A stone tied to the end of a string 80 cm long is whirled in a horizontal circle with a constant speed. If the stone makes 14 revolutions in 25 s. What is the magnitude and direction of acceleration of the stone ?

Explanation

Here, `r = 80 cm = 0.8 m, v = 14//25s^(-1)`
`therefore omega = 2pi v`
`= 2 xx (22)/(7) xx (14)/(25) = (88)/(25) "rad s"^(-1)`
The centripetal acceleration, `a = omega^(2)r`
`= ((88)/(25))^(2) xx 0.80`
`= 9.90 m//s^(2)`
The directon of centripetal acceleration is along the string directed towards the centre of circular path.