A person weighs $60 k g$ . He stands on a weighing machine in a lift which is moving.
(i) upward with uniform speed $5 m / s$ .
(ii) downward with a uniform acceleration $4 m / s^{2}$ .
(iii) upward with a uniform acceleration $4 m / s^{2}$ .
What would be the reading on the scale in each case?
(Take $g = 10 m / s^{2}$ )

Open in App

Solution

(i) $↑ v = 5$
$g^{1} = g$
$m g \Rightarrow 60 \times 10 = 600 N$

(ii) $↓ a = 4$
$g^{1} = (g - a)$
$\Rightarrow 6$
$m g \Rightarrow 60 \times 6 = 360$

(iii) $↑ a = 4$
$g^{1} = (g + a)$
$\Rightarrow 14$
$m g \Rightarrow 60 \times 14$
$\Rightarrow 840 N$

Suggest Corrections

Similar questions

Q. A man weighs

80 k g

. He stands on a weighing scale in a lift which is moving upwards with a uniform acceleration of

5 m / s^{2}

. What would be the reading on the scale? (

g = 10 m / s^{2}

)

Q. A man weighs 80 kg He stands on a weighing scale in a lift which is moving upwards with a uniform acceleration of

5 m / s^{2} .

What would be the reading on the scale ?

(g = 10 m / s^{2})

A $70$ kg man standing on a weighing scale in a lift which is moving a) upward with a uniform speed of $10 m / s$ , b) downward with a uniform acceleration of $5 m / s^{2}$ , c) upward with a uniform acceleration of $5 m / s^{2}$ . The reading of the scale in each case?