Momentarily

The train is stopped and they announce
That we will be delayed
And momentarily we'll move;
We're stuck here, I'm afraid.

But "momentarily" is vague.
Exactly, what's it mean?
A minute, half an hour
Or some number in between?

The passengers start tapping feet
But no one says a word.
Compared to rants or raves, I guess,
The silence is preferred.

Then suddenly, ten minutes in,
The train begins to move
And builds up speed quite quickly,
Like there's something it must prove.

We're prisoners when we commute
And we must serve our time, 
A perfect opportunity
To write a little rhyme.