Question

Find the maximum percentage error in the measurement of pressure, if maximum errors in the measurement of force and length of a square plate are $3$% and $2$% respectively.

• A. $3$%
• B. $5$%
• C. $6$%
• D. $7$%

Answer 1

The correct option is D $7$%

$\text{P = pressure}=\frac{\text{force}}{\text{area}}=\frac{F}{l^2}$

$\Rightarrow \frac{△P}{P}\times 100\text{\%}=\frac{△F}{F}\times 100\text{\%}+2\frac{△l}{l}\times 100\text{\%}$
$=3$ % $+2$ ($2$% )$=7$ %