Question

Find the angle in radian through which a pendulum swings, if its length is 75 cm and the tip describes an arc of length

(i) 10 cm

(ii) 21 cm

Answer 1

(i) Length of pendulum ( r ) = 75 cm

Length of arc ( l ) = 10 cm

Let pendulum makes an angle θ

Hence, angle make by swings pendulum = 2/15 radian

(ii) Length of pendulum ( r ) = 75 cm

length of arc ( l ) = 21 cm

Let pendulum makes an angle θ

θ = l/r = 21/5 = 7/25 radian

Hence, angle makes by swings pendulum
= 7/25