A 6 V-12 W lamp is connected in series with a source of 12 V supply. Calculate the value of the resistance R for the proper working of the lamp. What is the current flowing through the circuit?
Two coils of resistances 3 Ω and 6 Ω are connected in series across a battery of emf 12 V. find the electrical energy consumed in 1 minute in each resistance when these are connected in series.
Two bulbs A and B are rated 100 W-120 V and 10 W-120 V respectively. They are connected across a 120 V source in series. Which will consume more energy ?
An electric iron consumes energy at the rate of (a) 840 W when heating is at the maximum rate and (b) 360 W when the heating is at the minimum. The voltage is 220 V. what are the current and the resistance in each case?
An electric heater draws a current of 5 A and its element has a resistance of 50 Ω. If the heater is switched on for 5 minutes, calculate the energy released in kilojoules.
An electric room heater has a resistance of 25 Ω and operates at 220 V for 12 minutes. Calculate heat energy dissipated by it in kilojoules.
Calculate the total power of 5 fans if each of them draws a current of 0.8 A at a potential difference of 220 V.
An electric bulb of resistance 400 Ω, draws a current of 0.5 A. Calculate the power of the bulb and the potential difference at its ends.
A soldering rod iron draws an energy of 45000 J in 4 minutes when the current flowing through its element is 6 A. Calculate the resistance of its heating element.
An electric kettle is rated at 230 V, 1000 W. What is the resistance of its element ? What maximum current can pass through its element?
Two bulbs A and B are rated 100 W – 120 V and 10 W - 120 V respectively. They are connected in parallel across a 120 V source. Find the current in each bulb. Which bulb will consume more energy?
What does an electric circuit mean ?
Define the unit of current.
Calculate the number of electrons constituting one coulomb of charge.
