A 2.50*10^2-kg cast-iron car engine contains water as a coolant. Suppose that the engine's temperature is 35.0º Celsius when it is shut off, and the air temperature is 10.0º Celsius. The heat given off by the engine and water in it as they cool to air temperature is 4.40*10^6 Joules. What mass of water is used to cool the engine?
Please help me with this problem.
I'm having trouble understanding this.
2007-02-03 12:51:23 · 1 answers · asked by swimmertommy 1 in Science & Mathematics ➔ Physics
You need to use the equation Q = m c ΔT
Q is the quantity of energy absorbed or given off
m is the mass of the object
c is the specific heat
ΔT is the change in temperature
Since you have two objects giving off the heat, you will need an mcΔT for both of them. So:
Q = (mcΔT)for iron + (mcΔT)for water
You will need the specific heat of iron and of water. When you substitute into the above equation everything that you know, you will find that you have one unknown, namely the mass of water. Rearrange and solve.
2007-02-03 13:17:35 · answer #1 · answered by Ben C 2 · 1⤊ 0⤋