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Please help me.. I am desperate!!! please show me your all work please.....

1. (a) what is the accleration of two falling sky divers (mass 120 kg including parachute) when the upward force of air resistance is equal to one fourth of their wight? (b) After popping open the parachute, the divers descend leisurely to the ground at constant speed. What now is the force of air resistance on the sky divers and their parachute?

2. A 6500 kg helicopter accelerates upward at 0.60 m/s^2 while lifting a 1200 kg car (a) what is the lift force exerted by the air on the rotors? (b) What is the tension in the cable (ignore its mass) that connects the car to the helicopter?

3. A person pushes a 14.5kg lawn mower at constant speed with a force of 88 N directed along the handle, which is at an angle of 45 to the horizontal. (a) Draw the free body diagram showing all forces acting on the mower, then (c) the normal force exerted vertically upward on the mower by the ground, and (b) the force the person must exert on the lawn mower to accelerate it from rest to 1.5 m/s in 2.5 seconds (assuming the same retarding force).

4. A 6500 kg helicopter acclerates upward at 0.60 m/s^2 while lifting a 1200 kg car. (a) What is the lift force exerted by the air on the rotors? (b) What is the tension in the cable that connects the car to the helicopter?

By Physicskid123 (Physicskid123) on Wednesday, October 06, 2004 - 07:35 pm: Edit

Just draw free body diagrams and use sum of all F=MA. Should get the answers no problem.