A disk rotates with constant angular acceleration. The initial angular speed of the disk is 2?...

A disk rotates with constant angular acceleration. The initial angular speed of the disk is 2? rad/s. After the disk rotates through 20? radians, the angular speed is 3? rad/s. (a) What is the magnitude of the angular acceleration? rad/s2 (b) How much time did it take for the disk to rotate through 20? radians? s (c) What is the tangential acceleration of a point located at a distance of 3 cm from the center of the disk? m/s2

Expert Solution

1.

i solve this problem before just plug the value you will get the answer

A disk rotates with constant angular acceleration. The initial angular speed of the disk is 2? rad/s. After th?

A disk rotates with constant angular acceleration. The initial angular speed of the disk is 2? rad/s. After th?

A disk rotates with constant angular acceleration. The initial angular speed of the disk is 2? rad/s. After the disk rotates through 18? radians, the angular speed is 9? rad/s.

(a) What is the magnitude of the angular acceleration?

(b) How much time did it take for the disk to rotate through 18? radians?

(c) What is the tangential acceleration of a point located at a distance of 4.4 cm from the center of the disk?

(a) v^2 - u^2 = 2a*s
so (9?)^2 - (2?)^2 = 2a*(18?)
so 81?^2 - 4?^2 = 36?*a
so a = 77?^2 / 36? = 77? / 36 rad/s^2 = (2.14)? rad/s^2 = 6.72 rad/s^2

(b) v = u + a*t
so 9? = 2? * (2.14)?*t
so t = (9? - 2?) / (2.14)? s
so t = 7? / (2.14)? s
so t = 3.27 s

(c) At a radius of 4.4cm = 0.044m, circumference = 2?*.044m = 0.276m = 2? radians
So tangential acceleration is (2.14)? rad/s^2 * 0.276m / 2? rad = 0.296 m/s^2

genius_generous answered 10 months ago

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