Linear Magnification
Trending Questions
Q. The image of an object placed at a distance of 25 cm on the principal axis of a concave mirror from its pole, is formed on the object itself. Find out the linear magnification.
- -1
- 1
- -2
- 2
Q.
In the given figure, where do the diverging rays seem to meet?
(F1 , F2 are the primary focus of the lens)
F2
2F1
2F2
F1
Q. The distance between optical centre and is known as focal length of the lens.
- principal focus
- aperture
- centre of curvature
Q. The distance between optical centre and is known as focal length of the lens.
- centre of curvature
- aperture
- principal focus
Q. The parallel rays of light after passing through a convex lens converge at:
- Centre of curvature
- Optical centre
- Infinity
- Principal focus
Q. Why is a thin lens preferred over a thicker one?
- To increase the power of the lens.
- To avoid reflection of light.
- To avoid lateral displacement of the light ray.
- To remove wastage of glass.
Q. The distance between optical centre and is known as focal length of the lens.
- centre of curvature
- principal focus
- aperture
Q. A ray of light passing through a principal focus, after refraction from a convex lens ___.
- will emerge perpendicular to the principal axis
- will emerge parallel to the principal axis
- will emerge at an angle of 450 to the principal axis
- will emerge undeviated
Q. According to the sign convention, which of the following is true for focal lengths of convex and concave lenses?
Q. <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}-->
Focal length of a lens is twice the radius of curvature.
- True
- False
Q. The parallel rays of light after passing through a convex lens converge at:
- Principal focus
- Infinity
- Centre of curvature
- Optical centre
Q. A light ray passing through a spherical lens undergoes refractions.
- one
- four
- two
Q. A ray of light from the object, parallel to the principal axis, after refraction from a convex lens, passes through ___.
- the principal focus on the other side of the lens
- the centre of curvature on the other side of the lens
- the centre of curvature on the same side of the lens
- the principal focus on the same side of the lens
Q. <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}-->
Focal length of a lens is twice the radius of curvature.
- False
- True
Q.
Convex lens of very short focal length will make:
Lesser convergence of light rays
Lesser divergence of light rays
Higher divergence of light rays
Higher convergence of light rays
Q.
The smaller the focus of a convex lens more will be its magnifying capacity, so why don't we use magnifying glasses with very small focal length?
They would be too heavy.
They are difficult to manufacture.
The image will be too big for our liking.
One would have to hold the magnifying glass to close to the object.
Q. <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}-->
Focal length of a lens is twice the radius of curvature.
- True
- False
Q. Lenses have two radii of curvature, as they have two refracting curved surfaces.
- True
- False
Q. Lenses have two radii of curvature, as they have two refracting curved surfaces.
- False
- True
Q. Which lens should be used to burn a piece of paper?
- Plano-concave lens
- Biconvex lens
- Glass slab
- Biconcave lens
Q. Lenses have two radii of curvature, as they have two refracting curved surfaces.