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A person of mass m is on the floor of a ...

A person of mass m is on the floor of a lift. The lift is moving down with an acceleration 'a'. Then :
a) the net force is acting in downward direction and is equal to mg
b) the force mg must be greater than reaction force
c) the man appears to be lighter than his true weight by a factor (a/g)

A

a, b, c are correct

B

b and c are correct

C

a and c are correct

D

only b is correct

Text Solution

Verified by Experts

The correct Answer is:
B
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AAKASH SERIES-LAWS OF MOTION-EXERCISE - I
  1. A man of mass m is on the floor of a lift. The lift moving up with acc...

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  2. A man of mass m is on the floor of a lift. The lift moving up with acc...

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  3. A person of mass m is on the floor of a lift. The lift is moving down ...

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  4. Statement A : If the lift is falling freely then the man on its floor ...

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  5. Statement A : If the force varies with time in a complicated way then ...

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  6. Statement A : Shock absorbers reduce the magnitude of change in moment...

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  7. Two blocks A and B of the same mass and surface finish are sliding on ...

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  8. A good lubricant should be highly

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  9. Theoretically which of the following are best lubricants

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  10. A block of mass'm' is resting on the floor of a lift. The coefficient ...

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  11. When a moving body is suddenly stopped a long time after coming to res...

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  12. A block 'B' rests on 'A'. A rests on a horizontal surface 'C which is ...

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  13. Sand is dusted on the railway tracks during rainy season to

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  14. Which of the following are correct for rolling friction

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  15. If an external force and the frictional force acting on a body cancel ...

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  16. Which of the following statements is not true ?

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  17. When normal reaction is halved the coefficient of friction is

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  18. Match the items mentioned in the lists I and II below LIST -1 a) S...

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  19. With increase of temperature, the frictional force acting between two ...

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  20. If we imagine two ideally smooth surfaces & if they are kept in contac...

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