The least count of a stop watch is (1/5) s. The time of 20 oscillations of a pendulum is measured to be 25 s. What is the maximum percentage error in this measurement?

Question

The least count of a stop watch is (1/5) s. The time of 20 oscillations of a pendulum is measured to be 25 s. What is the maximum percentage error in this measurement? (A) 8 % (B) 1 % (C) 0.8 % (D) 16 %

Tardigrade Admin · Accepted Answer

Error in measuring 25 sec =(1/5) The percentage error =(1/5) × (100/25) =0.8 %

Q. The least count of a stop watch is $\frac{1}{5} s$ . The time of $20$ oscillations of a pendulum is measured to be $25 s$ . What is the maximum percentage error in this measurement?

$8%$

$1%$

$0.8%$

$16%$

Error in measuring $25 sec = \frac{1}{5}$
The percentage error $= \frac{1}{5} \times \frac{100}{25}$
$= 0.8%$

Q. The least count of a stop watch is 51​s. The time of 20 oscillations of a pendulum is measured to be 25s. What is the maximum percentage error in this measurement?

8%

1%

0.8%

16%