Two particles move with equal speed 20 cm s⁻¹ along two straight lines intersecting at 60°. At an instant they are 3 m and 4 m from the intersection O and both move toward O. The subsequent shortest distance between them is:
Options

Question

Two particles move with equal speed 20 cm s⁻¹ along two straight lines intersecting at 60°. At an instant they are 3 m and 4 m from the intersection O and both move toward O. The subsequent shortest distance between them is:

Options

G1 Physics · Accepted Answer

Use relative motion: r(t)=r₀+vᵣ t. The minimum separation is the perpendicular distance from the initial relative-position vector to the relative-velocity line. Substituting the given geometry and equal speeds gives 50√3 cm. Option D.