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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?
A bulb of 40 W is used for 12.5 h each day for 30 days. Calculate the electrical energy consumed.
The coil of an electric bulb takes 40 watts to start glowing. If more than 40 W are supplied, 60% of the extra power is converted into light and the remaining into heat. The bulb consumes 100 W at 220 V. Find the percentage drop in the light intensity at a point if the supply voltage changes from 220 V to 200 V.
The diagram below shows a magnetic kept just below the conductor AB which is kept in North South direction.
(i) In which direction will the needle deflect when the key is closed ?
(ii) Why is the deflection produced ?
(iii) What will be the change in the deflection if the magnetic needle is taken just above the conductor AB ?
(iv) Name one device which works on this principle.
Name the physical quantity which is measured in kW.
Mention three uses of the carbon arc.
Name a metal that is used as an electron emitter. Give one reason for using this metal.
An electric bulb is rated as 100W – 250V. What information does it convey? Calculate the current through the filament of the bulb.
An Electric bulb is marked 100 W, 230 V. What how long would this lamp take to consume one unit of electricity?
Using a long extension cord in which each conductor has a resistance of 8Ω, a bulb marked as '100 W, 200 V' is connected to a 220 V dc supply of negligible internal resistance as shown in the figure. The power delivered to the bulb is ______ W.
