Question

An electric lift is moving downward with an acceleration of $g/3$ . the vertical force between a passenger in the lift and its floor is equal to

• A. 3/4 of the passenger's weight
• B. 2/3 of the passenger's weight
• C. passenger's weight
• D. 4/3 of the passenger's weight

Answer 1

The correct option is B 2/3 of the passenger's weight

$\frac{w}{g}a=w-R$

$\therefore R=w-\frac{w}{g}a$

$a=\frac{g}{3}$

$\therefore \frac{a}{g}=\frac{1}{3}$

$=w[1-\frac{a}{g}]$

$=w[1-\frac{1}{3}]=w\left[\frac{2}{3}\right]$

$R=\frac{2}{3}w$