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Homework Statement
A train is moving counterclockwise with a constant speed of 10 m/s in a circle of radius ##\frac {16} π## m. The plane of the circle lies in the xy plane. At time t = 0, the train is at P, when a stone is thrown from it with a speed of 10 m/s relative to the train towards the negative ##x## axis at an angle of 37° with the vertical ##z## axis (assume g = 10 m/s^{2} and sin 37° = ##\frac 3 5##). Find:
(a) the velocity of the stone relative to the train at the highest point of its trajectory.
(b) the coordinates of the point where it finally falls.
(c) the coordinates of the point at the highest point of its trajectory.
Homework Equations
Let v_{ST} be the velocity vector of the stone relative to the train.
v_{ST} = u_{ST}  gt##\hat k##
Also, position vector r = u_{S}t  gt^{2}##\hat k##
The Attempt at a Solution
I know how to solve this problem, but there's just one hitch. The ##x## components of the velocity and coordinates they've given as the answer isn't matching with mine. Their answers are:
(a) (6##\hat i## + 10##\hat j##) m/s
(b) (4.5 m, 16 m, 0)
(c) (0.3 m, 8 m, 3.2 m)
Later, I found out that they haven't considered the centripetal acceleration (along the negative ##x## direction) that would be imparted to the stone at the instant of projection; due to the circular motion of the train. Why?
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