A thin converging lens of focal length f=25.0 cm forms the image of an object,on the screen,at a distance 5m from the lens. The screen is then drawn closer by a distance of 18cm. By what distance should the object be shifted so that its image on the screen is sharp again?

A thin converging lens of focal length 25.0cmforms the image of an object, on the screen, at a distance 5m from the lens. The screen is then drawn closer by a distance of 18cm. By what distance should the object be shifted so that its image on the screen is sharp again?

A thin converging lens of focal length f = 25 cm forms the image of an object on a screen placed at a distance of 75 cm from the lens. Now the screen in moved closer to the lens by a distance of 25 cm. The distance through which the object has to be shifted so that its image on the screen is sharp again is

A thin converging lens with focal length f = 25 cm projects the image of an object on a screen removed from the lens by a distance l == 5.0 m . Then the screen was draws closer to the lens by a distance Delta l = 18 cm . By what distance should the object be shifted for its image to become sharp again ?

A converging lens has a focal length of 0.12 m. To get an image of unit magnification the object should be placed at what distance from the converging lens ?

A convex lens of focal length 30 cm forms a real image three times larger than the object on a screen. Object and screen are moved until the image becomes twice the size of the object. If the shift of the object is 6 cm. The shift of screen is

A convex lens forms a real image on a screen placed at a distance 60 cm from the object. When the lens is shifted towards the screen by 20 cm , another image of the object is formed on the screen. The focal length of the lens is :