Question

Suppose there are a number of bulbs rated at 220V – 100W each.
How many bulbs can be connected in parallel across a 220V supply
line, if the maximum permissible current is 5A only?
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Answer 1

Answer:

if we are supposing everything then why don't you imagine the answer

please don't report the answer I was joking I am solving will edit my answer

Answer 2

Solution:

As per the given data ,

• Power( P)  = 100 W
• Voltage (V) = 220 V

First let us find the resistance of each bulb.

We know that ,

⇒ P = V ² / R

On rearranging ,

⇒ R = V ² / P

⇒ R = 220 x 220 / 100

⇒ R = 22 x 22

⇒ R = 484 Ω

Equivalent resistances for n no of resistances connected in parallel is given by the formula ,

⇒ 1 / Rp = 1 / R 1 + 1 / R 2 + 1 / R 3 .... + 1 / Rn  

Consider ,n number of resistors of the same resistance are connected in parallel to each other .

Hence ,

⇒ 1 / Rp = n / R

⇒ Rp = R / n

⇒ Rp = 484 / n

By applying ohm's law ,

⇒ V = I Rp

⇒ Rp =  V / I

⇒ Rp = 220 / 5

⇒ 484 / n  = 44

⇒ n = 484 / 44

⇒ n = 11

Total number of bulbs connected in parallel is 11  .