$7\mathrm{.}3$ A shunt$-$connected,$75-$kW$,250-$V dc motor has an armature resistance of$45$ mS$2$ and a field resistance of $1852.$ When operated at $250$ V$,$ its no$-$load

speed is $1850$ r$/$min$.$

a$.$ The motor is operating under load at a terminal voltage of $250$ V and aterminal current of $290$ A$.$ Calculate $($i$)$ the motor speed in r$/$min$.($ii$)$ theload power in kW$,$ and $($iii$)$ the load torque in N$.$m$.$