Title THIN LENSES SCHEME.pdf ✅

www.teachersofphysics.com Copyright © 2020 When the object is placed; i. between F and C ii. at C iii. beyond C iv. at infinity (ii) Virtual images (1 mark)  When the object is placed between F and the lens 7. State one application of a convex lens where the object is positioned between principal focus and the center of curvature (1 mark) i. Simple microscope ii. Compound microscope iii. In the camera 8. Sketch on a diagram to illustrate how a convex lens is used as a magnifying glass. (3 marks) 9. An object is placed at 2F in front of a converging lens and its image is observed. State how the image changes as the object is moved from 2F towards F.  At 2F the image formed is same size as the object as the object is moved towards F the image increases in size as it moves away from 2F to a max image formed at infinity when the object is at F 10. Show that the linear magnification M of a convex lens is given by
www.teachersofphysics.com Copyright © 2020  1 f V M (2 marks) We have; Multiply both sides by \v; But, , therefore, Re-arranging; 11. Describe with the aid of labeled diagram an experiment to determine the focal length of the lens when provided with the following; an illuminated object, a convex lens, a lens holder, a plane mirror and a meter rule. Cross wire (a) f (b) Image of the cross wire  Adjust the position of the object until a sharp image of the cross wire is formed alongside (close to) the object cross wire as shown in (b) above. The distance between the object and the center of the lens gives the focal length f of the lens. 12. You are provided with a meter rule, distant object, concave mirror and a white screen. Briefly describe how you can estimate the focal length of the focal length of the concave mirror. (3 marks) Focusing A Distant Object Apparatus Meter rule, lens, a lens holder, screen Procedure