In an elevator moving vertically up with an acceleration g, the force exerted on the floor by a passenger of mass M is:
A
Mg
B
21Mg
C
Zero
D
2Mg
Step-by-Step Solution
Identify Forces: The passenger in the elevator experiences two forces:
Gravitational force (Weight) acting downwards: W=Mg.
Normal reaction force exerted by the floor acting upwards: N.
Apply Newton's Second Law: For a body accelerating upwards with acceleration a, the net force is upwards.
Fnet=N−Mg=Ma
Solve for Normal Force (Apparent Weight):N=M(g+a)
Substitute Given Acceleration: The problem states the upward acceleration is equal to the acceleration due to gravity (a=g).
N=M(g+g)=M(2g)=2Mg
Conclusion: According to Newton's Third Law, the force exerted by the passenger on the floor is equal in magnitude to the normal reaction N. Thus, the force is 2Mg.
(Reference: NCERT Class 11, Physics Part I, Chapter 5: Laws of Motion, dealing with apparent weight in accelerated frames).
Practice Mode Available
Master this Topic on Sushrut
Join thousands of students and practice with AI-generated mock tests.