Path of a projectile traveling along a meridian of the earth

chaoseverlasting
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Homework Statement


I've been working out an example by myself from the book Adv. Engg. Mathematics, E.Kreszig, section 8.7 p441.

The path of a projectile traveling along a meridian of the Earth uniformly may be given by
\vec{r(t)}=Rcos\gamma t\vec{b} + Rsin\gamma t\vec{k} where i,j,k are unit vectors along x,y,z axes respectively.

The vector \vec{b} is defined as \vec{b}=cos\omega t\vec{i} +sin\omega t\vec{j}

Differentiating \vec{r(t)} twice to get the expression for acceleration. This comes out to be

\vec{a(t)}=-R(\gamma ^2+\omega ^2)cos(\gamma t)\vec{b} -2R\gamma sin(\gamma t)\vec{b'} - R\gamma ^2cos(\gamma t)\vec{k}.

The first term is the centripital acceleration due to the Earth and the path of the projectile, the second is the coriolis acceleration. What is the third term?
 
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It is the z component of the centripetal acceleration.
It should have sin\gamma t.
 
Oh. ! thank you. That was incredibly stupid of me.
 
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