7. Go The table that follows lists four pairs of initial and final angular ve- locities for a rotating fan blade. The elapsed time for each of the four pairs of angular velocities is 4.0 s. For each of the four pairs, find the average angular acceleration (magnitude and direction as given by the algebraic sign of your answer). Initial angular velocity w Final angular velocity w (a) +2.0 rad/s +5.0 rad/s (b) +5.0 rad/s +2.0 rad/s (c) -7.0 rad/s -3.0 rad/s (d) +4.0 rad/s -4.0 rad/s

7. Go The table that follows lists four pairs of initial and final angular ve- locities for a rotating fan blade. The elapsed time for each of the four pairs of angular velocities is 4.0 s. For each of the four pairs, find the average angular acceleration (magnitude and direction as given by the algebraic sign of your answer). Initial angular velocity w Final angular velocity w (a) +2.0 rad/s +5.0 rad/s (b) +5.0 rad/s +2.0 rad/s (c) -7.0 rad/s -3.0 rad/s (d) +4.0 rad/s -4.0 rad/s

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter3: Motion In Two Dimensions

Section: Chapter Questions

Problem 30P: A point on a rotating turntable 20.0 cm from the center accelerates from rest to a final speed of...

See similar textbooks

Similar questions

Keratinocytes are the most common cells in the skins outer layer. As these approximately circular cells migrate across a wound during the healing process, they roll in a way that reduces the frictional forces impeding their motion. (a) Given a cell body diameter of 1.00 105 m (10 m), what minimum angular speed would be required to produce the observed linear speed of 1.67 107 m/s (10 m/min)? (b) How many complete revolutions would be required for the cell to roll a distance of 5.00 103 m? (Because of slipping as the cells roll, averages of observed angular speeds and the number of complete revolutions are about three times these minimum values.)
An ice skater is preparing for a jump with turns and has his arms extended. His moment of inertia is 1.8kgm2 while his arms are extended, and he is spinning at 0.5 rev/s. If he launches himself into the air at 9.0 m/s at an angle of 45 with respect to the ice, how many revolutions can he execute while airborne if his moment of inertia in the air is 0.5kgm2 ?
What is the value of the angular acceleration of the second hand of the clock on the wall?
A bicycle tire is spinning clockwise at 2.50 rad/s. During a time period t = 1.25 s, the tire is slopped and spun in the opposite (counterclockwise) direction, also at 2.50 rad/s. (Calculate (a) the change in the tires angular velocity and (b) the tire's average angular acceleration av.
Jeff, running outside to play, pushes on a swinging door, causing its motion to be briefly described by = t2 + 0.800 t + 2.00,where t is in seconds and is in radians. At t = 0 and at t = 1.50s, what are the a. angular position, b. angular speed, and c. angularacceleration of the door?
A digital audio compact disc carries data, each bit of which occupies 0.6 m along a continuous spiral track from the inner circumference of the disc to the outside edge. A CD player turns the disc to carry the track counterclockwise above a lens at a constant speed of 1.30 m/s. Find the required angular speed (a) at the beginning of the recording, where the spiral has a radius of 2.30 cm, and (b) at the end of the recording, where the spiral has a radius of 5.80 cm. (c) A full-length recording lasts for 74 min 33 s. Find the average angular acceleration of the disc. (d) Assuming that the acceleration is constant, find the total angular displacement of the disc as it plays. (e) Find the total length of the track.
Olympic ice skaters are able to spin at about 5 rev/s. (a) What is their angular velocity in radians per second? (b) What is the centripetal acceleration of the skater's nose if it is 0.120 m from the axis of rotation? (c) An exceptional skater named Dick Button was able to spin much faster in the 1950s than anyone since—at about 9 rev/s. What was the centripetal acceleration of the tip of his nose, assuming it is at 0.120 m radius? (d) Comment on the magnitudes of the accelerations found. It is reputed that Button ruptured small blood vessels during his spins.
The tub of a washer goes into its spin cycle, starting from rest and gaining angular speed steadily for 8.00 s, at which time it is turning at 5.00 rev/s. At this point, the person doing the laundry opens the lid, and a safety switch turns off the washer. The tub smoothly slows to rest in 12.0 s. Through how many revolutions does the tub turn while it is in motion?
In circular motion, a tangential acceleration can change the magnitude of the velocity but not its direction. Explain your answer.
The dung beetle is known as one of the strongest animals for its size, often forming balls of dung up to 10 times their own mass and rolling them to locations where they can be buried and stored as food. A typical dung ball formed by the species K. nigroaeneus has a radius of 2.00 cm and is rolled by the beetle at 6.25 cm/s. (a) What is the rolling balls angular speed? (b) How many full rotations are required if the beetle rolls the ball a distance of 1.00 m?
A centrifuge in a forensic investigation laboratory rotates at an angular speed of 3,650 rev/min, clockwise (when viewed from above). When switched off, it rotates through 48.0 revolutions before coming to rest. Assuming it is constant, what is the magnitude of angular acceleration (in rad/s2)?
Can an object have zero translational acceleration and, at thesame time, have nonzero angular acceleration? If your answeris no, explain why not. If your answer is yes, give a specificexample.