Question

A bulb is rated 5V; 500mA. Calculate the rated power and resistance of the bulb when it glows

Answer 1

10ohm it will be I = 0.5A , V = 5V V = IR

V= 5V
I= 500mA = 500/1000= 0.5A
V= IR
5 = O.5 * R
5/0.5 = R
50/5 = R
10 ohm = R
hope it is correct. it is correct

Answer 2

Answer:

100 ohm

Explanation:

Given,

Potential difference, V=5V

current,I= 500 mA = 500×10‐³ = 500/1000=0.5A

We know, By Ohm's law,

V=IR

R=V/I

=5/0.5

=5/(5/10)

=(5×10)/5

=10ohm------(1)

Now when the bulb glows,

P=VI

=5×0.5

=5×(5/10)

=2.5 Watt

Now, (1) × 10 Watt,

=10 ×10

=100 ohm