Question

The four tyres of an automobile are inflated to a pressure of $2.0\times {10}^5$Pa. Each Tyre has an area of $0.024m^2$ in contact with the ground. Determine the weight of the automobile.

• A. $1.92\times {10}^4$N
• B. $1.92\times {10}^5$N
• C. $1.92\times {10}^6$N
• D. $2.92\times {10}^4$N

Answer 1

The correct option is A $1.92\times {10}^4$N

Given, pressure, $P=2.0\times {10}^5$;
area of tyre, $A=0.024m^2$;
weight of automobile, W=?
Since, automobile is supported by four tyres, load or force (F) on each tyre is one fourth of the weight of the automobile, i.e., F = W/4
Pressure, $P=\frac{F}{A}$
or $P=\frac{\left(W/4\right)}{A}=\frac{W}{4A}$
$W=4AP=4\times 0.024\times 2\times {10}^5=1.92\times {10}^{4}N$.
Hence, the weight of the automobile is $=1.92\times {10}^4$.