Momentum: Person drops out of a Hanglider

[huynhtn2]

Homework Statement

A 10.1 m long glider with a mass of 666.0 kg (including the passengers) is gliding horizontally through the air at 28.9 m/s when a 57.0 kg skydiver drops out by releasing his grip on the glider. What is the glider's velocity just after the skydiver let's go?

Homework Equations

P= mv
F=dp/dt
dp=mdv

The Attempt at a Solution

P= mv
p=(666)(28.9)
= 19247.4 kg*m/s

P= mv
p/(666-57) = v2
31.60 m/s =v2

what did i do wrong?

 

[mugaliens]

What is the glider's velocity just after the skydiver let's go?

Hint question: Does the act of letting go of the glider impart any acceleration to the glider? If so (and here's the key), how long has that acceleration been acting on the glider? In other words, how long is "just after?" ;)

 

[huynhtn2]

Hint question: Does the act of letting go of the glider impart any acceleration to the glider? If so (and here's the key), how long has that acceleration been acting on the glider? In other words, how long is "just after?" ;)

I don't understand how letting go could accelerate the glider.