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

Given a missile with 9500km range, what must its initial velocity be to travel that distance? Disregard issues introduced by the missile's boost phase, and state the velocity as km/h.

(Presumably, the curvature of the planet is to be ignored, as well.)

2. Relevant equations

Unsure; see below.

3. The attempt at a solution

If a missile is to have maximum range, then its launch angle ought to be 45°. It would also have a symmetrical trajectory and is affected by gravity at -9.8 m/s^2 (or 0.0098 km/s^2 in the terms of this problem).

The first thing that came to mind was to use R=Vo^2/g*sin(2*45) and solve for Vo, but that yielded something ridiculously slow for that long of travel.

I'm rather unsure as to which equation(s) ought to be used to solve such a problem, since everything I can find written in my notes refers to what appear to be slightly different situations.

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# Homework Help: Given range and angle - but not time - find initial velocity?

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