Question

what is the centripetal acceleration of an object(mass=50g) on the end of an 80 cm string rotating at the constant rate of 4 times a second

Answer 1

mass of object , m = 50g

length of string attached with object , l = 80cm = 0.8m

string - mass system is rotating at the constant rate of 4 times a second.

so, frequency , f = 4Hz or 4 cycle/sec

angular frequency, w= 2π × frequency

= 2π × 4 = 8π rad/s

velocity

now, centripetal acceleration = w²l

= (8π)² × 0.8

= 64 × π² × 0.8

= 504.8 m/s²

hence, centripetal acceleration is 504.8 m/s²