A helicopter of mass 1000 kg rises with a vertical acceleration of 15 ms -2 . The crew and the passengers weigh 300 kg. The magnitude of the action of the rotor of the helicopter on the surrounding air is

Question

A helicopter of mass 1000 kg rises with a vertical acceleration of 15 ms -2 . The crew and the passengers weigh 300 kg. The magnitude of the action of the rotor of the helicopter on the surrounding air is (A) 2 × 103 N (B) 3.25 × 104 N (C) 3.5 × 104 N (D) 7.5 × 103 N

Tardigrade Admin · Accepted Answer

The required action is equal and opposite to the force on the helicopter due to the surrounding air. F-m g=m a F=m(g+a) =(1000 ] kg +300 kg )(10 ms -2+15 ms -2) =(1300)(25) N =3.25 × 104 N

Q. A helicopter of mass $1000 k g$ rises with a vertical acceleration of $15 m s^{- 2} .$ The crew and the passengers weigh $300 k g$ . The magnitude of the action of the rotor of the helicopter on the surrounding air is

$2 \times 1 0^{3} N$

$3.25 \times 1 0^{4} N$

$3.5 \times 1 0^{4} N$

$7.5 \times 1 0^{3} N$

The required action is equal and opposite to the force on the helicopter due to the surrounding air.
$F - m g = ma$
$F = m (g + a)$
$= (1000] k g + 300 k g) (10 m s^{- 2} + 15 m s^{- 2})$
$= (1300) (25) N = 3.25 \times 1 0^{4} N$

Q. A helicopter of mass 1000kg rises with a vertical acceleration of 15ms−2. The crew and the passengers weigh 300kg. The magnitude of the action of the rotor of the helicopter on the surrounding air is

2×103N

3.25×104N

3.5×104N

7.5×103N