The percentage error in the measurement of a physical quantity $m$ given by $m = \pi \tan \theta$ is minimum when $\theta = \dots \dots \dots \dots \dots ^\circ$ (Assume that the error in $\theta$ remains constant).

The length of a rod is measured by a meter scale having a least count of $0.1 \text{ cm}$ and the diameter is measured by vernier callipers having a least count of $0.01 \text{ cm}$. The length of the rod is $5.0 \text{ cm}$ and the radius is $2.0 \text{ cm}$. The percentage error in the calculated value of the volume is: (in $\%$)

The period of oscillation of a simple pendulum is given by $T = 2\pi\sqrt{\frac{l}{g}}$ where $l$ is about $80\text{ cm}$ and is known to have $0.1\text{ cm}$ accuracy. The period is about $1.5\text{ s}$. The time of $50$ oscillations is measured by a stop watch of least count $0.1\text{ s}$. The percentage error in $g$ is nearly

The mass of the body is $10.000\,g$ and its volume is $10.00\,cm^3$. If the measured values are expressed up to the correct significant figures,the maximum error in the measurement of density is

The maximum error in the measurement of the density and mass of the uniform cube are $8\%$ and $2\%$ respectively. Hence, the maximum error in the measurement of length will be (in $\%$)

Zero error in an instrument introduces