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n identical bulbs are connected in series and illuminated by a power supply . One of the bulbs gets fused. The fused bulb is removed , and the remaining bulbs are again illuminated by the same power supply. Find the fractional change in the illuminated of (a) all the bulbs and (b) one bulb.
15
Nov
n identical bulbs are connected in series and illuminated by a power supply . One of the bulbs gets fused. The fused bulb is removed , and the remaining bulbs are again illuminated by the same power supply. Find the fractional change in the illuminated of (a) all the bulbs and (b) one bulb. and [...]
Two tungsten lamps with resistances R1andR2, respectively , are connected first in parallel and then in series in a lighting circuit of negligible internal resistance. Given R1>R2. (a) Which lamp will glow more brightly when they are connected in parallel ? (b) If the lamps of resistance R1 now burns out, how will the net illumination produced change ? (c ) Which lamp will glow more brightly when they are connected in series ? (d) If the lamp of resistance R2 now burns out and lamp R1 alone is plugged in , will the net illumination increase or decrease ?
15
Nov
Two tungsten lamps with resistances R1andR2, respectively , are connected first in parallel and then in series in a lighting circuit of negligible internal resistance. Given R1>R2. (a) Which lamp will glow more brightly when they are connected in parallel ? (b) If the lamps of resistance R1 now burns out, how will the net [...]
A fuse with a circular cross sectional radius of 0.15 mm blows at 15 A . what should be the radius of the cross section of a fuse made of the same material that blows at 30 A?
15
Nov
A fuse with a circular cross sectional radius of 0.15 mm blows at 15 A . what should be the radius of the cross section of a fuse made of the same material that blows at 30 A? A fuse with a circular cross sectional radius of 0.15 mm blows at 15 A . what [...]
An electric motor operating on a 50 V dc supply draws a current of 12 A. If the effenciency of the motor is 30 % estimate the resistance of the windings of the motor .
15
Nov
An electric motor operating on a 50 V dc supply draws a current of 12 A. If the effenciency of the motor is 30 % estimate the resistance of the windings of the motor . An electric motor operating on a 50 V dc supply draws a current of 12 A. If the effenciency of [...]
A house is fitted with seven tubelights of rating 220V,40W each , two bulbs of rating 220V,60Weach, five fans each drawing a current of 0.4at220V, and a heater of resistance 48.4Ω. The main line power supplied to the house is at 220V. Calculate the bill for the month of january if tubelights and bulbs are used for 6h daily, fans for 1h daily , and heater for 10h daily. The electricity is to cost Rs.2per unit.
15
Nov
A house is fitted with seven tubelights of rating 220V,40W each , two bulbs of rating 220V,60Weach, five fans each drawing a current of 0.4at220V, and a heater of resistance 48.4Ω. The main line power supplied to the house is at 220V. Calculate the bill for the month of january if tubelights and bulbs are [...]
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40W each ,
60Weach ,
A house is fitted with seven tubelights of rating 220V ,
and a heater of resistance 48.4Ω. The main line power supplied to the house is at 220V. Calculate the bill for the month of january if tubelights and bulbs are used for 6h daily ,
and heater for 10h daily. The electricity is to cost Rs.2per unit. ,
fans for 1h daily ,
five fans each drawing a current of 0.4at220V ,
two bulbs of rating 220V ,
Two wires of the same material and having the same uniform area of cross section are connected in an electric circuit. The masses of the wires are mand2m, respectively. When a current I flows through both of them connected in series, then find the ratio of heat produced in them in a given time .
15
Nov
Two wires of the same material and having the same uniform area of cross section are connected in an electric circuit. The masses of the wires are mand2m, respectively. When a current I flows through both of them connected in series, then find the ratio of heat produced in them in a given time . [...]
Tags:
respectively. When a current I flows through both of them connected in series ,
then find the ratio of heat produced in them in a given time . ,
Two wires of the same material and having the same uniform area of cross section are connected in an electric circuit. The masses of the wires are mand2m ,
We have a 30 W , 6 V bulb , which we want to glow by a supply of 120 V . what can be done for this ?
15
Nov
We have a 30 W , 6 V bulb , which we want to glow by a supply of 120 V . what can be done for this ? 6 V bulb We have a 30 W which we want to glow by a supply of 120 V . what can be done for this [...]
Water boils in an electric kettle in 15 min after being switched on. Using the same main supply , should the length of the heating element be increased or decreased if th ewater is to be boiled in 10 min? why ?
15
Nov
Water boils in an electric kettle in 15 min after being switched on. Using the same main supply , should the length of the heating element be increased or decreased if th ewater is to be boiled in 10 min? why ? should the length of the heating element be increased or decreased if th [...]
A house is fitted with certain numbers of 100 W, 230 V incandescent lamps. The power to the house is fed by a generator producing the power at 240V. The resistance of the wires from the generator to the house is 2Ω. Find the maximum number of lamps that can be illuminated so that the voltage across none of the lamps drops below 230 V.
15
Nov
A house is fitted with certain numbers of 100 W, 230 V incandescent lamps. The power to the house is fed by a generator producing the power at 240V. The resistance of the wires from the generator to the house is 2Ω. Find the maximum number of lamps that can be illuminated so that the [...]
Each of the three resistors in figure has a resistance of 2 ohm and can dissipate a maximum of 18 W without becoming excessively heated. Find the maximum power the circuit can dissipate .
15
Nov
Each of the three resistors in figure has a resistance of 2 ohm and can dissipate a maximum of 18 W without becoming excessively heated. Find the maximum power the circuit can dissipate . Each of the three resistors in figure has a resistance of 2 ohm and can dissipate a maximum of 18 W [...]