Question

A heating device is connected to 230V supply. If the current is 2A, calculate the heat produced in 5 minute

Answer 1

Answer:

138,000 joules

Explanation:

Given:

Voltage = 230 volts

Current = 2 Amperes

Time = 5 minutes

1 minute = 60 seconds

5 minutes = 5×60 = 300 seconds

To find:

Heat produced

We can say that:

heat = I²RT (or) VIT

Solving with I²RT:

$R=\frac{V}{I}$

$R=\frac{230}{2}$

$R = 115 \ ohms$

Substituting the values,

2²×115×300

= 138,000 joules

Using VIT :

=230×2×300

=138,000 Joules

The heat produced is equal to 1,38,000 joules

Answer 2

We have been given that heating device is connected to 230V supply & current is 2A in 5 minutes.

We have to find heat produced in 5 minutes.

Solution

Here, voltage = 230V

Current = 2A

Time = 5 minutes.

➲ Time = (5 × 60)s

➲ Time = 300 s

Using formula :

➺ I = V/R

➺ 2 = 230/R

➺ 2R = 230

➺ R = 230/2

➺ R = 115 ohm.

So, resistance = 115 ohm.

Using formula :

➺ Heat produced (H) = I²Rt

Putting values :

➺ Heat produced = (2)² × 115 × 300

➺ Heat produced = 4 × 115 × 300

➺ Heat produced = 138000 J

➺ Heat produced = 138 kJ

So, heat produced in 5 minutes = 138000 J or 138 kJ.