Question

a swimming pool is an example of an open system. according to the law of conservation of energy, if swimmers add 1,500 j of thermal energy to the pool and the surrounding air adds 2,500 j of thermal energy, what is the total change in energy?
a. an increase of 2,500 j
b. an increase of 1,500 j
c. an increase of 1,000 j
d. an increase of 4,000 j

Explanation:

Step1: Identify energy contributions

The swimmers add 1500 J and air adds 2500 J.

Step2: Calculate total energy change

The total change in energy is the sum of the two contributions, so $1500 + 2500$.
$1500+2500 = 4000$ J. Since energy is added, it's an increase.

Answer:

D. An increase of 4,000 J