Advertisements
Advertisements
Question
Name the factors on which the heat produced in a wire depends when current is passed in it, and state how does it depend on the factors stated by you.
Advertisements
Solution
Factors on which heat produced depends:
- On the current of wire: The square of the current l flowing through the wire is directly proportional to the heat H produced by the wire, i.e. H ∝ I2.
- On the resistance of wire: The wire's resistance, R, is directly proportional to the heat, H, that it generates. i.e. H ∝ R.
- On time: The quantity of heat H generated in the wire is proportionate to the duration t. during which current flows through it. i.e. H ∝ t.
From the above, H ∝ I2Rt or H =0.24 I2Rt.
APPEARS IN
RELATED QUESTIONS
An electric room heater draws a current of 2.4 A from the 120 V supply line. What current will this room heater draw when connected to 240 V supply line?
An electric iron of 1100 W is operated for 2 hrs daily. What will be the electrical consumption expenses for that in the month of April? (The electric company charges Rs 5 per unit of energy).
A coil of an alloy _______ is used in electric heater cooker as a resistor.
What is a short circuit?
Heating effect of current is called ______
An electric kettle consumes 1 kW of electric power when operated at 220 V. A fuse wire of what rating must be used for it?
Can we use the same fuse in a geyser and a television set? Explain.
An MCB can be used instead of a fuse in an electrical circuit.
An electric fuse has a body made of ceramic and two points for connecting the fuse wire.
A student boils water in an electric kettle for 20 minutes. Using the same mains supply he wants to reduce the boiling time of water. To do so should he increase or decrease the length of the heating element? Justify your answer.
