Lighting, Light Fixtures, Ceiling and Exhaust Fans - Basement light with a whip

I am going to hang a new heavier light in basement. I plan to connect to existing box with a whip. There are three wires coming from box. Two white that were twisted together and a yellow one. This box is also connected to a switch. I can't hang light directly over box because there is conduit etc in the way.
I plan on purchasing a cover for box, a whip, connectors and some cable clips. Is there anything I need to watch out for when attempting this? any tips?

I bought the whip, it has three wires. Fixture only has two, box has two also (to white together and yellow one). What do I do with extra wire?

Are you in Chicago by any chance?

What color are the wires on the "whip"? Actually I'm not familiar with the term whip at all. When someone starts talking about whips in their basement I usually steer clear. ;)

If the colors are black/white/green, the "extra" green wire is your ground, and you need to connect this to your bare grounds (if you have them) or the grounding screw in the ceiling box.

If black/white/red then this is a different case. But again I do not know what a whip is as it relates to lighting.

Yes, I am close to Chicago. The package I bought says ready to install 14-3, 6ft Lighting fixture whip. It has three wires - green, black and white.

Black to yellow, white to white, green gets grounded as I mentioned before.

Ah, and I see you've just filled in your location. Always a good idea.

A whip is a term I am familiar with in the A/C trade.
It is a pre-assembled length of flexible conduit and conductors.

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