Question

If the length of a cylinder is measured to be $4.28\text{cm}$ with an error of $0.01\text{cm}$, then the percentage error in the measurement will be

• A. $0.4\%$
• B. $0.5\%$
• C. $0.2\%$
• D. $0.1\%$

Answer 1

The correct option is C $0.2\%$

Given,
$L=(4.28\pm 0.01)\text{cm}$
On comparing with $L=L_{mean}\pm \Delta L_{mean}$, we get,
$L_{mean}=4.28\text{cm}$ and $\Delta L_{mean}=0.01\text{cm}$
We know, percentage error,
$\delta a=\frac{\Delta L_{mean}}{L_{mean}}\times 100\%$
$\Rightarrow \delta a=\frac{0.01}{4.28}\times 100\%=0.2\%$