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5 votes
A figure skater begins spinning counterclock-

wise at an angular speed of 4.6 7 rad/s. Dur-
ing a 4.2 s interval, she slowly pulls her arms
inward and finally spins at 7.3 7 rad/s.
What is her average angular acceleration
during this time interval?
Answer in units of rad/s.​

User BillyNate
by
5.0k points

1 Answer

11 votes

Answer:

Angular acceleration,
\alpha =0.64\ rad/s^2

Step-by-step explanation:

Given that,

Initial angular velocity,
\omega_i=4.67\ rad/s

The final angular velocity,
\omega_f=7.37\ rad/s

Time, t = 4.2 s

We need to find her average angular acceleration during this time interval. Acceleration is the rate of change of velocity. So,


\alpha =(\omega_f-\omega_i)/(t)\\\\\alpha =(7.37-4.67)/(4.2)\\\\\alpha =0.64\ rad/s^2

So, her average angular acceleration is
0.64\ rad/s^2.