Convex Lens Focal Length
 1) The effective diameter of the spherical outline of a convex lens is called Pole Focal length Curvature Aperture

 2) Select correct option related to virtual image? Inverted, virtual image is formed by the imaginary intersection of light rays and convex lens can form virtual image. Erect, virtual image is formed by the imaginary intersection of light rays and convex lens can form virtual image. Erect, virtual image is formed by the imaginary intersection of light rays and convex lens cannot form a virtual image. Erect, virtual image is formed by the actual intersection of light rays and convex lens can form virtual image.

 3) Four convex lenses had the same aperture. Which of the following convex lenses has more convergence? Convex lens of focal length 10 cm Convex lens of focal length 15cm Convex lens of focal length 12 cm Convex lens of focal length 9 cm

 4) Student 1 starts measurement from object. Student 2 starts measurement from the optical centre. Which of the following options is correct? Both are correct Both are incorrect Student 1 is correct Student 2 is correct

 5) The two spherical surfaces of a lens form part of a sphere. The centres of these spheres are called Centroid Centres of curvature Circumcentre Optical centre

 6) The bending of light when it passes from one medium to another under oblique incidence is Reflection Refraction Dispersion Diffraction

 7) The focal length of a lens is 20 cm. Its power is -5D +2D -2D +5D

 8) The focal length of 3 lenses is 15cm,10 cm and 20 cm respectively. Which of the following lens has more power? Lens of focal length =20cm Lens of focal length =15cm All lenses have equal power Lens of focal length =10 cm

 9) Object is placed on the left side of the lens. Image is formed on the left side of lens. Which of the following options is correct? u-distance from object to optical centre v- -distance from object to optical centre u and v are negative u is positive, and v is negative u is negative, and v is positive u and v are positive

 10) Power of 2 convex lenses are 0.25 and 0.5. What is the power of convex lens which is combination of these 2 lenses? 0.2 None of these 0.75 0.18

 11) A peephole on doors uses Convex lens Concave mirror Convex mirror Concave lens

 12) Select the incorrect statement on refractive index It is related to the speed of light in different media Refractive index of the second medium with respect to the first medium is the ratio of the sine of the incident angle to the sine of the refracted angle It indicates the extent of the change in direction of light that takes place in a given pair of media Refractive index of a lens changes with its shape

 13) Select the incorrect statement on refraction. It is the optical phenomenon involved when light rays fall on a mirror It is the phenomenon of bending of light when it travels from one medium to another It is the optical phenomenon involved when light rays pass through a lens It implies light does not travel in the same direction in all media

 14) Which of the following is not included in the precautions of a convex lens experiment? The eye should be placed atleast 25cm from the image formed by the convex lens on the screen Light rays from a distant object should fall on the lens without any obstruction Aperture of the convex lens should be large Convex lens should be thin and of good quality transparent glass