Question

Find the mass of the block that a $40hp$ engine can pull along a level road at $15m{s}^{-1}$ if the coefficient of friction between block and road is $0.015$.

• A. 2532 kg
• B. 1353 kg
• C. 3553 kg
• D. 4553 kg

Answer 1

The correct option is B 1353 kg

Given,

$P=40hp=29828W$

$v=15m/s$

$\mu =0.015$

$g=9.8m/s^2$

$Power=force\times velocity$

$P=Fv$

$F=\frac{P}{v}$

$F=\frac{29829}{15}=1988.5N$

$F=\mu mg$

$m=\frac{F}{\mu g}$

$m=\frac{1988.5}{0.015\times 9.8}$

$m=13527.4kg$

The mass of the block is $13527.4kg$.