How will 17:9 content look like on different aspect ratio displays?

[lsquare]

I'm not good at imagining how a video will be displayed on a screen. When watching a 17:9 video on 16:9, 16:10: and 21:9 screens, what would the black bars look like, and where it'll be?

[ac6000cw]

Normally, on a 16:9 screen - thin black bars top & bottom, on 16:10 screen - thicker bars top & bottom, on 21:9 screen - bars on left & right sides.