Question:
In an experiment, a small steel ball falls through a liquid at a constant speed of $10 \mathrm{~cm} / \mathrm{s}$. If the steel ball is pulled upward with a force equal to twice its effective weight, how fast will it move upward?
$5 \mathrm{~cm} / \mathrm{s}$
Zero
$10 \mathrm{~cm} / \mathrm{s}$
$20 \mathrm{~cm} / \mathrm{s}$
Question of from chapter.
JEE Main Previous Year Online April 25, 2013
Correct Option: 3
Solution:
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