Question

students are tasked with developing a model to predict how temperature fluctuations affect road longevity.
if temperatures rise, what should they expect regarding the kinetic energy of the molecules in concrete used for road construction?
a. the kinetic energy of concrete molecules decreases, resulting in greater durability in hot weather.
b. higher temperatures increase the kinetic energy but also cause the concrete to solidify, enhancing its strength.
c. the kinetic energy remains constant in concrete, regardless of temperature, a performance.
d. rising temperatures increase the kinetic energy of concrete molecules, to cracking as the material expands.

Explanation:

• Kinetic energy of molecules is directly related to temperature. As temperature rises, the kinetic energy of molecules increases.
• When the kinetic energy of concrete molecules increases (due to rising temperatures), the molecules move more vigorously. This can cause the material (concrete) to expand. If the expansion is not accommodated properly, it can lead to cracking.
• Option A is incorrect because rising temperatures increase (not decrease) kinetic energy.
• Option B is incorrect as higher temperatures do not cause concrete to solidify (concrete solidifies during the curing process, not due to a rise in temperature in the context of road longevity and temperature - related expansion).
• Option C is incorrect because kinetic energy of molecules in a material like concrete is temperature - dependent.

Answer:

D. Rising temperatures increase the kinetic energy of concrete molecules, which can lead to cracking as the material expands.