(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

An electric turntable 0.710 m in diameter is rotating about a fixed axis with an initial angular velocity of 0.230 rev/s. The angular acceleration is 0.887 rev/s^2.

A. Compute the angular velocity after a time of 0.192 s.

B. Through how many revolutions has the blade turned in this time interval?

C. What is the tangential speed of a point on the tip of the blade at time t = 0.192 s?

D. What is the magnitude of the resultant acceleration of a point on the tip of the blade at time t = 0.192 s?

2. Relevant equations

Any rotational kinematic.

Conversions to radians/revolutions

3. The attempt at a solution

A.) I took the angular velocity 0.230 and multiplied it by 2pi which equals 1.445 rad/s.

I then plugged it into a kinematic equation, 1.445+(0.887*0.230)^2 = 2.56 rad/s = .400 rad/s.

This is right.

B.) The I used the distance rotational kinematic equation, 1.445 * 0.230 +.5(0.887)(0.230)^2 = 0.3558 rad. = 0.57 rev.

This is wrong. Need help.

C) To to find the tangential speed, I did 0.710 m * 2.56 rad/s = 1.82.

This is wrong. Need help.

D) Need help.

Thanks.

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# Homework Help: Rotational kinematics of a turntable

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