An ideal frictionless dc permanent magnet motor operating from a 24 v source has a no load speed of 240 radians/sec and an armature resistance of 0.2 ohms. compute the stall torque of the motor in newton-meters.

Estimate the change in specific internal energy au and specific enthalpy h from inlet to outlet for ethylene glycol (a liquid) flowing through each of the following devices: (a) a heat exchanger where the glycol temperature increases from 20 °c to 80 °c; (b) a pump operating at about 25 °c and increasing the glycol pressure from 100 kpa to 8 mpa.