Question

A series circuit consists of a battery of negligibleinternalresistance, a variable resistor, and an electric motorofnegligible resistance. The current in the circuit is 2 amperes(A)when the resistance in the circuit is adjusted to 10ohms(Ω). Underthese conditions the motor lifts a 1-kilogrammass vertically at aconstant speed of 2 meters per second(m/s).

(a) Determine the electrical power that is

i. dissipated in the resistor

ii. used by the motor in liftingthemass

iii. supplied by the battery

(b) Determine the potential difference across

i. the resistor

ii. the motor

iii. the battery

The resistor is now adjusted until the mass rises verticallyata constant speed of 3 meters per second (m/s). The voltagedropacross the motor is proportional to the speed of the motor, andthecurrent remains constant.

(c) Determine the voltage drop across the motor

(d) Determine the new resistance in the circuit