A man can see the objects upto a distance of one metre from his eyes. For correcting his eye sight so that he can see an object at infinity, he requires a lens whose power is

A man cannot see clearly the objects beyond a distance of 20 cm from his eyes. To see distant objects clearly he must use which kind of lenses and of what focal length

A boy can clearly see objects between distance 15 cm to 200 cm from his eye . To clearly see an object situated at infinity , what will be the power of the lens that should he use? If he wears that lens then what will be the least distance of distinct vision in that case?

A person can see the objects lying between 25 cm and 10 m from his eye. His vision can be corrected by using lens of power :

A man can see clearly up to 3 metres. Prescribes a lens for his spectacles so that he can see clearly up to 12 metres

A far sighted person cannot see object clearly al a distance less than 75 cm from his eyes. The power of the lens needed to read an object al 25 cm is

A far sighted person cannot see object clearly al a distance less than 75 cm from his eyes. The power of the lens needed to read an object al 25 cm is