Question

Which best describes what happens to metal railroad tracks on a hot, summer day?

Answer 1

On a hot summer day, metal railroad tracks expand due to the increase in temperature. As the metal heats up, its molecules move more vigorously, causing the tracks to lengthen. This phenomenon is known as thermal expansion. If the tracks cannot expand freely due to constraints (like being anchored too tightly), it can lead to buckling or warping, creating potential hazards for trains. Therefore, railways must be carefully engineered to accommodate this expansion and prevent track distortion.