Tag: physics

When the reflecting or refracting rays do not actually intersect but appear to intersect when produced backwards, 

The image which can be obtained on a screen is called

A virtual image is

Comparing real and virtual images, we may say that

A real image is formed by

A real image is

A thin convex lens of focal length $30.00\ cm$ forms an image $2.00\ cm$ high, of an object at infinity. A thin concave lens of focal length $20.00\ cm$ is placed $26.00\ cm$ from the convex lens on the side of the image. The height of the image now is

A meter stick lies along the optic axis of a convex lens of focal length 40 cm its nearer end 60 cm from the mirror surface. How long is the image of stick?

When the distance between the object and the screen is more than 4f, we can obtain the image of the object on the screen for the two positions of the lens. It is called displacement method.In one case, the image is magnified. If $I _1$ and $I _2$ be the sizes of the two images, then the size of the object is

If $I _1$ and $I _2$ be the size of the images respectively for the two positions of lens in the displacement method, then the size of the object is given by