282834 The two lenses of an achromatic doublet should have

282835 The dispersive powers of the materials of two lenses forming an achromatic combination are in the ratio of \(4: 3\). Effective focal length of the two lenses is \(+60 \mathrm{~cm}\) then the focal lengths of the lenses should be

282836 A thin converging lens of focal length \(f=25 \mathrm{~cm}\) forms the image of an object on a screen placed at a distance of \(75 \mathrm{~cm}\) from the lens. The screen is 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 in sharp again is

282837 If the wavelengths of light used in an optical instrument are \(\lambda_1=4000 \AA\) and \(\lambda_2=5000 \AA\), then ratio of their respective resolving powers (corresponding to \(\lambda_1\) and \(\lambda_2\) ) is

282834 The two lenses of an achromatic doublet should have

282835 The dispersive powers of the materials of two lenses forming an achromatic combination are in the ratio of \(4: 3\). Effective focal length of the two lenses is \(+60 \mathrm{~cm}\) then the focal lengths of the lenses should be

282836 A thin converging lens of focal length \(f=25 \mathrm{~cm}\) forms the image of an object on a screen placed at a distance of \(75 \mathrm{~cm}\) from the lens. The screen is 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 in sharp again is

282837 If the wavelengths of light used in an optical instrument are \(\lambda_1=4000 \AA\) and \(\lambda_2=5000 \AA\), then ratio of their respective resolving powers (corresponding to \(\lambda_1\) and \(\lambda_2\) ) is

282834 The two lenses of an achromatic doublet should have

282835 The dispersive powers of the materials of two lenses forming an achromatic combination are in the ratio of \(4: 3\). Effective focal length of the two lenses is \(+60 \mathrm{~cm}\) then the focal lengths of the lenses should be

282836 A thin converging lens of focal length \(f=25 \mathrm{~cm}\) forms the image of an object on a screen placed at a distance of \(75 \mathrm{~cm}\) from the lens. The screen is 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 in sharp again is

282837 If the wavelengths of light used in an optical instrument are \(\lambda_1=4000 \AA\) and \(\lambda_2=5000 \AA\), then ratio of their respective resolving powers (corresponding to \(\lambda_1\) and \(\lambda_2\) ) is

282834 The two lenses of an achromatic doublet should have

282835 The dispersive powers of the materials of two lenses forming an achromatic combination are in the ratio of \(4: 3\). Effective focal length of the two lenses is \(+60 \mathrm{~cm}\) then the focal lengths of the lenses should be

282836 A thin converging lens of focal length \(f=25 \mathrm{~cm}\) forms the image of an object on a screen placed at a distance of \(75 \mathrm{~cm}\) from the lens. The screen is 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 in sharp again is

282837 If the wavelengths of light used in an optical instrument are \(\lambda_1=4000 \AA\) and \(\lambda_2=5000 \AA\), then ratio of their respective resolving powers (corresponding to \(\lambda_1\) and \(\lambda_2\) ) is