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Physics · MOTION IN A PLANE
हिन्दीIn the motorboat problem, if \( \phi \) is the angle made by the resultant velocity \( \mathbf{R} \) (\( 21.8\text{ km/h} \)) with the velocity vector of the motorboat (\( 25\text{ km/h} \) North), then \( \sin\phi \) is equal to:
Correct answer · Option 2
\( \sin\phi = \frac{10\sqrt{3}}{2 \times 21.8} \approx 0.397 \)
Explanation
By the Law of sines: \( \frac{R}{\sin 120^\circ} = \frac{v_c}{\sin\phi} \implies \sin\phi = \frac{v_c \sin 120^\circ}{R} = \frac{10 \times (\sqrt{3}/2)}{21.8} = \frac{10\sqrt{3}}{2 \times 21.8} \approx 0.397 \).
