Finding image location with concave mirror

physiquephys

1. The problem statement, all variables and given/known data
A small object is located 32.0cm in front of a concave mirror with a radius of curvature of 40.9cm.
Where will the image be formed?


2. Relevant equations

tan(θ)=-h/di
f=1/2R?

3. The attempt at a solution

Haven't been able to solve for theta. I'm not sure what equation to use, but I'm guessing that the radius is important. Do I need to find the focal length?

Redbelly98

Welcome to Physics Forums.

Yes, you need to find the focal length first. And, your text book should have a formula that relates focal length to the positions of the object and image, that will be helpful here.

Emilyjoint

you do need to know the focal length. You have to be careful with equations. focal length =R/2 not....1/2R....do you see what I mean/

physiquephys

Ohhhh, I see. I use 1/do + 1/di = 2/R (which is the focal point, & the reason the difference is indicated). Thank you both!

Redbelly98

Yes, that's the idea. You're welcome!