Question

In above figure which bulb will get fuse ??

State the reason for your answer .

⭐A perfect answer required ! Thanks!

Be Brainly !!

Answer 1

Hey mate,

We can observe that the voltage remains constant in both the cases = 220V,

Bulb with lower power will have high resistance.

We will use formula R = V^2/P

When both bulbs are connected in series, the resistance will add up.

In series combination the bulb with higher resistance will handle more voltage,
So, 50 W will fuse first,

Calculations :-

R(50) = 220^2/50

= 968 ohms

R(100) = 220^2/100

= 484 ohms

Total R = 1452

We know,

V = I*R

So,

I = 440/1452

= 0.30 amp

Now V across 50W,

0.30*968 = 290.4 V

V across 100W,

0.30*484 = 145.2 V

You can see here that 50W will fuse due to high voltage.

But 100 W will glow with low intensity.

Hope this helps you out!