Question

In: Physics

QUESTION 1 A disk (radius 13.5 cm] rotates about a fixed axis through its center of...

QUESTION 1

A disk (radius 13.5 cm] rotates about a fixed axis through its center of mass and perpendicular to the disk. At t = 0 the disk is rotating at frequency 6.64 Hz, and it accelerates uniformly to frequency 27.6 Hz after spinning through 60.4 revolutions. Find the angular acceleration of the disk, in rad/s².

QUESTION 2

The wheel of a cart has radius 64.6 cm. How many revolutions will it make if the cart goes 6.45 km?

Expert Solution

Multiple questions posted, so answeing only the first question:

1. angular velocity is given by:=2f, where is angular velocity, f is frequency.

Initial frequency=6.64 Hz

So,initial angular velocity i= 2*6.64=41.72 rad/s.

Final frequency=27.6 Hz

So,final angular velocity f= 2*27.6=173.42 rad/s.

Angular displacement =60.4 revolutions=60.4*2=379.5 radians.

Now,in uniform acceleration, f2=i2+2, where f is final angular velocity,i is initial angular velocity, is angular acceleration, is angular displacement.

So,173.422=41.722+2*379.5

=>2*379.5=173.422-41.722=28333.938

=>=28333.938/(2*379.5)=37.33 rad/s2

genius_generous answered 3 days ago

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