Question

Two electric bulbs marked 25W – 220V and 100W – 220V are connected in series to a 440Vsupply. Which of the bulbs will fuse?
A) 25 W
B) Both
C) 100 W
D) Neither

Answer 1

Hey there! ☺☻☺

Let R₁ and R₂ be the resistance of both the bulbs.
Rating of First bulb = 25 W  - 220 V = R₁
Rating of Second bulb = 100 W - 220 V = R₂

We know,
P = V²/R
∴ R = V²/P

Now,
R₁ = (220)² / 25
     = 48400/25
     = 1936 ohm
R₂ = (220)₂ / 100
     = 48400/100
     = 484 ohm

Hence, R₁ > R₂.
And, V $\propto$ R
So, voltage will be more in R₁. 

Hence, 25 W bulb will fuse.

Hope It Helps You! ☺☻☺

Answer 2

Thus so

LET THE TWO RESISTANCE OF THE BULBS BE R1 AND R2

RATING 1 - 25W - 220 V

RATING 2 - 100 W - 220 V

THUS
WE KNOW
➡ P = VI
➡ P = V² / R
➡ R = V² / P

SO
↪ R1 = 220 ² / 25
. = 48400 / 25
. = 1936 OHM

↪ R2 = 220 ² / 100
. = 48400 / 100
. = 484 OHM

➡ AS
. R1 > R2
. ALSO ( V ) IS DIRECTLY PROPORTIONAL TO ( R )

THUS
➡ VOLTAGE IS MORE IN R1

➡ THUS 25 W BULB WILL FUSE

HENCE A . 25 W

Hope it helps

. @g always there . . On brainly .