In a simple pendulum experiment,the maximum percentage error in the measurement of length is $2\%$ and that in acceleration due to gravity $g$ is $4\%$. Then the maximum percentage error in determination of the time-period is

Explain the error of a sum or a difference.

If the length of rod $A$ is $3.25 \pm 0.01 \,cm$ and that of rod $B$ is $4.19 \pm 0.01 \,cm$,then the rod $B$ is longer than rod $A$ by:

$A$ physical quantity $X$ is related to four measurable quantities $a$,$b$,$c$,and $d$ as $X = a^2 b^3 c^{5/2} d^{-2}$. The percentage errors in the measurement of $a$,$b$,$c$,and $d$ are $1\%$,$2\%$,$3\%$,and $4\%$ respectively. The percentage error in the measurement of quantity $X$ is: (in $\%$)

The least count of a stopwatch is $0.2\, s$. The time for $20\, oscillations$ of a pendulum is measured to be $25\, s$. The percentage error in the measurement of time will be ........ $\%$

Four students measure the height of a tower. Each student uses a different method and each measures the height many different times. The data for each are plotted below. The measurement with the highest precision is