In a glass \((\mu = 1.5)\) sphere with a radius of \(10​​\text{cm},\) there is an air bubble \(B\) at a distance of \(5​​\text{cm}\) from \(C.\) The distance of the bubble from the surface of the sphere (i.e., point \(A\)) as observed from the point \(P\) in the air will be:

            

1.	\(4.5​​\text{cm}\)	2.	\(20.0​​\text{cm}\)
3.	\(9.37​​\text{cm}\)	4.	\(6.67​​\text{cm}\)

A lens forms an image of a point object placed at distance \(20~\text{cm}\) from it. The image is formed just in front of the object at a distance \(4~\text{cm}\) from the object (and towards the lens). The power of the lens is:
1. \(-2.25~\text D\) 
2. \(1.75~\text D\) 
3. \(-1.25~\text D\) 
4. \(1.4~\text D\) 

The distance between the object and its real image formed by a concave mirror is minimum when the distance of the object from the center of curvature of the mirror is: (where\(f\) is the focal length of the mirror)
1. zero
2. \(\dfrac{f}{2}\)
3. \(f\)
4. \(2f\)

A point object \(O\) is placed at a distance \(20\) cm from a biconvex lens of the radius of curvature \(20\) cm and \(\mu=1.5.\) The final image produced by lens and mirror combination will be at:

In the case of a compound microscope, the image formed by the objective lens is:

In the following diagram, what is the distance \(x\) if the radius of curvature is \(R= 15​​\text{cm}?\)

In the diagram shown below, the image of the point object \(O\) is formed at \(l\) by the convex lens of focal length \(20~\text{cm},\)  where \(F_1\) and \(F_2\) are foci of the lens. The value of \(x'\) is:
        

A glass slab is placed with the right-angled prism as shown in the figure. The possible value of \(\theta\) such that light incident normally on the prism does not pass through the glass slab is:

A graph is plotted between the angle of deviation \(\delta\) in a triangular prism and the angle of incidence as shown in the figure. Refracting angle of the prism is: