A slide projector gives magnification of 10. If it projects a slide of 3 cm `xx` 2 cm on a screen, the area of image on screen is :

A slide projector gives a magnification of 10. If a slide of dimensions 3 cm xx 2 cm is projected on the screen, the area of the image on the screen is :

A projector lens has a focal length of 10 cm. It produces a real image of a 2cm xx 2 cm slide on a screen 5 metre from the lens. What is the size of the picture on the screen ?

A slide projector has to project a 35 mm slide (35 mm xx 23 mm) on a 2 m xx 2m screen at a distance of 10 m from the lens. What should be the focal length of the lens in the projector ?

A slide projector has to project a 35 mm slide (35 mm xx 23 mm) on a 2 m xx 2m screen at a distance of 10 m from the lens. What should be the focal length of the lens in the projector ?

A slide projector has to project a 35 mm slide (35 mm xx 23 mm) on a 2 m xx 2m screen at a distance of 10 m from the lens. What should be the focal length of the lens in the projector ?

A convex lens produces an image of a real object on a screen with a magnification of 1/2. When the lens is moved 30 cm away from the object, the magnification of the image on the screen is 2. The focal length of the lens is

A convex lens produces an image of a real object on a screen with a magnification of 1/2. When the lens is moved 30 cm away from the object, the magnification of the image on the screen is 2. The focal length of the lens is