A) 3.14 sec
B) 16.28 sec
C) 1.57 sec
D) none of these
Correct Answer: A
Solution :
Here: Time\[t=2\]sec, height\[h=8\text{ }m\] Initial velocity \[v=0\] Length of pendulum\[=1\text{ }m\] Relation for the height is given by, \[h=ut+\frac{1}{2}g{{t}^{2}}\] \[8=0\times 2+\frac{1}{2}g\times {{2}^{2}}=2g\] \[2g=8\]or \[g=4\text{ }m/{{s}^{2}}\] Hence, the time period T is given by, \[=2\pi \sqrt{\frac{l}{g}}=2\pi \sqrt{\frac{1}{4}}=\pi \] \[=3.14\text{ }sec\]You need to login to perform this action.
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