A) \[\frac{{{m}_{1}}gR}{{{B}^{2}}{{l}^{2}}}\]upward
B) \[\frac{{{m}_{1}}gR}{{{B}^{2}}{{l}^{2}}}\] downward
C) \[\frac{{{m}_{1}}gR}{2{{B}^{2}}{{l}^{2}}}\]downward
D) \[\frac{{{m}_{1}}gR}{{{B}^{2}}l}\] downward
Correct Answer: B
Solution :
[b] For terminal velocity Net force =0 So, \[{{m}_{1}}g={{F}_{m}},{{m}_{1}}g=Bi\ell =B\left( \frac{B\ell v}{R} \right)\ell ,v=\frac{{{m}_{1}}gR}{{{B}^{2}}{{\ell }^{2}}}\]You need to login to perform this action.
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