A particle of mass m describes a circle of radius r . centripetal acceleration of the part

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3-2.Motion in Plane

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A particle of mass $m$ describes a circle of radius $r$. The centripetal acceleration of the particle is $4/r^2$. What will be the momentum of the particle?

A$2\, m/r$

B$2m/ \sqrt r$

C$4m/ \sqrt r$

D$4 \,m/r$

Solution

$a_{c}=\frac{4}{r^{2}}$
$\frac{v^{2}}{r}=\frac{4}{r^{2}}$
$\mathrm{v}=\frac{2}{\sqrt{\mathrm{r}}}$
so $P=\mathrm{mv}$
$=\frac{2 m}{\sqrt{r}}$

Standard 11

Physics

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