Advertisements
Advertisements
प्रश्न
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.
Advertisements
उत्तर
Given: E = 6V, r = 2Ω, i = 0.5A, t = 10 minute = 10 × 60s = 600s.
Let the resistance of bulb is R. Then i =`"E"/("R + r")`
or `0.5 = 6/("R" + 2)` or 0.5 (E + 2) = 6
or 0.5 R + 1 = 6 or 0.5 R = 6 - 1 = 5
or R = `5/0.5 = 10 Omega`
संबंधित प्रश्न
An electric fan runs from the 230 V mains. The current flowing through it is 0.4 A. At what rate is electrical energy transferred by the fan?
At a given time, a house is supplied with 100 A at 220 V. How many 75 W, 220 V light bulb could be switched on in the house at the same time (if they are all connected in parallel)?
1kWh = …….. J
Calculate the current through a 60 W lamp rated for 250 V. If the line voltage falls to 200 V, how is the power consumed by the bulb affected?
What is electric power? State and define its S.I. unit.
The electric bulbs used these days have a coil-coiled filament. State its reason.
If the rating of an electric bulb is 100W – 230V, Explain its meaning.
Unit of electric power may also be expressed as:
What is the commercial unit of electrical energy?
A family uses 8 kW of power. Direct solar energy is incident on the horizontal surface at an average rate of 200 W per square meter. If 20% of this energy can be converted to useful electrical energy, how large an area is needed to supply 8 kW?
