Question

At a given time, a house is supplied with 100 A at 220 V. How many 75 W, 220 V light bulbs could be switched on in the house at the same time (if they are all connected in parallel)?; A. 93; B. 193; C. 293; D. 393

Answer 1

Answer:

(C) 293

Explanation:

As per the question,

Current supplied = 100 A

Voltage = 220 V

Formula used:

Power = Voltage × Current

Power = 220 × 100

⇒ Power = 22000 Watt

Let the total number of bulbs used in the house = n

As it is given that each bulb uses 75 W power.

Therefore,

Total power used = 75 × n

And this total power used must be equal to 22000 Watt.

∴ 75 n =22000

⇒ n = 293.33

Since the number of bulbs can not be in a fraction.

Therefore, number of bulbs in the house = 293

Hence, the correct option is (C).

Answer 2

Answer:

c)293

on dividing it by total power we get 293.33 something

so approx bulb which can be switched on at the same time are 293