Determine the mass of a steel hammer if, when it is heated from 52 degrees to 20 degrees, 300 kJ

Determine the mass of a steel hammer if, when it is heated from 52 degrees to 20 degrees, 300 kJ of heat is released. (specific heat of steel 500 J / kg degrees)

We start the solution with a short note given:

Q = 300 kJ = 300,000 J;

t1 = 52 ° C;

t2 = 20 ° C;

c = 500 J / kg * ° С.

Find m -?

Decision:

Let’s apply the formula to calculate the mass

Q = cm (t1 – t2) is a formula for calculating the amount of heat released when the body temperature changes from t1 to t2.

Where C is the specific heat of a body (can be found from the table of specific heats), and m is the mass of the body.

We express the mass from the formula:

m = Q / c (t1 – t2).

Substitute values and perform calculations:

m = 300,000 J / 500 J / kg * ° C * (52 ° C – 20 ° C);

m = 18.75 kg.