Answer:
v = 4.4 m / s
Explanation:
Unfortunately, the exercise scheme does not appear. Let's analyze the problem the marble leaves point A with an initial velocity, goes down and then rises to a given height where its velocity is zero, in the whole trajectory they tell us that the resistance is zero, so we can use the conservation relations of the enegy.
Starting point. Point A
Em₀ = K + U = ½ m v2 + mg y_a
point B.
Em_f = U = m g y
the energy is conserved
Em₀ = Em_f
½ m v² + mg y_a = m g y
½ m v² = m g (y -y_a)
v =
In the exercise the diagram is not seen, but the height of point A must be known, suppose that y_a = 4 m
v =
v = 4.4 m / s