Question

A person normally weighing 60kg stands on a platform which oscillates up and down simple harmonically with a frequency $2Hz$ and an amplitude $5cm$.if a machine on the platform gives the person's weight,then consider the following statements :

• A. The maximum reading of machine will be $108$kg
• B. The maximum reading of machine will be $90kg$
• C. The minimum reading of machine will be $12kg$
• D. The minimum reading of the machine will be zero correct statements are:

Answer 1

Answer: (A), (C)

The correct options are
A The maximum reading of machine will be $108$kg
C The minimum reading of machine will be $12kg$

Maximum a=$w^{2}A$
$=(4\pi {)}^2\times 0.05$
$=16{\pi }^2\times 0.05$
$=8$
$mg=60\Rightarrow m=\frac{60}{10}=6$
$W_{max}=m(g+a)$
$=6\times \left(18\right)$
$=108kg$
$W_{min}=6(g-a)$=12kg