The period of oscillation of a simple pendulum of length $l$ is about 0.5 sec . The time of 100 osci

Question

The period of oscillation of a simple pendulum of length $l$ is about 0.5 sec . The time of 100 oscillations has been measured with a stop watch of 1 sec resolution. The length $l$ is 10 cm measured with the accuracy of 1 mm . Then the percentage error in the $g$ measurement is

Professor PC Thomas Classes · Answer

$\frac{\Delta g}{g} = \frac{\Delta l}{l} + 2\frac{\Delta T}{T} = \frac{0.1}{10} + 2(\frac{1}{100}) = 3\%$.