An electric iron of resistance `20Omega` takes a current of 5A. Calculate the heat developed in 30s.

An electric heater of resistance 8Omega draws 15A from the service mains in 2hours. Calculate the rate at which heat is developed in the heater.

An electric lamp of 100Omega , a toaster of resistance 50Omega , and a water filter of resistance 500Omega are connected in parallel to a 200V source. What is the resistance of an electric iron connected to the same source that takes as much current as all three appliances, and what is the current through it?

An AC source of emf E=200sin(100 pit) is connected across an inductor having resistance 100Omega and self inductance 2H. Calculate-Peak value of current flowing through the circuit.

battery gives a current of 0.5A with an external resistor of 12 Omega and.0.25A with resistor of 25 Omega Calculate the internal resistance of the battery.

A change of 0.2 mA in the base current causes a 5 mA in the the collector current of common emitter amplifier. ii) If the input resistance is 2KΩ and its voltage gain is 75, calculate the load resistance used in the circuit.