Question

18. A torch bulb is rated 5V and 500mA. Calculate the
a. Power
b. Resistance
c. Energy consumed when it is lighted for 4 hours​

Answer 1

Answer:

Explanation:

Hope this helps you,take care of conversions and rest is basic concept

Answer 2

V = 5Volts

I = 500 mA

That is :-

$= 500 \times {10}^{( - 3)} \\ \\ = 0.5 \: ampere$

Hence,

We know :-

P= VI

So,

Power = 5*0. 5 = 2.5 Watt

Resistance will be :-

V = IR

R = V/I

R= 5/0.5 = 10 ohms

Energy will be :-

Energy = Power * Time

Energy = 2.5 * 60*4*60 watt sec

Energy = 36000 Joules

Energy = 36 kilo Joules

To find the energy we can also apply the Joule's law of heating effect.

We can also use the formula :-

H=I²RT

To find the energy or heat released as we have all the variables.

Answer!