All Exams Test series for 1 year @ ₹349 only
Question

What will happen to a person's weight when he is in a moving elevator?

This question was previously asked in
RRB NTPC 2015 CBT 1 Question Paper (29-Mar-2016) (Shift 1)
The correct answer is
Weight will not change

Elevator Weight Physics Explained

A person's weight is determined by the normal force ($N$) exerted by the supporting surface (the elevator floor). This apparent weight equals the true weight (gravitational force, $mg$) only when the net force is zero.

Analyzing Forces in Moving Elevator

We apply Newton's Second Law ($\Sigma F = ma$) to the person inside the elevator. The forces involved are:

  • The downward gravitational force ($mg$).
  • The upward normal force from the floor ($N$).

The net force equation is: $N - mg = ma$ where '$a$' is the acceleration of the elevator.

Scenario: Constant Velocity Motion

The question implies a scenario where the weight does not change. This occurs when the elevator moves at a constant velocity (or is at rest). In this specific case, the acceleration ($a$) is zero.

Substituting $a = 0$ into the equation:

$N - mg = m(0)$ $N - mg = 0$ $N = mg$

When $N = mg$, the apparent weight is equal to the true gravitational force. Thus, the person's weight does not change.

Conclusion: In a moving elevator at constant velocity, the apparent weight remains the same.

Was this answer helpful?

Similar Questions

  1. The rate of change of momentum of an object is proportional to the applied unbalanced force in the direction of the force. This rule is known as:
  2. What is the equation for Newton's second law of motion?
  3. What will be the resultant force if a body of mass 10 kg is moving with an acceleration of 5 m/sec2?

  4. Action and reaction forces are exerted on which bodies during an interaction?

  5. A constant force acts on an object of mass $10\text{ kg}$ for a duration of $2\text{ seconds}$. It increases the object's velocity from $5\text{ metres/second}$ to $10\text{ metres/second}$. Find the magnitude of the applied force. Now, if the force is applied for a duration of $5\text{ seconds}$, what would be the final velocity of the object?
  6. A box initially at rest is pushed with a force of 30 N to the right while friction applies a force of 30 N to the left. What happens to the motion of the box?


Important Questions from Laws of Motion

  1. Which of the following is correct?

    I. The mass of an object is a measure of its inertia

    II. In an isolated system the total momentum remains conserved

  2. A 20.0 kg block is placed on a smooth horizontal table. A horizontal force of 12.0 Newton is applied to the block. The position of the block at 5.0 sec is

  3. A subway train starts from rest at a station and accelerates at a rate of 3 ms-2 for 10s. It then runs at a constant speed for 20s and decelerates at 5 ms-2 unit it stops at the next station. The distance between the two stations is:

  4. In a desert, a beetle's motion sends fast longitudinal pulses, vL = 150 ms-1, and slower transverse pulses, vS = 50 ms-1, along the sand's surface. The sand scorpion has eight legs; spread roughly in a circle of 5 cm diameter, intercepts the faster longitudinal pulses 4.0 ms earlier than the slower transverse pulse. The pray is located at a distance of:

  5. When we jump out of a boat, the boat moves in the opposite direction. This is due to:

Need Expert Advice?
Upcoming Exams
RRB Technician
October 06, 2026
RRB JE
October 27, 2026
RRB ALP
November 03, 2026
Test Series
RRB NTPC img
Railways
RRB NTPC Under Graduate 2026 New Mock Test Series
1580 Tests 2 Tests Free
544 Attempts
4.3(498)
English, Hindi, Telugu +7 More

Start Your Preparation with Prepp Mobile App

Download the app from Google Play & App Store
Download the app from Google Play & App Store
Prepp Mobile App