Question

if a 100 W light bulb and a 75 W light bulb operate from 220 V the _____ bulb has a greater current in it

1).75 W
2). 100 W

Answer 1

Higher wattage means that the bulb will draw more current to it.

100W is more than 75W, so the answer is 2) 100W.

Answer 2

Answer: The correct answer is 100 W.

Explanation:

The expression for the power in terms of voltage and the current is as follows;

P=VI                                                                    .......... (1)

Here, P is the power, V is the voltage and I is the current.

It is given in the problem that a 100 W light bulb and a 75 W light bulb operate from 220 V .

Calculate the current for light bulb, 100 W by rearranging the above expression.

Put P= 100 W and V= 220 V.

$I=\frac{100}{220}$

I= 0.45 A

Calculate the current for light bulb, 75 W by expression (1).

Put P= 75 W and V= 220 V.

$I=\frac{75}{220}$

I= 0.34 A

Therefore, 100 W light bulb has a greater current in it