Question

The time of 25 oscillations of a simple pendulum is measured to be $50.0s$ by a watch of least count $0.1s$. The percentage error in time is

• A. $0.2\%$
• B. $0.02\%$
• C. $0.002\%$
• D. $2\%$

Answer 1

Answer: (A)

$0.2\%$

$\begin{array}{c}\text{Given-}\text{Time of}25\text{oscillations}=50.0s\\ \text{Least count of the watch}=0.1s\\ \text{Percentage error in Time}\\ \text{\%err}=\frac{\Delta T}{T}=\frac{0.1}{50}=\frac{0.1}{50}\times 100\%=0.2\%\\ \text{\% error in Time is}0.2\%\end{array}$