Question

⚡⚡⚡A house has main fuse of 5 ampere rating of 60 watt and 2 tube lights each of 40 watt are used simultaneously.

I) how much current is drawn from the mains of 220 volt?

ii) how many more bunch of hundred word can also be lighted on a festival day?

Answer 1

ANSWERS :-


(I) Total power of appliances used simultaneously

p = (5 * 60) + (2 * 40 )

= 300 + 80

= 380 W

voltage of mains V = 220 volts

current drawn from the mains

I = p/ v

= 380 / 220

= 1.73 Ampere

ii) excess current available which can be safely used = 5 A - 1.73 A
= 3.27 A

current drawn by each 100 W bulb at 220 v ,

I = p/ v

= 100/ 220

= 0.45 A

so,

number of 100 W bulbs which can be lighted on a festival day

n = 3.27 / 0.45

= 7.3

so,

seven more bulbs can be lighted.

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❤BE BRAINLY ❤
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