A real object is 30 cm from a concave mirror. It moves at 10 cm/s making 37° with the axis toward the mirror. If |f|=20 cm, the magnitude of image velocity is closest to:
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A real object is 30 cm from a concave mirror. It moves at 10 cm/s making 37° with the axis toward the mirror. If |f|=20 cm, the magnitude of image velocity is closest to:

G1 Physics · Accepted Answer

At u=30, |m|=2. Object axial and transverse speeds are 8 and 6 cm/s. Image components are 32 and 12 cm/s. Resultant=√(1024+144)=√1168≈34.2 cm/s.