Question

The period of oscillation of a simple pendulum is T = 27
L
Measured value of L is 20.0 cm
g
known to 1 mm accuracy and time for 100 oscillations of the pendulum is found to be 90 s
using a wrist watch of 1 s resolution. What is the accuracy in the determination of g ?​

Answer 1

Correct option is

B

2.7%

Given, T=2π

g

L

Squaring on both sides and rearranging, g=4π

2

T

2

L

Now,

g

Δg

=

L

ΔL

+2

T

ΔT

g

Δg

=

0.2

10

−3

+

90

2×1

g

Δg

×100=

2

1

+

9

20

=2.7%