A 4500-kg helicopter accelerates upward at 2.0m/s squared. What lift force is exerted by the air on the propellers?
Please show work so i can understand.....thanks
2006-12-03 22:28:16 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Physics
I'll take a stab at this.
The helicopter needs enough lift force to counteract gravity in order for it to just stay at the same altitude. So at 0m/s² vertical acceleration, assuming that gravity is 9.81m/s², the rotors would need to produce 4,500kg x 9.8m/s² = 44,100N.
So to achieve a vertical acceleration of 2m/s², the rotors need to produce 4,500 x (9.81 + 2) = 53,145N of lift.
If the helicopter is climbing as well as moving forwards, then the rotors would need to produce proportionately more lift than this.
2006-12-03 22:48:15 · answer #1 · answered by k² 6 · 1⤊ 0⤋
here's my attempt at Physics...
we combine Newton's law of motion and gravitation:
F = m x g x a
therefore:
F = 4500 kg x 2 m/s(squared) x 9.8 m/s(squared)
F = 88,200 N (Joules)
so it takes 88,200 Joules to achive an acceleration of 2.0 m/s squared at an upward lift.
2006-12-04 06:58:22 · answer #2 · answered by Ricky the Kid 4 · 0⤊ 0⤋
k2 is correct. My physics teacher gave us the answer to the problem this morning.
2006-12-05 20:15:32 · answer #3 · answered by Jen 2 · 1⤊ 0⤋