Advertisements
Advertisements
प्रश्न
A heating coil has a resistance of 200 Ω. At what rate will heat be produced in it when a current of 2.5 A flows through it?
Advertisements
उत्तर
I = 2.5 A
R = 200 Ω
Rate of heat produced = Power = I2R = (2.5)2(200) = 1250 J/s
APPEARS IN
संबंधित प्रश्न
How does the resistance of a wire vary with its area of cross-section?
Why are the coils of electric irons and electric toasters made of an alloy rather than a pure metal?
Why does the connecting cord of an electric heater not glow hot while the heating element does?
An electric iron of resistance 20 ohms draws a current of 5 amperes. Calculate the heat produced in 30 seconds.
The current passing through a room heater has been halved. What will happen to the heat produced by it?
Which electric heating device in your home do you think have resistors which control the flow of electricity?
Give a scientific reason:
For electric power transmission, copper or aluminium wire is used.
Identify the figure and give its use.
Statement 1 : Electric current ( flow of electrons ) creates heat in the resistor.
Statement 2 : Heat in the resistor is created according to the rule of energy conservation.
Explain Statement 1 with the help of Statement 2.
Which of the following is correct?
An electric iron consumes energy at the rate of 420 W when heating is at the maximum rate and 180 W when heating is at the minimum rate. The applied voltage is 220 V. What is the current in each case?
An electric iron draws a current of 4 A when connected to 220 V mains. Its resistance must be:
Assertion: Bending of wire decreases the resistance of the electric wire.
Reason: The resistance of a conductor depends on length, thickness, nature of material and temperature of the conductor.
How does use of a fuse wire protect electrical appliances?
An electric fuse has a body made of ceramic and two points for connecting the fuse wire.
What are the factors affecting heating effect of electric current?
It would cost a man Rs. 3.50 to buy 1.0 kW h of electrical energy from the Main Electricity Board. His generator has a maximum power of 2.0 kW. The generator produces energy at this maximum power for 3 hours. Calculate how much it would cost to buy the same amount of energy from the Main Electricity Board.
Match the following
| 1. | Bulb | a. | Conductor |
| 2. | Electroplating | b. |
Insulator |
| 3. | Pure water | c. | Heating effect of current |
| 4. | Salt solution | d. | Chemical effect of current |
Name a few appliances which work on the basis of the heating effect of current.
Define the following:
Electrolyte
