Question

If the length and time period of an oscillating pendulum have errors of 1% and 3% respectively then the error in measurement of acceleration due to gravity is
a) 4%
b) 5%
c) 6%
d) 7%

Answer 1

We know,
Time period , T = 2π√(l/g)
Taking square both sides,
T² = 4π²l/g ⇒g = 4π²l/T²
So, for finding error in accelerating due to gravity we have to take formula,
% error in g = % error in l + 2 × % error in T

Given,
% error in l = 1 %
% error in T = 3 %
∴ % error in g = 1 % + 2 × 3 % = 7 %

Hence, option (d) is correct

Answer 2

Answer:

Answer = d) 7%

Explanation:

Answer is correct.