The pressure on a circular plate is measured by measuring the force on the plate and the radius of the plate. If the errors in measurement of the force and the radius are 5% and 3% respectively, the percentage of error in the measurement of pressure is

Options

A. 8
B. 14
C. 11
D. 12

Answer

C

Explanation

The pressure exerted on the circular plate, `p=(F)/(A)=(F)/(piR^2)`
where, R=radius of circular disc, A=area of circular disc and F=Force on circular disc
Now, percentage error in pressure.
`(Deltap)/(p)xx100=(DeltaF)/(F)xx100+2(DeltaR)/(R)xx100`
`=5+2(3)=5+6=11Rightarrow(Deltap)/(p)xx100=11%`