In a certain process 500 cal of heat is given to a system and the system does 100J of work. What will be the increase in internal energy of the system?
500 cal =2093.4 J,
ΔU = 2093.4 – 100 =1993.4 J.
To find the increase in internal energy of the system, we need to apply the first law of thermodynamics. The first law of thermodynamics states that the change in internal energy of a system is equal to the heat added to the system minus the work done by the system.
Mathematically, it can be expressed as:
ΔU = Q - W
Where:
ΔU = change in internal energy of the system
Q = heat added to the system
W = work done by the system
Given:
Q = 500 cal
W = 100 J
We need to convert the units to a common system before calculating.
1 calorie (cal) = 4.184 joules (J)
So, 500 cal = 500 * 4.184 J = 2092 J
Now, we can substitute the values into the formula:
ΔU = Q - W
ΔU = 2092 J - 100 J
ΔU = 1992 J
Therefore, the increase in internal energy of the system is 1992 Joules.