Question

Experienced hikers prefer to step over a fallen log in their path rather than stepping on top and stepping down on the other side. Explain.

Short answer

Hikers do this to conserve energy.

Step-by-step solution

Understanding the goal of hikers

Hikers try to conserve energy, as they need to walk for long hours.

Comparing both the situations

When hiker steps on the log, he or she has to do some work against the ground to rise body at some height above the ground, and as hikers try to conserve energy, they choose to step over a fallen log. (No work needs to be done against gravitational pull in this case.)