one boy gets a seconds pendulum of length 100 cm . Seeing this , his friend wants to make his own seconds pendulum. But after making the pendulum, he finds that the pendulum has atime period 0f 1.4 sec. What is the length of the pendulum made by his friend?
we know that the time period of a simple pendulum is written as
T = 2π / √(l/g)
or
the length of the pendulum is
l = gT2 / 4Ï€2
now, here
T = 1.4 s
g = 10 m/s2
so,
l = [10 x (1.4)2] / (4 x 3.142)
or
l = 19.6 / 39.43
thus, length l =0.497 m