A 7900- helicopter accelerates upward at 0.90 while lifting a 1100- frame at a construction site.

A) What is the lift force exerted by the air on the helicopter rotors?
B)What is the tension in the cable (ignore its mass) that connects the frame to the helicopter?
C)What force does the cable exert on the helicopter

1 answer

m*a = Liftforce - m*g

In this case m is the combined mass of the helicopter and frame,

so

9000*0.9 = Liftforce - 9000*g

Solve for lift force

B) Drawing a free body diagram on the frame:

T - mg = m*a

T - 1100*9.8 = 1100*0.9

Solve for T

C) Drawing a free body diagram on the helicopter:

Liftforce - 7900*g - F(cable) = 7900*a