Q. A 140-g ball collides elastically with a 310-g ball that is at rest. If the 140-g ball was travelling in positive x-direction at 4.75m/s before the impact, what are velocities of the two balls after the impact?
Q. A magnifying glass has a converging lens of focal length of 18.80cm. At what distance from a nickel must you hold this lens to get an image with a magnification of +2.47?