It really depends on your relationship and her personality.
I have a friend who I can talk about anything with, and she's pretty offbeat and open. And I thought she'd be a good fit for camming, so I messaged her and said "How do you feel about being on camera naked?" and she replied, "Is this because you want to see me naked or is it hypothetical?" and I said "I just started camming and I thought that you'd be great at it."
Turns out she's currently stripping (she lives in a different state, and we don't talk that often), so she's good on the job front, but she wasn't offended or shocked in the least.