# Helicopter problem

#### Viper2838

This problem led to a debate in my physics class, which was never resolved.

A helicopter holding a 70kg package from a rope 5m long is accelerating up at a rate of 5.2 m/s^2. Neglect air resistance. When the upward velocity of the helicopter is 30 m/s, the rope is cut and the helicopter continues to rise at a rate of 5.2 m/s^2. Determine the distance between the helicopter and package after 2 seconds.

The debate was over whether or not the package had a velocity of 0 or 30m/s after it was cut. I personally believed the package to follow a projectile path upward at a starting velocity of 30 m/s. Am I wrong?

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#### mtong

In my opinion the package would have an upwards velocity on 30m/s and be accelerationg downwards at g.

#### Oerg

It is obvious that when the package starts falling it has an initial velocity of 30m/s, taking upwards as positive. Take for example a bus. If you are a passenger, and if the bus was travelling at a high speed and was forced to brake at a high deceleration, you would be flung forward because you are still travelling at the bus's initial velocity before the bus decelerates.

#### Knavish

Yup, no debate about it: it still has the velocity given to it by the helicopter, as they were acting as one object initially.

#### Viper2838

Thank you all for helping me on this one. I thought that the package should have an initial velocity of 30 m/s. Unfortunately, i was the only one to think so . Oh well. Thanks again

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