In spherical lenses, all distance are measured from ___________.

According to Cartesian sign conventions all distances are measured from the __________.

In case of spherical mirrors, all distances are measured from………. .

The image formation by spherical lenses is due to the phenomenon of _________.

The statements associated with a lens are given by the new cartesian symbol. Write the correct one All distance are measured from the focus. All distances measured along the direction of incident light is positive. Light ray is assumed to travel from right to left. X- axis is taken as the origin.

Contact lenses are made from

All the distances are measured from the ………….. Of the lens.