Physics
On reducing the focal length of a lens, its power :
- decreases
- increases
- does not change
- first increases then decreases.
Related Questions
The numerical value of magnification m is always …………… for a concave lens.
- equal to 1
- less than 1
- more than 1
- variable
If a lens deviates a ray towards its centre, its power is …………… and if it deviates the ray away from its centre, its power is ……………
- positive, positive
- negative, negative
- negative, positive
- positive, negative
The lens of power + 1.0 D is:
- convex of focal length 1.0 cm
- convex of focal length 1.0 m
- concave of focal length 1.0 cm
- concave of focal length 1.0 m.