when 40 watts and 60 watts bulb is connected in series,
which bulb glows brightly ?

Answer Posted / wareagle

Ksb Quote "40 wattbulb has higher resistance(1440) so a
low current pass through it but 60 watt has low resistance
it glows brightly" That would be true if the bulbs are
connected in parallel but they are connected in series.
Read the question. Do you know what that means?

Ksbn That is incorrect. Lets find the answer.
Voltage = 240 volts
Watts = 40 watt and 60 watts
R60 = 240x240/60= 960 ohms
R40 = 240x240/40= 1440 ohms
Total of R60 + R40 = 960 + 1440 = 2400 ohms for series ckt
Amps = 240/2400 = 0.10 amps flowing thru both 40w and 60w
watts = amp²x R
watts for 60 watt = amp²x R = 0.10² x 960 = 0.01 x 960 =
9.6 watts
watts for 40 watt = amp²x R = 0.10² x 1440 = 14.4 watts
Therefore 40 watt is brighter.
Remember the bulbs are connected in series not parallel.

Is This Answer Correct ?    38 Yes 1 No



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