Question

A point on the circumference of a stone with a radius of 20 cm has a speed of 100 cm/s, the brakes are applied, but it takes 2 seconds to stop, its angular acceleration is:

A. 7
B. 3
C. 10
D. 2.5

Answer 1

The angular acceleration of the stone is -50 cm/s².

Step-by-step explanation:

The angular acceleration can be calculated using the formula:

\alpha = \frac{{v_f - v_i}}{{t}}

where \(\alpha\) is the angular acceleration, \(v_f\) is the final speed, \(v_i\) is the initial speed, and \(t\) is the time taken to stop. In this case, the final speed \(v_f\) is 0 cm/s, the initial speed \(v_i\) is 100 cm/s, and the time \(t\) is 2 seconds. Substituting these values into the formula, we get:

\alpha = \frac{{0 - 100}}{{2}} = -50 \, \text{cm/s²}