A plano-convex lens has a thickness of 4 cm. When placed on a horiz. table , with the curved surface in contact with it , the apparent depth of the bottom most pt. of the lens is found to be 3 cm. If the lens is inverted such that the the table , the apparent depth of the centre of the plane face of the lens is found to be 25/8 cm. Find the focal length of the lens.
I m gettin the ans 75 cm while the ans given is 72 cm and 75 cm.... can som1 explain how the ans can be 72 also??
A plano-convex lens has a thickness of 4 cm. When placed on a horiz. table , with the curved surface in contact with it , the apparent depth of the bottom most pt. of the lens is found to be 3 cm. If the lens is inverted such that the the table , the apparent depth of the centre of the plane face of the lens is found to be 25/8 cm. Find the focal length of the lens.
I m gettin the ans 75 cm
while the ans given is 72 cm and 75 cm....
can som1 explain how the ans can be 72 also??
Radhika Batra , 11 Years ago
Grade 11
