Answer:
The marble was moving in a projectile and the speed of the engine was 2.716 m/s
Explanation:
The vertical component of the marble's flight path relative to the train
is given by the equation y(t) = v*t - (4.9)*t^2,
where, v is the initial upward velocity of the marble relative to the train.
So with y(1) = v - 4.9 = 0 we have
v = 4.9 m/s.
The marble will reach maximum height after 0.5 seconds, at which the
height will be y(0.5) = (4.9)*(0.5) - (4.9)*(0.5)^2 = (4.9)*(0.25) = 1.225 m.
Now, the marble has a vertical velocity component of 4.9 m/s and a horizontal velocity component
of V m/s such that tan(61) = 4.9 / V
V = 4.9 / tan(61) = 2.716 m/s
This horizontal velocity component of the marble is the same as the
speed of the train i.e. 2.716 m/s.
