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

For a space-based platform B launching a projectile A what are the resultant inertial velocities equations and where do the launch location and projectile end up a little after launch? The platform is rotating and moving thru space and the launch mechanism imparts a fixed N*sec impulse to the projectile. The projectile is not located at the platform CG and the impulse does not act thru the platform CG.

2. Relevant equations

Ignore gravity, drag, and launcher friction

Impulse acts at projectile CG

mB = platform mass (mA for projectile)

PB = platform initial inertial position of CG (PA for projectile)

VB = platform initial inertial velocity of CG (VA for projectile)

wB = platform initial inertial rotation rate about its CG (wA for projectile)

IxxB = platform moment of inertia (IxxA for projectile)

F = applied impulse force to projectile at time zero

dt = time period after launch to calculate the launch and projectile location

R = distance vector from platform CG to launch location (i.e. projectile CG at launch)

3. The attempt at a solution

These are vectors...

Pre-launch:

VA = VB since they are attached

wA = wB since they are attached

R = PA - PB

After launch:

VB(t) = VB - F / mB this is a constant

PB(t) = PB + VB(t) t

wB(t) = wB - F x R / IxxB this is a constant

VA(t) = VA + F / mA + wB(t) x R this is a constant

PA(t) = PA + VA(t) t

R(t) = R rotated (wB(t) t)

Launch location: PL(t) = PB(t) + R(t)

Projectile location: PA(t)

4. Should I be including more of the parts shown inhttps://www.physicsforums.com/showthread.php?t=77434

aA = aB + wBdot x R + w x (w x R) + 2 w x VRel + aRel

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# Homework Help: Angular momentum when launching projectile

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