A helicopter of mass 2000 kg rises with a vertical acceleration of `15m s^(-2)`. The total mass of the crew and passengers is 500 kg. Choose the correct statements from the following. `("Take g"= 10ms^(-2))`
(i) The force on the floor of the helicopter by the crew and passengers is `1.25 xx 10^(4)N` vertically downwards.
(ii)The action of the rotar of the helicopter on the surrounding air is `6.25xx10^(4)` vertically downwards.
(iii) The force on the helicopter on the surrounding air is `6.25xx10^(4)N` vertically upwards.

Explanation

Given, mass of helicopter `(m_(1))=2000 kg`
mass of the crew and passengers `m_(2)=500 kg`
Acceleration in vertical direction `a=15 m//s^(2) (uarr)` and `g=1-0 m//s^(2)darr`
(a) Force on the floore of the helicopter by the crew and passengers
`m_(2)(g+a)=500(10+15)N`
`500 xx25 M=12500 N`
(b) Action of the rotore of the helicopter on the surrounding air `=(m_(1)+m_(2))(g+a)`
`200+500)xx(10+15)=2500xx25`
`=62500 N` (downwards)
(c) force on teh helicopter due to the surrounding air
reaction of force applied by helicopter.
`62500 N` (Upwards)