Question

an electric iron of resistance 25 ohm takes a current of 5 amperes calculate the amount of heat developed
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Answer 1

Correct Question:-

An electric iron of resistance 25 ohm takes a current of 5 amperes calculate the amount of heat developed in 30 s.

Given:-

• Resistance ,R = 25 Ω

• Current ,I = 5 A

• Time taken ,t = 30s

To Find:-

• Amount of heat developed ,H

Solution:-

Firstly we calculate the potential difference here

By using Ohm's law

• V = IR

Substitute the value we get

→ V = 5×25

→ V = 125 v

∴ The potential difference is 125 v.

Now , Using Joules law of heating

• H = vIt

Substitute the value we get

→ H = 125× 5 ×30

→ H = 125×150

→ H = 18750 J

→ H = 18.75 KiloJoule.

∴ The heat produce in electric iron is 18.75 Kilo joule.

Answer 2

Question

an electric iron of resistance 25 ohm takes a current of 5 ampere calculate the amount of heat developed ?

Answer

what is given here ?

• it is given that the resistance is 25 ohm
• the current is 5 A
• the time taken is 30 second

what we have to find ?

• we have to find the amount of heat developed

Solution

to find the potential difference we have to use the formula => v = IR

putting the values

=> v = 5×25

=>v=125

so the potential difference is 125v .

now

we have to use the formula H = VLT ( according to joules law of heat )

putting the values ;

H = 125×5×30

=> H = 125×150

=>H =18750 j

=> H =18•50 kg

Thus , the amount of heat developed is 18•50 kg