In a certain camera, a combination of four similar thin convex lenses are arranged axially in contact. Then the power of the combination and the total magnification in comparison to the power ($p$) and magnification ($m$) for each lens will be, respectively:

A $4p$ and $4m$

B $p^4$ and $4m$

C $4p$ and $m^4$

D $p^4$ and $m^4$

The answer is C.

Solution

Powers in contact add algebraically ($P = 4p$), while successive magnifications multiply ($M = m^4$).

When thin lenses are placed in contact, their focal powers add algebraically: $P = p_1 + p_2 + p_3 + p_4 = 4p$. For successive lenses, the total linear magnification is the product of individual magnifications: $M = m_1 \times m_2 \times m_3 \times m_4 = m^4$.

Concept Lens Combination Power and Magnification

Combination of Thin Lenses in Contact in past papers

2 questions from this chapter have appeared across 2 exam years.

In a certain camera, a combination of four similar thin convex lenses are arranged axially in contact. Then the power of the combination and the total magnification in comparison to the power ($p$) and magnification ($m$) for each lens will be, respectively:

Solution

Combination of Thin Lenses in Contact in past papers

Practice

Free resources

Platform

At the institute