An object approaches a convergent lens from the left of the lens with a uniform speed $$5 \mathrm{~m} / \mathrm{s}$$ and stops at the focus, the image
The refracting angle of prism is $$A$$ and refractive index of material of prism is $$\cot \frac{A}{2}$$. The angle of minimum deviation is $$A$$
The following figure shows a beam of light converging at point $$P$$. When a concave lens of focal length $$16 \mathrm{~cm}$$ is introduced in the path of the beam at a place shown by dotted line such that $$O P$$ becomes the axis of the lens, the beam converges at a distance $$x$$ from the lens. The value of $$x$$ will be equal to
Three polaroid sheets $$P_1, P_2$$ and $$P_3$$ are kept parallel to each other such that the angle between pass axes of $$P_1$$ and $$P_2$$ is $$45^{\circ}$$ and that between $$P_2$$ and $$P_3$$ is $$45^{\circ}$$. If unpolarised beam of light of intensity $$128 \mathrm{~Wm}^{-2}$$ is incident on $$P_1$$. What is the intensity of light oming out of $$P_3$$ ?