A `12 m` tall tree is to be photographed with a pin hole camera. It is situated `15 m` away from the pin hole. How far should the screen be placed from the pin hole to obtain a `12 cm` tall image of the tree ?

A 12 m tall tree is to be photographed with a pin hole camera. It is situated 15 m away from the pin hole. How for should the screen be placed from the pin hole to obtain 12 cm tall image of the tree?

A 6 m tall tree is at a distance of 18 m from a pin hole camera. Where should a screen be placed to obtain a 20 cm tall image of the tree ?

A tree, which is 200 m away from the pinhole, produces an image of height 1 cm, in a pinhole camera of width 20 cm. Find the height of the tree.

A man 1.7 metres tall stands 10 metres away from the foot of a tree, and he sees the top of the tree at an angle of elevation 40^circ . How tall is the tree?

Light travels in a straight line. This principle is illustrated in a pinhole camera. In this simple device the image of an object is formed on a photographic plate by light passing through a small hole. In one experiment, 5 cm high image of a tree was obtained on a photo plate placed at a distance of 15 cm from the pin hole. Actual height of the tree is 20 m. (a) Find the distance of the pinhole from the tree. (b) How is the size of image affected if the photo plate is moved away from the pinhole? (c) What will happen if a large hole is made in place of a pin hole?

A 3 cm tall object is placed 18 cm in front of a concave mirror of focal length 12 cm. At what distance from the mirror should a screen be placed to see a sharp image of the object on the screen. Also calculate the height of the image formed.