Question

 A student is performing an experiment in physics laboratory to measure the focal length of a convex lens using the distant object method.​

Answer 1

Answer:

Solution

A convex lens always forms the image of a nearby object away from its focus. So, if a student obtained the image of the candle on the screen, that means the screen was away from the focus somewhere.

Now, if he needs to form an image of a distant lamp on the same screen then he needs to move the screen in the direction of the lens or the lens in the direction of the screen in order to place the screen at the focus of the lens, because a convex lens converges all the rays coming from a distant object on its focus.