Question

You board an elevator with a large briefcase in your hand. Why does that briefcase suddenly feel particularly heavy when the elevator begins to move upward?

Answer 1

The briefcase feels heavier in an upward-accelerating elevator because the elevator must exert an additional force to overcome gravity, resulting in an increase in the apparent weight of the briefcase.

Step-by-step explanation:

When an elevator begins to move upward, we often feel as if the briefcase we're holding becomes heavier. This sensation can be attributed to the principles of physics, particularly those relating to gravitational force and acceleration. According to Einstein's observation, when an elevator accelerates upwards, the force required to overcome gravity and propel the elevator upwards is also applied to the objects inside it, including the briefcase. This additional force results in an increase in the apparent weight of the briefcase.

For example, if you are standing on a scale in an accelerating elevator, the scale would show a weight greater than your actual weight because the scale must exert an upward force greater than the gravitational force to accelerate you upward. The same applies to the briefcase; it feels heavier because it is being pushed up with more force than when the elevator is at rest or moving at a constant speed.