Three bulbs 40W , 60W & 100W are connected to 220V
mains. Which bulb will glow brightly, if they are connected in
series?
Answers
Answer:
The 40W bulb will glow brightest.
Explanation:
Resistance of 100Wbulb=2002/100=400ohms
Resistance of 100Wbulb=2002/100=400ohmsResistance of 60Wbulb=2002/60=666.67ohms
Resistance of 100Wbulb=2002/100=400ohmsResistance of 60Wbulb=2002/60=666.67ohmsResistance of 40Wbulb=2002/40=1000ohms
Resistance of 100Wbulb=2002/100=400ohmsResistance of 60Wbulb=2002/60=666.67ohmsResistance of 40Wbulb=2002/40=1000ohmsTherefore,
Resistance of 100Wbulb=2002/100=400ohmsResistance of 60Wbulb=2002/60=666.67ohmsResistance of 40Wbulb=2002/40=1000ohmsTherefore,The 40W bulb will grow the brightest as the current is constant in all three and it has the maximum resistance. But it would consume much less than 40W as the bulbs are connected in series, and voltage would be divided across all three filaments depending upon resistances.