ceiling fan with 80-cm-diameter blades is turning at 60 rpm. Suppose the fan coasts to a stop 25 s after being turned off. (b) Through how many revolutions does the fan turn while stopping?
12. Rotational Kinematics
Equations of Rotational Motion
Back12. Rotational Kinematics
Equations of Rotational Motion
- Open QuestionA ceiling fan with 80-cm-diameter blades is turning at 60 rpm. Suppose the fan coasts to a stop 25 s after being turned off. (a) What is the speed of the tip of a blade 10 s after the fan is turned off?
- Open QuestionThe 2.0 kg, 30-cm-diameter disk in FIGURE P12.65 is spinning at 300 rpm. How much friction force must the brake apply to the rim to bring the disk to a halt in 3.0 s?
- Open Question
(I) Pilots can be tested for the stresses of flying high-speed jets in a whirling “human centrifuge,” which takes 1.0 min to turn through 26 complete revolutions before reaching its final speed.
(b) what was its final angular speed in rpm?
- Open Question
(II) A cooling fan is turned off when it is running at 780 rev/min . It turns 1250 revolutions before it comes to a stop.
(b) How long did it take the fan to come to a complete stop?
- Open Question
(II) Calculate the average angular velocity of a clock’s second hand, its minute hand, and its hour hand. State in rad/s .
(d) What is the average angular acceleration in each case?
- Open Question
(II) Calculate the angular velocity of the Earth (a) in its orbit around the Sun, and (b) about its axis.