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## Homework Statement

A Heating Element rated 1400Watt Supply 220V

Current : 6.36 Amperes

Resistance = 34.57 Ohms

Area to be heated L X B X H = 4inches X 4inches X 9inches

From Temperature 35 Deg.C to 1000 Deg.C

All under standard/normal pressure

**2. Relevant Question**

How long would it take to heat from 35 Deg.C to 1000 Deg.C

## The Attempt at a Solution

**Joules = Mass(Kg) X Heat Capacity on kJ/Kg.DegC X Delta T**

Inch(s) -> to Meter(s)

4 -> 0.1016

4 -> 0.1016

9 -> 0.2286

Therefore Volume of Air = 0.00235974 Mt^3

Density of Air @ 35. Deg C = 1.1455 Kg/Mt^3

Amount of Air @ 35. Deg C = 0.00235974 X 1.1455 = 0.0027031 Kg

Heat Capacity of Air = 1.06 kJ/kg Deg.C

Delta T = 1000 - 35 = 965 Deg.C

Joules to be consumed = 0.0027031 x 1.06 X 965 = 2.76499 kJ = 2764.99 Joules

**Joules = Current^2 X resistance X time(Seconds)**

Then 27466.99 = (6.36)^2 X 34.57 X T(Seconds)

**or, T = 1.97 Seconds (Something is wrong)**

**Time=? (to raise the temperature from 35 Deg.C to 1000 Deg.C)**

## The Attempt at a Solution

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