A) 12 J
B) 9J
C) 6J
D) 3J
Correct Answer: D
Solution :
Distance, \[s=\frac{{{t}^{2}}}{4}\] \[ds=\frac{t}{2}dt\] \[F=ma=\frac{m{{d}^{2}}s}{d{{t}^{2}}}\] \[=\frac{6{{d}^{2}}({{t}^{2}}/4)}{d{{t}^{2}}}=3N\] Now, \[W=\int_{0}^{2}{F}ds=\int_{0}^{2}{3}\frac{t}{2}dt\] \[=\frac{3}{2}\left[ \frac{{{t}^{2}}}{2} \right]_{0}^{2}=\frac{3}{4}[{{(2)}^{2}}-{{(0)}^{2}}]\] \[=3J\]You need to login to perform this action.
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