Question

An electric heater of resistance 500 ohms is connected to a main supply for 30 minutes. if
5A current flows through the filament of heater, then calculate the heat energy produced in the heater

Answer 1

We have to calculate the heat energy produced in the heater when the electric heater is of resistance 500 ohms.

And the time of main supply is 30 minutes.

The given Current = I = 5A

Time = 30 minutes.

Converting this time into seconds = 30 × 60 = 1800 seconds.

We know the formula to find heat energy, that is :

H = I²Rt

So ,

H = (5)²×500×1800

= 22500000 J = 2.25 × 10^7

The required heat energy produced in the heater is 2.25 × 10^7 J

Answer 2

Answer:- 5.3 × 10³ Kcal.

Step by Step Solution:-

Given that,

Resistance(R) = 500 Ω

Time(t) = 30 minutes = 30×60 = 1800 seconds

Current(i) = 5 A

We know  that,

Energy Generated by  heater,

H = i² × R × T

H = 5 × 5 × 500 × 1800

H = 2250 × 10⁴ J

H = 2.25 × 10⁷ J

H = 2.25/4.18 × 10⁷ cal.

H = 0.53 × 10⁷ cal.

H = 0.53 × 10⁴ Kcal.

H = 5.3 × 10³ Kcal.