Light Reflectio...

An object is placed at a distance of 1.5 m from a screen and a convex lens is interposed between them. The magnification produced is 4. The focal length of the lens is then

Refraction of light from air to glass and from air to water are shown in figure (i) and figure (ii) below. The value of the angle $$\theta$$ in the case of refraction as shown in figure (iii) will be 

A convex lens of focal length $$f$$ produces a real image $$\mu$$ times the size of an object, Then what is the distance of the object from the lens? 

The distance between an object and its doubly magnified image by a concave mirror is: [ Assume $$f$$ = focal length]

Refraction of the light from the air to glass and from air to water are shown in the figure (i) and figure (ii) below. The value of an angle $$\theta$$ in the case of refraction as shown in the figure (iii) will be

One face of a rectangular glass plate $$6{\text{ }}cm$$ thick is silvered. An object held $$8{\text{ }}cm$$ in front of the fist face, forms an image $$12{\text{ }}cm$$ behind the silvered face. The refractive index of the glass is:

A bulb is located on a wall. Its image is to be obtained on a parallel wall with the help of convex lens. If the distance between parallel walls is $$D$$ then required focal length of lens placed in middle between the walls is :

An object of length $$6\ cm$$ is placed on the principle axis of a concave mirror of focal length $$f$$ at a distance of $$4\ f$$. The length of the image will be

The magnification of plane mirror is always - 

An infinitely long rod lies along the axis of a concave mirror of focal length l. The near end of the rod is at distance u $$>$$ f from the mirror. Its image will have a length?