Elevator Physics: How Your Apparent Weight Changes When the Car Stops

Stand on a scale in an elevator—your reading (apparent weight) changes as the car accelerates, decelerates, or moves at constant velocity.

Scenario: Elevator Slowing to Stop at a Floor (Moving Upward)

1. Deceleration phase: The car accelerates downward (negative acceleration) to reduce upward speed.
   • Net force on you: N – mg = –ma → N = m(g – a)
   • Apparent weight < actual weight. You feel lighter.
2. Momentary stop: Acceleration = 0 → N = mg. Scale reads true weight.
3. Starting upward again: Acceleration upward (+a).
   • N – mg = +ma → N = m(g + a)
   • Apparent weight > actual weight. You feel heavier.

Magnitude of Change

Typical elevator acceleration: 1–2 m/s² (0.1–0.2 g).

• At 2 m/s² deceleration: apparent weight = 80% of actual.
• At 2 m/s² acceleration: apparent weight = 120% of actual.

Key Insight

Apparent weight changes only during acceleration. Constant velocity (up, down, or stopped) feels exactly like standing on solid ground. The direction of acceleration, not velocity, determines whether you feel heavier or lighter.