 # A helicopter of mass 2000 kg rises with a vertical `
Question:

A helicopter of mass 2000 kg rises with a vertical acceleration of 15 m/s2. The total mass of the crew and passengers is 500 kg. Give the magnitude and direction of the

(a) force on the floor of the helicopter by the crew and passengers

(b) action of the rotor of the helicopter on the surrounding air

(c) force on the helicopter due to the surrounding air

Solution:

Given,

Mass of helicopter, M = 2000 kg

Mass of the crew and passenger, m = 500 kg

Acceleration of helicopter with crew and passengers = 15 m/s2

a) Force on the floor of the helicopter by the crew and passenger = m(g + a) = 500(10 + 15)

F1 = (500)(25) = 12500 N

b) Action of the rotor of the helicopter on the surrounding air is force F2.

The acceleration due to Newton’s third law is when acceleration is 15 m/s = (M + m)(g + a)

= (2000 + 500) (g + a)

= 2500(10 + 15)

= 62500 N

c) Force on the helicopter due to the surrounding air is F3.

F3 = Action force = – 62500 N or + 62500 N