CBSE-XI-Physics
12: Simple Harmonic Motion
- #6Which of the following quantities are always negative in a simple harmonic motion?
(a)
F→. a→.
(b)
v→. r→.
(c)
a→. r→.
(d)
F→. r→.Ans : `` \left(c\right)\stackrel{\rightharpoonup }{a}.\stackrel{\rightharpoonup }{r}``
`` \left(d\right)\stackrel{\rightharpoonup }{F}.\stackrel{\rightharpoonup }{r}``
In S.H.M.,
F = -kx
Therefore, `` \stackrel{\rightharpoonup }{F.}\stackrel{\rightharpoonup }{r}`` will always be negative. As acceleration has the same direction as the force, `` \stackrel{\rightharpoonup }{a}.\stackrel{\rightharpoonup }{r}`` will also be negative, always.
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