A 60 Hz 120/208V Y-connected source supplies a 600 ohm Y-connected load. Assign the zero angle to the phase a to neutral voltage. Draw the circuit and calculate the voltage across and current through each phase of the load, including phase angles for each voltage and current. Calculate the 3 line-line voltages at the load, including phase angles relative to the reference zero angle.

Abrake has a normal braking torque of 2.8 kip in and heat-dissipating cast-iron surfaces whose mass is 40 lbm. suppose a load is brought to rest in 8.0 s from an initial angular speed of 1600 rev/min using the normal braking torque; estimate the temperature rise of the heat dissipating surfaces.

What is the major difference between thermoplastics and thermosetting plastics from the polymerization structure point of view?

An inventor claims to have developed a reversed heat engine (ie. a heat pump) which is able to deliver 10 kj heat into the room at 20°c from outside ambient temperature of -10°c by consuming only 2 kj electricity in winter. this claim is a)-impossible b)-possible only if the heat pump is ideal c)-practically possible d)-unable to be assessed as it depends on the working fluid used in the heat pump.