Question

When gasoline is burned in the cylinder of an engine, it creates a high pressure that pushes the piston. If the pressure is 100.0 psi and it moves a 3.0 in diameter piston a distance of 5.0 cm in 0.10 seconds, how much horsepower does this action produce?

Answer 1

Answer:

$\dot W=2.1074\ hp$

Explanation:

Given:

• pressure on the piston, $P=100\ psi=689476\ Pa$

• diameter of the piston, $d=3\ in=0.0762\ m$

• displacement of the piston, $s=0.05\ m$

• time taken in the piston displacement, $t=0.1\ s$

Now, we find the force on the piston:

$F=P.A$

where, A = area upon which pressure acts

$A=\pi.\frac{d^2}{4}$

$A=\pi.\frac{0.0762^2}{4}$

$A=0.00456\ m^2$

$\therefore F=689476\times 0.00456$

$F=3144.2638\ N$

we know that Power is given as:

$\dot W=\frac{F.s}{t}$

$\dot W=\frac{3144.2638\times 0.05}{0.1}$

$\dot W=1572.1319\ W$

$\dot W=2.1074\ hp$