if 100W and 200W bulbs are connected in series to a supply
which bulb will glow brighter and why

Answer Posted / chaturbhuj poddar

Let us suppose that the first bulbs is marked as 100W-200V and the second bulb as 200W-200V, and both are connected in series to 200V d.c. supply to make easy calculation.
Resistance of 100W bulb R1 = V^2/P = 200*200/100 = 400 ohm,
Resistance of 200W bulb R2 = V^2/200 = 200*200/200 =200 ohm
Thus, Resistance of the combination = =600 ohm. current through each bulb = V/600= 200/600 =1/3 A
Heat produced by 100W bulb per second H1=I^2*R1=(1/9)*200J/sec
Heat produced by 200W bulb per second H2=(1/9)*400 J/s.
H2 is greater than H1. Thus, 200W bulb will glow brighter.

Is This Answer Correct ?    14 Yes 38 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

If f equals electric force, and q and q (read as: q-prime) are the charges on two particles, the expression f is proportional to q times q prime divided by distancesquared is what law?

502


What is the melting point of copper?

552


Tell me what is pascal s principle?

513


What is transverse wave motion?

537


Does gas have density?

511






What is a neutron?

542


Does water drain counterclockwise in the northern hemisphere and clockwise in the southern hemisphere?

482


Explain what is a positron?

511


This person established the one fluid theory of electricity and performed some of the first investigations into electrical grounding and insulation:

473


How does the arrangement of atoms in most solids differ from the arrangement of atoms in a liquid?

537


Explain the name for the physical constant with a value of 6.62 x 10-27 erg seconds?

493


Why does heated air expand?

540


What is the effect of using two converging lenses in one optical instrument?

483


The light in vehicle become dim when it is starting,why?

1657


Explain big bang theory?

535