Net downward force on helicopter = Weight – Tension = mass * acceleration
Since the speed of the helicopter is decreasing, the acceleration is -0.98 m/s^2
m * 9.8 – T = m * -0.98 = -m * 0.98
Add T + m * 0.98 to both sides
m * 9.8 + m * 0.98 = T
Tension = m * 10.78
The tension is greater than the weight of the truck.
B) As the truck gets closer to the deck, the helicopter stops moving downward. While it hovers, it lets out the cable so that the truck is still moving downward. If the truck’s downward speed is decreasing at a rate of 0.10g, while the helicopter is at rest, what is the tension in the cable?
The truck still has 2 vertical forces on it. The tension in the cable is still the upward force, and its weight is still a downward force. And the truck is still decelerating at the rate of 0.98 m/s 2. Since the mass, weight, and negative acceleration of the truck are the same as before the helicopter, the tension in the cable is still m * 10.78.
The truck did not feel a thing when the helicopter stopped!
And the mass of the helicopter has no affect on the truck!