A) 0.4 m/s
B) 4 m/s
C) 0.2 m/s
D) 2 m/s
Correct Answer: D
Solution :
[d] Given, \[\theta =45{}^\circ ,\]\[r=0.4\,m,\]\[g=10m/{{s}^{2}}\] \[T\sin \theta =\frac{m{{v}^{2}}}{r}\] ?(i) \[T\cos \theta =mg\] ?(ii) From equation (i) & (ii) we have, \[\tan \theta =\frac{{{v}^{2}}}{rg}\] \[{{v}^{2}}=rg\] \[\because \] \[\theta =45{}^\circ \] Hence, speed of the pendulum in its circular path, \[v=\sqrt{rg}=\sqrt{0.4\times 10}=2\,\,m/s\]You need to login to perform this action.
You will be redirected in
3 sec