a 0.85 kg block of aluminum is heated at atmospheric pressure so that its temperature increases from 22degC to 40degC. find the work done on the aluminum? find the energy added to it by heat? find the change in its internal energy?
To find the work done on the aluminum, we can use the formula:
Work = Force x Distance x Cos(angle)
In this case, since the block is heated at atmospheric pressure, no external force is applied, and therefore no work is done on the aluminum. So the work done on the aluminum is zero.
Next, to find the energy added to the aluminum by heat, we can use the formula:
Energy added = mass x specific heat capacity x change in temperature
The specific heat capacity of aluminum is approximately 900 J/kg°C.
Energy added = 0.85 kg x 900 J/kg°C x (40°C - 22°C)
Energy added = 0.85 kg x 900 J/kg°C x 18°C
Energy added = 13770 J
Therefore, the energy added to the aluminum by heat is 13770 Joules.
Finally, to find the change in internal energy, we need to consider the total energy change, which includes both the heat added and the work done.
Change in internal energy = Energy added - Work
Change in internal energy = 13770 J - 0 J
Change in internal energy = 13770 J
Therefore, the change in internal energy of the aluminum is 13770 Joules.