power of alens combination of two concave lenses is -6D.If the focal length of one of them is 25cm.,what will be the focal length of the other in cm,?
+26402 Power of a lens combination of two concave lenses is -6D.
If the focal length of one of them is 25cm,
what will be the focal length of the other in cm ?
$$D_1 + D_2 = -6\ dpt \quad | \quad \boxed{D = \dfrac{1}{f}} \quad f = \mathrm{focal}\ \mathrm{length}\ \mathrm{in} \ \mathrm{m} \\\\
f_1 = 0.25\ \mathrm{m}\qquad
D_1 = -\dfrac{1}{0.25\ \mathrm{m}} \quad \small{\text{ Negatively there concave lens}}\\\\
D_1 = -4\ dpt \\\\
D_2 = -6\ dpt - D_1 = -6\ dpt + 4\ dpt = -2\ dpt\\\\
f_2 = -\dfrac{1}{D_2}\ \mathrm{m} = \dfrac{1}{2}\ \mathrm{m} = 50\ \mathrm{cm}$$
+26402 Power of a lens combination of two concave lenses is -6D.
If the focal length of one of them is 25cm,
what will be the focal length of the other in cm ?
$$D_1 + D_2 = -6\ dpt \quad | \quad \boxed{D = \dfrac{1}{f}} \quad f = \mathrm{focal}\ \mathrm{length}\ \mathrm{in} \ \mathrm{m} \\\\
f_1 = 0.25\ \mathrm{m}\qquad
D_1 = -\dfrac{1}{0.25\ \mathrm{m}} \quad \small{\text{ Negatively there concave lens}}\\\\
D_1 = -4\ dpt \\\\
D_2 = -6\ dpt - D_1 = -6\ dpt + 4\ dpt = -2\ dpt\\\\
f_2 = -\dfrac{1}{D_2}\ \mathrm{m} = \dfrac{1}{2}\ \mathrm{m} = 50\ \mathrm{cm}$$
