What is the minimum amount of water needed to quench a hot steel knife blade?

Calculation of Minimum Amount of Water Needed

When quenching a hot steel knife blade in water, we need to ensure that the water temperature does not rise above the boiling point. To calculate the minimum amount of water required for this process, we can use the principle of heat exchange between the steel blade and the water.

Given that the specific heat of the steel blade is 0.11 cal/g-C and its mass is 80g, and the maximum temperature reached by the blade is 400C, we can determine the minimum amount of water needed.

Since the final thermal equilibrium temperature for both the steel blade and water is 100C, the maximum allowable change in temperature will be 300C for the blade and 80C for the water.

Using the equation for heat exchange through conduction, we can set up the following equation:

cs*mk*Δtk = cw*mw*Δtw

Where:
cs = specific heat of steel blade
mk = mass of steel blade
Δtk = change in temperature of steel blade
cw = specific heat of water
mw = mass of water
Δtw = change in temperature of water

By substituting the given values into the equation and solving for mw, we can determine the minimum amount of water needed to quench the steel blade without exceeding the boiling point temperature.