a 2kg steel block is originally at 10°c. if 40kj of heat energy are added to the block, what is its final temperature?
mass * specific heat * [(final temp) - 10ºC] = 40 kJ
To find the final temperature of the steel block after adding heat, we need to use the concept of specific heat capacity. The specific heat capacity is the amount of heat energy required to raise the temperature of a substance by one degree Celsius per unit mass. For steel, the specific heat capacity is typically around 0.5 J/g°C.
Here are the step-by-step calculations to find the final temperature:
1. Convert the mass of the steel block to grams: 2 kg × 1000 g/kg = 2000 g.
2. Calculate the heat energy absorbed by the steel block using the formula:
Heat energy (Q) = mass (m) × specific heat capacity (c) × change in temperature (ΔT)
Q = 40 kJ = 40,000 J (since 1 kJ = 1000 J)
m = 2000 g
c = 0.5 J/g°C
Rearranging the formula:
ΔT = Q / (m × c)
ΔT = 40,000 J / (2000 g × 0.5 J/g°C)
= 40,000 J / 1000 g°C
= 40°C
3. To find the final temperature, add the change in temperature to the initial temperature:
Final temperature = Initial temperature + ΔT
= 10°C + 40°C
= 50°C
Therefore, after adding 40 kJ of heat energy, the final temperature of the 2 kg steel block would be 50°C.