A helicopter of mass M is lowering a truck of mass m onto the deck of a ship. In first case the helicopter and the truck move downward together (the length of the cable remains constant.). Tension in

Question

A helicopter of mass M is lowering a truck of mass m onto the deck of a ship. In first case the helicopter and the truck move downward together (the length of the cable remains constant.). Tension in the cable is $T_{1}$ when their downward speed is decreasing at a rate of $\frac{g}{10}$ . In second case when the truck gets close to the deck, the helicopter stops moving downward. While it hovers stationary, it lets out the cable so that the truck is still moving downward. If the truck is moving downward with a speed decreasing at rate of $\frac{g}{10}$ , tension in string is now $T_{2}$ . What is ratio $T_{1} / T_{2}$ .

Options:

Answer:

C

Solution:

In both cases the truck of mass $m$ moves downward with its speed decreasing at $g /10$ , so its acceleration is $g /10$ upward.

$T - m g = m \frac{g}{10} \Rightarrow T = \frac{11}{10} m g$ in both cases, so $T_{1} = T_{2}$ .

$T_{1} / T_{2} = 1$ .

TestHub · Accepted Answer

In both cases the truck of mass m moves downward with its speed decreasing at g /10 , so its acceleration is g /10 upward. T − m g = m 10 g ​ ⇒ T = 10 11 ​ m g in both cases, so T 1 ​ = T 2 ​ . T 1 ​ / T 2 ​ = 1 .

Physics - NLM Question with Solution | TestHub

Options:

Doubts & Discussion