Question

The engine of a car develops a power of $5HP$ and force $500N$ while running a uniform speed S. Calculate the value of S.

Answer 1

Step 1: Given data,

Power = $5HP$

Force = $500N$

$1HP=750watts$

Step 2: To calculate speed

Formula used:$power=\frac{work}{time}$

$power=\frac{force\times displacement}{time}=force\times \frac{displacement}{time}$

$power=force\times velocity$

Step 3: To convert $HP$ into $watts$

$1HP=750watts$

$5HP=5\times 750watts$

$5HP=3750watts$

Step 4: Calculate the velocity,

$power=force\times velocity$

$3750=500\times velocity$

$velocity=\frac{3750}{500}$$=7.5\raisebox{1ex}{$m$}\!\left/ \!\raisebox{-1ex}{$s$}\right.$

The magnitude of velocity = speed = $7.5\raisebox{1ex}{$m$}\!\left/ \!\raisebox{-1ex}{$s$}\right.$

Therefore, the magnitude of velocity i.e. speed is $7.5\raisebox{1ex}{$m$}\!\left/ \!\raisebox{-1ex}{$s$}\right.$.