Define the magnifying power of a compound microscope when the final im

1.	Define the magnifying power of a compound microscope when the final image is formed at infinity. Why must both the objective and the eyepiece of a compound microscope has short focal lengths? Explain.
Answer» Magnifying power is defined as the angle subtended at the eye by the image to the angle subtended (at the unaided eye) by the object. (Alternatively: Also accept this definition in the form of formula) \(m=m_o \times m_e = \frac{L}{f_o}\times\frac{D}{f_e}\) To increase the magnifying power both the objective and eyepiece must have short focal lengths (as \(m=\frac{L}{f_o}\times \frac{D}{f_e}\))

Define the magnifying power of a compound microscope when the final image is formed at infinity. Why must both the objective and the eyepiece of a compound microscope has short focal lengths? Explain.

Answer»

Magnifying power is defined as the angle subtended at the eye by the image to the angle subtended (at the unaided eye) by the object.

(Alternatively: Also accept this definition in the form of formula)

\(m=m_o \times m_e = \frac{L}{f_o}\times\frac{D}{f_e}\)

To increase the magnifying power both the objective and eyepiece must have short focal lengths (as \(m=\frac{L}{f_o}\times \frac{D}{f_e}\))