Apositively charged metal ball a is placed near metal ball b. show that if the charge on b is positive but of small magnitude, the balls will be attracted to each other.

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The duration of a photographic flash is related to an rc time constantly

The best answer is (a) which is universal law is in effect at all times. it is constantly at play in everything we do and governs our lives. it is also important to note that universal law applies to not only everything on earth, but everything in the universe as well, which is another reason why it is in effect at all times.