Fuel supplied to an SI engine has a calorific value $42000$ kJ$/$kg$.$ The air fuel ratio is $15$:$1$

and mass flow rate of air is $0\mathrm{.}1$ kg$/$s$.$ The pressure in the cylinder at $30\%$ and $70\%$ of the

compression stroke are $1\mathrm{.}3$ bar and $2\mathrm{.}6$ bar respectively. Assuming that the compression

follows the law $1\mathrm{.}3=$ constant. Find the compression ratio. If the relative efficiency of

the engine compared with the air$-$standard efficiency is $50\%,$ find the power output

$($indicated power$).$Fuel supplied to an SI engine has a calorific value $42000k\frac{J}{k}g.$ The air fuel ratio is $15$:$1$

and mass flow rate of air is $0\mathrm{.}1k\frac{g}{s}.$ The pressure in the cylinder at $30\%$ and $70\%$ of the

compression stroke are $1\mathrm{.}3$ bar and $2\mathrm{.}6$ bar respectively. Assuming that the compression

follows the law $p{V}^{1\mathrm{.}3}=$ constant. Find the compression ratio. If the relative efficiency of

the engine compared with the air$-$standard efficiency is $50\%,$ find the power output

$($indicated power$).($Answers are: $4\mathrm{.}68,64\mathrm{.}4$ kW $)$