A spinning disk is rotating at a rate of 4 rad/s in the clockwise direction as shown in the figure. What is the direction of the angular velocity vector? up left right down Submit Answer Tries 0/2 If the disk is slowing down at a rate of 2 rad/s2, what is the direction of the angular acceleration vector? right left down up Submit Answer Tries 0/2 Find the wheel's angular velocity after 4 s. rad/s Submit Answer Tries 0/2 Find the angle through which the wheel has turned after 4 s in radians. radians Submit Answer Tries 0/2

A spinning disk is rotating at a rate of 4 rad/s in the clockwise direction as shown in the figure. What is the direction of the angular velocity vector? up left right down Submit Answer Tries 0/2 If the disk is slowing down at a rate of 2 rad/s2, what is the direction of the angular acceleration vector? right left down up Submit Answer Tries 0/2 Find the wheel's angular velocity after 4 s. rad/s Submit Answer Tries 0/2 Find the angle through which the wheel has turned after 4 s in radians. radians Submit Answer Tries 0/2

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter12: Rotation I: Kinematics And Dynamics

Section: Chapter Questions

Problem 60PQ

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Similar questions

A wheel is rotating about a fixed axis with constant angular acceleration 3 rad/s2. At different moments, its angular speed is 2 rad/s, 0. and +2 rad/s. For a point on the rim of the wheel, consider at these moments the magnitude of the tangential component of acceleration and the magnitude of the radial component of acceleration. Rank the following five items from largest to smallest: (a) |at| when = 2 rad/s, (b)|ar| when = 2 rad/s, (c)|ar| when = 0, (d) |at| when = 2 rad/s, and (e) |ar| when = 2 rad/s. If two items are equal, show them as equal in your ranking. If a quantity is equal to zero, show that fact in your ranking.
A gymnast does cartwheels along the floor and then launches herself into the air and executes several flips in a tuck while she is airborne. If her moment of inertia when executing the cartwheels is 13.5kgm2 and her spin rate is 0.5 rev/s, how many revolutions does she do in the air if her moment of inertia in the tuck is 3.4kgm2 and she has 2.0 s to do the flips in the air?
A baseball catcher extends his arm straight up to catch a fast ball with a speed of 40 m/s. The baseball is 0.145 kg and the catcher’s arm length is 0.5 m and mass 4.0 kg. (a) What is the angular velocity of the arm immediately after catching the ball as measured from the arm socket? (b) What is the torque applied if the catcher stops the rotation of his arm 0.3 s after catching the ball?
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.
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A small ball of mass 0.50 kg is attached by a massless sting to a vertical rod that Is spinning as shown below. When the rod has an angular velocity of 6.0 rad/s, the sting makes an angle of 30 with respect to the vertical. (a) If the angular velocity is increased to 10.0 rad/s, what is the new angle of the string? (b) Calculate the initial and final angular momenta of the ball. (c) Can the rod spin fast enough so that the ball is horizontal?
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 ?
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