An object in air approaches a stationary convex spherical glass surface of radius +20 cm at 2 cm/s. At the instant u=-30 cm, μ=3/2. What is the instantaneous image velocity?
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An object in air approaches a stationary convex spherical glass surface of radius +20 cm at 2 cm/s. At the instant u=-30 cm, μ=3/2. What is the instantaneous image velocity?

G1 Physics · Accepted Answer

First v=-180.00 cm. Differentiation gives dv/dt=(μ₁/μ₂)(v/u)²du/dt=48.000 cm/s.