In an experiment to measure the focal length (f) of a convex lens, the magnitude of object distance (x) and the image distance (y) are measured with reference to the focal point of the lens. The y-x plot is shown in figure. The focal length of the lens i $s_____cm.$

Question

G1 Physics · Accepted Answer

Image From the graph, one convenient point gives: x = 20 cm y = 20 cm Using Newton’s lens formula: xy = f² 20 × 20 = f² Therefore, f = 20 cm

In an experiment to measure the focal length (f) of a convex lens, the magnitude of object distance (x) and the image distance (y) are measured with reference to the focal point of the lens. The y-x plot is shown in figure. The focal length of the lens i s_____cm.