Suppose I roll a ball (without friction) down the passage and up a ramp at the end. If I release the ball with speed $v$ it acquires kinetic energy $T = (1/2) M v^2$ and, by conservation of energy. when it reaches the ramp it rises to a height $ h = T/Mg = (1/2g)(v_{initial}^2 - v_{final}^2 )$ where $v_{final} = 0$ .So far so good.
Putting some numbers into this, I impart a speed of $2 m/s$ and $g = 9.81 m/s^2$. Then the ball will rise up approximately $h = 0.2m$ on the ramp.
What I didn't mention is that I am actually doing this in a train (if trains were good enough for Einstein then they're good enough for me). I'm rolling the ball in the forward direction and the train is moving at $20$ m/s. So now when I calculate the rise I get $ h = (1/2g)(22^2 - 20^2 ) = 4.81m$
I can see that I probably need to impart more energy to the ball to accelerate it from $20 $ to $ 22 m/s$ than from $0 $ to $ 2$. What bothers me is that this seems to contradict the equivalence of inertial frames, and the speeds involved are hardly relativistic.
Problem solved here: https://physics.stackexchange.com/q/315526