Question

The diameter of a flywheel is $1.2m$ and it makes 900 revolutions per minute. Calculate the acceleration at a point on its rim.

• A. $540{\pi }^{2}m/s^2$
• B. $324m/s^2$
• C. $360{\pi }^{2}m/s^2$
• D. $540m/s^2$

Answer 1

The correct option is B $324m/s^2$

$\begin{array}{c}w=\frac{900}{60}rex/\sec =15rex/\sec \Rightarrow 30\pi rad/\sec \\ a=w^{2}R={\left(30\pi \right)}^2\frac{6}{10}=900{\pi }^2\times \frac{3}{5}=540{\pi }^{2}rad/\sec \\ a_t=Ra=540\times \frac{6}{10}=324m/s^2\end{array}$