Three bulbs of 40, 60 and 100 watt are connected in series with the source of 200 volt. Then which of the bulbwill be glowing the most–a)100 wattb)60 wattc)40 wattd)All are glowing equallyCorrect answer is option 'C'. Can you explain this answer?

Question

Three bulbs of 40, 60 and 100 watt are connected in series with the source of 200 volt. Then which of the bulbwill be glowing the most&#8211;a)100 wattb)60 wattc)40 wattd)All are glowing equallyCorrect answer is option 'C'. Can you explain this answer?

Answer

Resistance= (voltage)²/Power
Resistance of 40 W bulb= (200)²/40=1000 ohm
Resistance of 60 W bulb=(200)2/60=666.67 ohm
Resistance of 100 w bulb=(200)2/100=400 ohm
Total resistance= 1000+666.67+400=2066.67 ohm (addition because series circuit)
Now, we calculate current flowing in the bulbs (as we know this is series circuit so same current will flow in the circuit)
Current (I)= Voltage/total resistance=200/2066.67=0.0967 A
Now we find the power consumed by each bulb,
power consumed by 40 W bulb=I2R=(0.0967)2x1000=9.35 W
Power consumed by 60 W bulb=I2xR=(0.0967)2x666.67=6.23 W
Power consumed by 100 W bulb=I2R=(0.0967)2x400=3.74 W
From the above results, we can say that power consumed by a 40 W bulb is more as compared to other bulbs so 40 W glows brighter than other bulbs.

Answer

Resistance= (voltage)²/Power
Resistance of 40 W bulb= (200)²/40=1000 ohm
Resistance of 60 W bulb=(200)2/60=666.67 ohm
Resistance of 100 w bulb=(200)2/100=400 ohm
Total resistance= 1000+666.67+400=2066.67 ohm (addition because series circuit)
Now, we calculate current flowing in the bulbs (as we know this is series circuit so same current will flow in the circuit)
Current (I)= Voltage/total resistance=200/2066.67=0.0967 A
Now we find the power consumed by each bulb,
power consumed by 40 W bulb=I2R=(0.0967)2x1000=9.35 W
Power consumed by 60 W bulb=I2xR=(0.0967)2x666.67=6.23 W
Power consumed by 100 W bulb=I2R=(0.0967)2x400=3.74 W
From the above results, we can say that power consumed by a 40 W bulb is more as compared to other bulbs so 40 W glows brighter than other bulbs.

Answer

Explanation:

When bulbs are connected in series, the same current flows through each bulb. As the resistance of each bulb is different, the power consumed by each bulb is also different.

Formula:
Power = Voltage * Current

Let's assume the current flowing through the circuit is I.

For 40 watt bulb:
Power consumed by the 40 watt bulb is 40 W. Therefore, the current flowing through the bulb is:
40 W = 200 V * I
I = 0.2 A

For 60 watt bulb:
Power consumed by the 60 watt bulb is 60 W. Therefore, the current flowing through the bulb is:
60 W = 200 V * I
I = 0.3 A

For 100 watt bulb:
Power consumed by the 100 watt bulb is 100 W. Therefore, the current flowing through the bulb is:
100 W = 200 V * I
I = 0.5 A

As we can see, the current flowing through the 40-watt bulb is the least, and the current flowing through the 100-watt bulb is the highest.

Power consumed by each bulb:
Power consumed by 40 watt bulb = 200 V * 0.2 A = 40 W
Power consumed by 60 watt bulb = 200 V * 0.3 A = 60 W
Power consumed by 100 watt bulb = 200 V * 0.5 A = 100 W

As we can see, the 40 watt bulb consumes the least power, and the 100 watt bulb consumes the highest power.

Conclusion:

As the 40 watt bulb consumes the least power, it will glow the most. Therefore, option (c) 40 watt is the correct answer.

Answer

P=I^2.R
As all the bulbs are in series
so, same current will flow through them.
So from relation we see that,

power is directly proportional to resistance
So less is the power, lesser is the resistance & more is the glow.

Hope, it's helpful.

Answer

P=v^2/R
R=v^2/p
then resistance if 40 watt bulb is maximum
so 40watt bulb glow most

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