Advertisements
Advertisements
Question
How does the heat produced by die passage of current in a metallic wire depend on the current in the wire?
Advertisements
Solution
The heat produced is proportional to the square of current passed in the wire.
RELATED QUESTIONS
State and define the household unit of electricity.
An electric kettle is rated 2.5 kW, 250 V. Find the cost of running the kettle for two hours at Rs. 5.40 per unit.
The electric bulbs used these days have a coil-coiled filament. State its reason.
What changes in energy occur in an electric heater?
Two lamps are rated 220V, 50W and the other rated 220V, 100W are connected in series with the mains of 220 V. Explain, why the 50W lamp glows more?
Name a metal that is used as an electron emitter. Give one reason for using this metal.
How is the amount of heat produced calculated due to the passage of current in a metallic conductor? Derive an expression for it.
Two resistances R1 = 4Ω and R2 = 6Ω are connected in series. The combination is connected with a battery of e.m.f. 6V and negligible resistance. Calculate:
(i) the heat produced per minute in each resistor,
(ii) the power supplied by the battery.
A battery of e.m.f. 12V and internal resistance 1.6 Ω is connected to two resistors of 4Ω and 6Ω connected in parallel. Calculate:
(i) the current drawn from the battery,
(ii) the power dissipated in each resistor,
(ii)the total power supplied by the battery.
1 kWh is equal to:
