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
How many joules are there in one kilowatt-hour?
Write an expression for the electrical power spent in flow of current through a conductor in terms of
(a) Resistance and potential difference, (b) current and resistance.
An electric iron is rated at 750 W, 230 V. Calculate the electrical energy consumed by the iron in 16 hours .
An electric bulb marked 220 V, 100 W will get fused if it is made to consume 150 W or more. What voltage fluctuation will the bulb withstand?
The diagram 31 shows a 3 terminal plug socket.
(i) What is the purpose of the terminal E?
(ii) To which part of the appliance is the terminal E connected?
(iii) To which wire L or N, is the fuse connected and why?
What does the unit kilowatt hour measure? Define it.
Two electric lamps each rating 100 W, 110 V are connected in series to a 220 V power supply and two other electric lamps each of marking 100 W, 220 V are connected in parallel to the same power supply. Will anyone of the two combinations give more light than the other? Give a reason for your answer.
How is the amount of heat produced calculated due to the passage of current in a metallic conductor? Derive an expression for it.
How can electric energy consumed by an electric appliance be calculated in kilowatt hour (kWh)?
A student wants to use an electric heater, an electric bulb and an electric fan simultaneously.
How should these gadgets be connected with the mains? Justify your answer giving three reasons.
