Solving Lens Image Problem: Where is Image Formed?

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The discussion focuses on calculating the image distance for an object in front of a convex mirror. The initial calculation using the formula Di = (Doxf)/(Do+f) yielded an incorrect image distance of 5.23 cm instead of the expected 3.41 cm. The focal length for the convex mirror was correctly identified as 4.9 cm, derived from the radius of curvature. The user initially questioned the relevance of the object's height in the calculations but later resolved the issue independently. The thread highlights the importance of accurately applying the mirror formula and understanding the properties of convex mirrors.
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An object 1.95 cm high is placed 11.2 cm in front of a convex mirror with a radius of curvature of 9.8 cm. Where is the image formed??

So i know Di= (Doxf)/(Do+f)...(11.2 x 9.8)/ (11.2 + 9.8) = 5.23 cm

However, the correct answer is 3.41 cm

What am i doing wrong here? I know that the 9.8 may not be the focal length but how do i relate the height to the focal length??
 
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Focal length of the convex mirror = R/2 = 9.8/2 = 4.9 cm.
 
do i even need to use the height of the object??...if so how?
 
nevermind i got it! thanks!
 
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