Advertisements
Advertisements
प्रश्न
An electric bulb is rated at 220 V, 100 W. What is its resistance?
Advertisements
उत्तर
Given V = 220 V and P = 100 W
We know that power, P = IV = V2 / R
R = V2 / P
R = `( 220xx220)/100`
R = 484 Î
APPEARS IN
संबंधित प्रश्न
At what frequency is AC supplied to residential houses?
What is meant by "electric power"?
How many joules are there in one kilowatt-hour?
When an electric lamp is connected to 12 V battery, it draws a current of 0.5 A. The power of the lamp is:
(a) 0.5 W
(b) 6 W
(c) 12 W
(d) 24 W
Name two gases which are filled in filament type electric light bulbs.
Electrical power p is given by the expression P = (Q × V) ÷ time. Express the power P in terms of current and resistance explaining the meaning of symbols used there in.
When a current I flows through a resistance R for time t, the electrical energy spent is given by:
(a) IRt (b) I²Rt (c) `IR^2t` (d) `I^2R ⁄t`
A bulb of 40 W is used for 12.5 h each day for 30 days. Calculate the electrical energy consumed.
What is the current I in the given circuit (Fig. )?
Why is heating coil wound in the form of a helix in electric stove?
What changes in energy occur in an electric bulb?
If the rating of an electric bulb is 100W – 230V, Explain its meaning.
Why is the electric power from the generating station transmitted at high voltage?
An electric kettle is rated 3kW, 250V. What should be the current capacity of the fuse with it?
Find the energy released by a current of 0.25 amperes flowing through a heater for 5 minutes. The p.d. is 230 V.
A bulb is connected to a battery of e.m.f. 6V and internal resistance 2Ω A steady current of 0.5A flows through the bulb. Calculate the resistance of the bulb.
1 kWh = ____________
Compare the power used in the 2 Ω resistor in each of the following circuits:
- a 6 V battery in series with 1 Ω and 2 Ω resistors
- a 4 V battery in parallel with 12 Ω and 2 Ω resistors.
