Question

if length of simple simple pendulum increases by 300% then calculate percentage change in its time period

Answer 1

Let length of simple pendulum is L , time period is T
We know, time period is given by T = 2π√(L/g) -----(1)

A/C to question,
Length of simple pendulum = L + 300% of L
= L + 300L/100
= L + 3L
= 4L
Time period , T' = 2π√(4L/g) = 2 × 2π√(L/g)
From equation (1), T' = 2T

% change in time period = (T' - T)/T × 100
= (2T - T)/T × 100
= 100%

Answer 2

%change =l+300l/100=4l=t2..

Therefore change will be of t2=4t1 ( by formula of T .2pirootl/g).