Çözüldü Dynamics

If the weight of an object is measured by a scale on the bottom of a moving elevator and it is observed that the scale’s indication is more than the weight of the object when the elevator is at rest, then which of the following judgments is correct about the object’s movement?

A) Upward at constant speed
B) Stops by decelerating while moving upward
C) Upward by accelerating
D) Downward by accelerating
E) Downward at constant speed

The correct judgment is C) Upward by accelerating, because the scale shows a greater apparent weight (normal force) when the elevator accelerates upward, making the object heavier than at rest and the apparent weight (N) equal to m·(g + a) where (g) is gravity.

Notes:
Apparent Weight (N): The force exerted by the scale on the object.
At Rest or Constant Speed: (N = m·g) (weight is normal).
Upward Acceleration (a is upward): N - m·g = m·a ⇒ N = m·(g + a) (weight is greater).
Downward Acceleration (a is downward): N + m·a = m·g ⇒ N = m·(g - a) (weight is less).