Question

A particle starts rotating from rest. Its angular dispalcement is expressed by the following equation $\theta =0.025t^2-0.1t$ where $\theta$ is in radian and $t$ is seconds. The angular acceleration of the particle is

• A. $0.5rad/{\sec }^2$ at the end of $10\sec$
• B. $0.3rad/{\sec }^2$ at the end of $2\sec$
• C. $0.5rad/{\sec }^2$ at the end of $1\sec$
• D. Constant $0.05rad/{\sec }^2$

Answer 1

The correct option is C $0.5rad/{\sec }^2$ at the end of $1\sec$

$\begin{array}{c}\alpha =\frac{dw}{dt}=\frac{d^2\varnothing }{d{t}^2}\\ \frac{d\varnothing }{dt}=2\times 0.025t-0.1\\ \frac{d^2\varnothing }{dt}=0.50\end{array}$