Question

Calculate the energy transferred when 2a current flows through a 10 ohm resistor for 30 minutes

Answer 1

when 2 Amps of current flows through a 10 ohm resistance, the total power dissipated in the circuit will be,
P = V*I watts

Now by ohms law we know that ,
V = I*R

therefore,

P = (I*R)*I

given I= 2A R= 10 ohm

P = (2*10)*2 = 40 watts

Power is defined as work done per unit time.

therefore P = W/t
W = P*t
W = 40*30*60*60 (converting minutes to seconds)
W = 4320000 Joules or 4320 Kilo Joules

Answer 2

As we know

$\boxed{POWER = POTENIAL DIFFERENCE*CURRENT}$

But here the values given are

Current = 2A

Resistance = 10Ω

So the fomula

P = I²R is used

Substituting the values, we get

P = (2)²(10)

= 40W

As we know

power = work done / time taken

40 = work /1800    ( 30*60 = 1800s)

work = 72000J or 72 KJ