How can we say that magnetic effect can pass through screen?
This is well explained in the study material with the help of animation. Please refer the following link: http://cbse.meritnation.com/study-online/study-material/@OnKu8Q0mCI@IUOZY0oLwA!!/iQTVQ0PEKGqnITh4PPlXbg!!#3573