While measuring the acceleration due to gravity by a simple pendulum,a student makes a positive error of $1\%$ in the length of the pendulum and a negative error of $3\%$ in the value of time period. His percentage error in the measurement of $g$ by the relation $g = 4{\pi ^2}(l/T^2)$ will be ........ $\%$

Out of absolute error,relative error,and fractional error,which has a unit and which has no unit?

The period of an oscillating simple pendulum is $T = 2 \pi \sqrt{\frac{\ell}{g}}$,where the length $\ell = 100 \text{ cm}$ with an error of $1 \text{ mm}$. The period $T = 2 \text{ s}$. The time for $100$ oscillations is measured by a stopwatch with a least count of $0.1 \text{ s}$. The percentage error in the gravitational acceleration $g$ is: (in $\%$)

The length and width of a rectangular room are measured to be $3.95 \pm 0.05 \,m$ and $3.05 \pm 0.05 \,m$,respectively. The area of the floor is .................... $m^2$

The unit of percentage error is

The resistance of a wire is determined by measuring the current flowing through it and the voltage difference across its ends. If the percentage error in the measurement of current and voltage difference is $3\%$ each,what will be the percentage error in the resistance of the wire?