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A velocity $$\frac{1}{4}$$ m/s is resolved into two components along $$OA$$ and $$OB$$ making angles $$30^\circ$$ and $$45^\circ$$ respectively with the given velocity. Then the component along $$OB$$ is
Let the given velocity be
$$R=\frac14\text{ m/s}$$
Let the components along $$OA$$ and $$OB$$ be $$P$$ and $$Q$$ respectively.
The resultant $$R$$ lies between the directions $$OA$$ and $$OB$$ and makes angles
$$30^\circ$$
and
$$45^\circ$$
with them.
Hence the angle between the component directions is
$$30^\circ+45^\circ=75^\circ$$
Using the triangle of forces (or velocities) and applying Lami's theorem,
$$\frac{P}{\sin45^\circ}=\frac{Q}{\sin30^\circ}=\frac{R}{\sin75^\circ}$$
Therefore,
$$Q=\frac{R\sin30^\circ}{\sin75^\circ}$$
Substituting
$$R=\frac14$$
gives
$$Q=\frac14\cdot\frac{\frac12}{\sin75^\circ}$$
Using
$$\sin75^\circ=\frac{\sqrt6+\sqrt2}{4}$$
we get
$$Q=\frac{1}{2(\sqrt6+\sqrt2)}$$
Rationalising,
$$Q=\frac{\sqrt6-\sqrt2}{8}$$
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