Apparent weight in free fall When a body falls freely under the action of gravity (e.g., in an ideal freely falling elevator), what happens to its apparent weight?

Introduction / Context:
Apparent weight is the normal reaction measured by a scale. In free fall, many systems experience weightlessness, a key idea in astronautics and drop-tower experiments. Distinguishing true gravitational weight from the apparent weight is essential.

Given Data / Assumptions:

• Body is in ideal free fall under gravity alone (acceleration g downward).
• No air resistance; we evaluate the scale reading or normal reaction.
• “Weight” in this context refers to apparent weight (scale reading).

Concept / Approach:

A scale measures the normal reaction R. For a body of mass m on a scale in an elevator with acceleration a downward, R = m(g − a). In free fall, a = g, hence R = 0. The gravitational force mg still acts, but the apparent weight (what the scale reads) is zero, producing weightlessness.

Step-by-Step Solution:

Verification / Alternative check:

Free-body diagram shows only gravity acting, with the supporting contact lost; without a normal force, scales read zero. Astronaut training aircraft simulate brief weightlessness during parabolic flight for the same reason (effective acceleration equals g downward).

Why Other Options Are Wrong:

(a) and (b) imply extremes of apparent weight but not zero. (d) claims no change, which contradicts the zero-reaction result. (e) is physically meaningless for weight in this scenario.

Common Pitfalls:

Confusing true weight mg (unchanged) with apparent weight (scale reading); thinking zero gravity is required for weightlessness—it is sufficient that support force is zero.

Final Answer:

no weight