CBSE-XI-Physics
12: Simple Harmonic Motion
- #8Which of the following quantities are always zero in a simple harmonic motion?
(a)
F→× a→.
(b)
v→× r→.
(c)
a→× r→.
(d)
F→× r→.Ans : `` \left(a\right)\stackrel{\rightharpoonup }{F}x\stackrel{\rightharpoonup }{a}``
`` \left(b\right)\stackrel{\rightharpoonup }{v}x\stackrel{\rightharpoonup }{\stackrel{\rightharpoonup }{r}}``
`` \left(c\right)\stackrel{\rightharpoonup }{a}x\stackrel{\rightharpoonup }{r}``
`` \left(d\right)\stackrel{\rightharpoonup }{F}x\stackrel{\rightharpoonup }{r}``
As `` \stackrel{\rightharpoonup }{F},\stackrel{\rightharpoonup }{a},\stackrel{\rightharpoonup }{r}and\stackrel{\rightharpoonup }{v}`` are either parallel or anti-parallel to each other, their cross products will always be zero.
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