Advertisements
Advertisements
Question
Write an expression for the amount of heat produced in a resistor when an electric current is passed through it stating the meanings of the symbols used.
Advertisements
Solution
When an electric current I passes through the conductor, the amount of heat produced in time t is:
H = VIt
Since, V = IR
So, H = I2Rt
APPEARS IN
RELATED QUESTIONS
How does the resistance of a wire vary with its area of cross-section?
The safety device based on the heating effect of electric current is called a ______.
Write down the formula for the heat produced when a current I is passed through a resistor R for time t.
An electric iron of resistance 20 ohms draws a current of 5 amperes. Calculate the heat produced in 30 seconds.
An electric fuse works on the:
(a) chemical effect of current
(b) magnetic effect of current
(c) lighting effect of current
(d) heating effect of current
An electric iron is connected to the mains power supply of 220 V. When the electric iron is adjusted at 'minimum heating' it consumes a power of 360 W but at 'maximum heating' it takes a power of 840 W. Calculate the current and resistance in each case.
Identify the figure and give its use.
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.
In the electric equipment producing heat like iron, electric heater, boiler, toaster etc., an alloy such as nichrome is used, not pure metals.
What is the heating effect of electric current?
