Heating Effect of Current
Heating Effect of Current: Overview
This topic covers concepts, such as Joule's Law of Heating, Application of Joule’s Heating Effect, Electric Heater, Fuse, Electric Power, Power Supplied by a Battery, Power Consumed by a Battery, Rating of Electric Bulb, etc.
Important Questions on Heating Effect of Current
For safety, the fuse wire used in the mains for household supply of electricity must be made of metal having

A wind generator provides power to a factory whose equipment operates at and . The factory is connected to a wind generator with cables of total resistance of .
It is suggested that a transformer be used to step up the voltage of the wind generator so that the step-down transformer near the factory would bring the voltage down from to .
Determine the power loss in the cables now.

A wind generator provides power to a factory whose equipment operates at and . The factory is connected to a wind generator with cables of total resistance of .
Calculate the efficiency of the transmission line.

A wind generator provides power to a factory whose equipment operates at and . The factory is connected to a wind generator with cables of total resistance of .
Calculate the voltage at wind generator.

A wind generator provides power to a factory whose equipment operates at and . The factory is connected to a wind generator with cables of total resistance of .
Calculate the power lost in the cables.

From below which one is the equation for Joule's law of heating effect of electricity ?

An electric iron of Power is connected to a Mains. The current drawn by the iron is nearly.

In a large building, there are bulbs of , bulbs of , fans of and heater of are connected. The voltage of electric mains is . The minimum capacity of the main fuse of the building will be

In India electricity is supplied for domestic use at . It is supplied at in USA. If the resistance of a bulb for use in India is , the resistance of a bulb for use in USA will be

A wire connected to a power supply of V has power dissipation P1. Suppose the wire is cut into two equal pieces and connected parallel to the same power supply. In this case power dissipation is P2. The ratio is

A toaster operating at has a resistance of . The power is

Two heating wires of equal length are first connected in series and then in parallel. If the combinations are separately connected across the same time. The ratio of heat produced in the first case to that on the second is.

Of the two bulbs used in a house one glows more brightly than the other. Then which of the following statements is true ?

An electric iron of Power is connected to a Mains. The current drawn by the iron is nearly.

Three equal resistors connected in series with a source of emf to-gather dissipate of power. The power dissipated by these resistors connected in parallel will be

The power consumed by a simple circuit having total resistance is . If the resistance is reduced by half, the power consumed will be

An electric iron of Power is connected to a Mains. The current drawn by the iron is nearly.

Read the given passage and answer the following question:
The home electrical connection consists of 'live', 'neutral' and 'earth' wires. The 'live' and the 'neutral' wires have potential difference of . The 'earth' is connected to ground. Due to a fault in the equipment or if the plastic coating on the 'live' and the 'neutral' wires give a path for the two wires to come in contact with each other and a large current flows through it producing heat. If any inflammable material (such as wood, cloth, plastic, etc.) exists around that place it can catch fire. Therefore, a fuse wire is used as a precautionary measure.
From the below choose the name of the wire that is used to limit the current in an electric circuit by melting due to overheating when excessive current passes through it.

If the cell of emf shown in the figure, gives a power of , then, find the power consumed by the resistors and .

An electric motor operating on a supply draws a current of . If the efficiency of the motor is , then estimate the resistance of the winding of the motor.
