A plano-convex lens \( P \) and a concavo-convex lens \( Q \) are in contact as shown in figure....
A plano-convex lens \( P \) and a concavo-convex lens \( Q \) are in contact as shown in figure. The refractive index of the material of the lens \( P \) and \( Q \) is \( 1.8 \) and \( 1.2 \) respectively. The radius of curvature of the concave surface of the lens \( Q \) is double the radius of curvature of the convex surface. The convex surface of \( Q \) is silvered.
An object is placed on the principal axis at a distance \( 10 \mathrm{~cm} \) from the plane surface. The image is formed at a distance \( 40 \mathrm{~cm} \) from the plane surface on the same side. The focal length of the system is
(a) \( -8 \mathrm{~cm} \)
(b) \( 8 \mathrm{~cm} \)
(c) \( -\frac{40}{3} \mathrm{~cm} \)
(d) \( \frac{40}{3} \mathrm{~cm} \)
📲PW App Link - https://bit.ly/YTAI_PWAP
🌐PW Website - https://www.pw.live