Question
Question: A sample of liquid in a thermally insulated container (a calorimeter) is stirred for 2 hr. by a mech...
A sample of liquid in a thermally insulated container (a calorimeter) is stirred for 2 hr. by a mechanical linkage to a motor in the surrounding, for this process :
A
w< 0; q = 0; DU = 0
B
w > 0; q > 0; DU > 0
C
w< 0; q > 0; DU = 0
D
w > 0; q = 0; DU > 0
Answer
w > 0; q = 0; DU > 0
Explanation
Solution
Mechanical work is done on the system and internal energy increases.