Optical Instruments

A. center of curvature
B. focus
C. optical center
D. aperture

A. 10 dioptre
B. 10 dioptre
C. 1 / 10 dioptre
D. 1 / 10 dioptre

A. 2 f
B. 2.5 f
C. 3f
D. 4f

A. between principal focus and center of curvature
B. beyond 2 f
C. at the principal focus
D. between principal focus and optical center

A. 0.5
B. 0.2
C. 1
D. 2

A. increases with increase in age
B. decreases with increase in age
C. neither increases nor decreases
D. becomes infinite after 60 years

A. zero
B. focus
C. 2 f
D. f/2

A. fo + fe
B. fo – fe
C. fo / fe
D. fe / fo

A. real and inverted
B. real and erect
C. virtual and erect
D. virtual and inverted

A. same
B. different
C. zero
D. different with refractive index of core higher than cladding