Question

A 5.0-kg wood block starts with an initial speed of 8.0 m/s and slides across the floor until friction stops it. Estimate the resulting change in entropy of the universe. Assume that everything stays at a room temperature of 20°C.

a) 0 J/K

b) Positive value

c) Negative value

d) Cannot be determined

Answer 1

The resulting change in entropy of the universe is Negative value

Therefore, correct answer is c) Negative value

Step-by-step explanation:

The change in entropy of the universe is linked to the concept of irreversibility in processes. In the case of the wood block sliding across the floor and coming to a stop due to friction, this process is inherently irreversible. The initial kinetic energy of the block is converted into thermal energy due to friction, leading to an increase in the entropy of the system. According to the second law of thermodynamics, entropy tends to increase in natural processes, and as the block loses its ordered motion, the entropy of the universe increases. Therefore, the resulting change in entropy is a negative value.

The second law of thermodynamics and how it governs the direction of natural processes, emphasizing the concept of entropy as a measure of system disorder and irreversibility.

Therefore, correct answer is c) Negative value