A planet moving in an elliptical orbit is closest to the Sun at distance r₁ and farthest away at distance r₂. If its respective linear speeds are v₁ and v₂, the ratio v₁/v₂ is:
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A planet moving in an elliptical orbit is closest to the Sun at distance r₁ and farthest away at distance r₂. If its respective linear speeds are v₁ and v₂, the ratio v₁/v₂ is:

G1 Physics · Accepted Answer

Step 1: At nearest and farthest points velocity is perpendicular to the radius vector. Step 2: Gravitational torque about the Sun is zero; angular momentum is conserved: mr₁v₁=mr₂v₂, giving v₁/v₂=r₂/r₁. Final answer: A — r₂/r₁.