Advertisements
Advertisements
प्रश्न
An electric kettle rated at 220 V, 2.2 kW, works for 3 hours. Find the energy consumed and the current drawn.
Advertisements
उत्तर
Given:
V = 220 V
P = 2.2 kW = 2.2 x 103 w
t = 3 h
Electrical energy, E = P x t
= 2.2 kW x 3 h
= 6.6 kWh
Current drawn, I = P/V
= `2.2x10^3/220`
= 10 A
APPEARS IN
संबंधित प्रश्न
An electric heater of resistance 8 Ω draws 15 A from the service mains 2 hours. Calculate the rate at which heat is developed in the heater.
When current is switched ‘on’ in a room heater, it ______.
Why is a series arrangement not used for connecting domestic electrical appliances in a circuit?
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?
Derive the expression for the heat produced due to a current 'I' flowing for a time interval 't' through a resistor 'R' having a potential difference 'V' across its ends. With which name is this relation known?
Name any six domestic appliances based on the heating effect of electric current.
Compute the heat generated while transferring 96000 coulombs of charge in two hours through a potential difference of 40 V.
Find the odd one out and give its explanation.
Explain the importance/uses of fuse wire.
What does overloading cause?
Name any two appliances which work under the principle of heating effect of current.
How does use of a fuse wire protect electrical appliances?
B1, B2 and B3 are three identical bulbs connected as shown in Figure. When all the three bulbs glow, a current of 3A is recorded by the ammeter A.
- What happens to the glow of the other two bulbs when the bulb B1 gets fused?
- What happens to the reading of A1, A2, A3 and A when the bulb B2 gets fused?
- How much power is dissipated in the circuit when all the three bulbs glow together?
An electric cell produces electricity from the ______ ______ in it.
Explain the working of an electric fuse.
What is a trip switch?
The following is not a safety device.
A fuse is used in an electric circuit to stop high currents flowing through the circuit.
Two students decided to investigate the effect of water and air on iron object under identical experimental conditions. They measured the mass of each object before placing it partially immersed in 10 ml of water. After a few days, the object were removed, dried and their masses were measured. The table shows their results.
| Student | Object | Mass of Object before Rusting in g |
Mass of the coated object in g |
| A | Nail | 3.0 | 3.15 |
| B | Thin plate | 6.0 | 6.33 |
What might be the reason for the varied observations of the two students?
An electric iron of resistance 20 Ω draws a current of 5 A. The heat developed in the iron in 30 seconds is ______.
