(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

I have this problem, but not solutions, and my answer looks wrong but I can't really see that I've done anything wrong. So I was wondering if someone could check:

A transport plane travelling directly at a steady speed of 50m/s at an altitude of 300m releases a parcel when directly above a point X on level ground. Calculate:

a) The time of flight of the parcel

b) the speed of impact of the parcel

c) the distance from X to the point of impact

(all assuming g = 9.8m/s^2

2. The attempt at a solution

So I drew a diagram. For a) i got:

x = 300m, a = -9.8m/s^2, u = o, t = ?

[tex]300 = \frac{1}{2}(-9.8)t^{2}[/tex]

=> t = 7.82s

b) I got x = 300m, a = -9.8m/s^2, u = 0, v = ?

[tex]v^{2} = 0 + 2(-9.8)(300) \Rightarrow v = 54.2 m/s[/tex]

c) [tex]x_{h} = 7.82 * 50 = 391 m[/tex]

Now what I'm not sure about is did I do that correctly? and can I assume that initial velocity (u) is 0? And then the equations, they require me taking a square root of a negative number (which I can't do over the real number field) so can I modulate the number, or am I doing something wrong?

Also, could anyone recommend a good projectile motion / applications of newton's laws problem solving tutorial on the net? I can't seem to find one :(

Thanks!

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# Homework Help: Projectile Motion Check + Good tutorial?

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