A projectile is to be fired from the origin so that it passes through the point P(20 m, 15 m). Neglect air resistance and take g = 10 m/s². The minimum possible speed of projection is:
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Question

A projectile is to be fired from the origin so that it passes through the point P(20 m, 15 m). Neglect air resistance and take g = 10 m/s². The minimum possible speed of projection is:

G1 Physics · Accepted Answer

For a projectile to reach a point (x, y), the minimum launch speed satisfies uₘᵢₙ² = g[y + √(x² + y²)]. Here √(20² + 15²) = 25 m. Thus uₘᵢₙ² = 10(15 + 25) = 400, so uₘᵢₙ = 20 m/s. Therefore option C is correct.