MCQ
Given below are two statements:

Statement$-I :$ An elevator can go up or down with uniform speed when its weight is balanced with the tension of its cable.

Statement$-II :$ Force exerted by the floor of an elevator on the foot of a person standing on it is more than his/her weight when the elevator goes down with increasing speed.

In the light of the above statements, choose the correct answer from the options given below :

  • A
    Both statement $I$ and statement $II$ are false
  • Statement $I$ is true but Statement $II$ is false
  • C
    Both Statement $I$ and Statement $II$ are true
  • D
    Statement $I$ is false but Statement $II$ is true

Answer

Correct option: B.
Statement $I$ is true but Statement $II$ is false
b
When elevator is moving with uniform speed $T = F _{ g }$

Statement$-2$

When elevator is going down with increasing speed, its acceleration is downward.

Hence 

$W - N =\frac{ W }{ g } \times a$

$N = W \left(1-\frac{ a }{ g }\right) \text { i.e. less than weight. }$

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