A diverging lens of focal length 30cm produces an image 20cm from the lens. Determine the object distance

in the image above, an incident ray XY makes an angle of 15\( ^{\circ} \) with a fixed line AY which is normal to surface of a plane mirror if the mirroe is turned as indicated by the arrow through \( 40^{\circ} \) what angle will the reflected ray make with AY

the arrow represents an object in front of a convex mirror whose focal points are X and Y. The image formed is

In the diagram above, which of the angles \( \theta _1 \) , \( \theta _2 \) , \( \theta _3 \) and \( \theta _4 \) is the angle of deviation of the ray of light passing through the glass prism XYZ?

Which of the following pairs of light rays shows the widest separation in the spectrum of white light?