Question

A group of students performed an experiment to prove the law of conservation of energy. In the experiment, a flask containing water at room temperature was shaken vigorously for a few minutes. The table shows a partial record of the temperature of the water before and after shaking.

Experimental Record
Temperature
Before Shaking 20 °C
After Shaking Unknown
What best predicts the unknown temperature? (3 points)

a. Less than 20 °C because the total energy of the system after shaking is lower

b. Greater than 20 °C because the total energy of the system after shaking is higher

c. Less than 20 °C, because the mechanical energy from shaking transforms to thermal energy

d. Greater than 20 °C, because the mechanical energy from shaking transforms to thermal energy

Answer 1

The answer is B hope this helps

Answer 2

Less than 20 °C

Step-by-step explanation:

Based on the experimental record, the best prediction for the unknown temperature after shaking the flask containing water is:

c. Less than 20 °C, because the mechanical energy from shaking transforms to thermal energy.

When the students shook the flask vigorously, they applied mechanical energy to the system. This mechanical energy was then transformed into thermal energy due to the friction between the water molecules.

Since energy is conserved according to the law of conservation of energy, the total energy of the system after shaking will be the same as before shaking. However, some of the mechanical energy has been converted into thermal energy, which causes an increase in the temperature of the water.

Therefore, the unknown temperature after shaking is expected to be less than 20 °C. This is because the mechanical energy from shaking has been converted into thermal energy, causing an increase in the water's temperature.