Physics-
General
Easy
Question
A point object 'O' approaches a biconvex lens of focal length 40 cm along its optic axis with a speed of 
while the later recedes away from the former with a speed of 4 cm/s. Find the speed and direction of motion of the image when the abject is at a distance of 60 cm from the lens.
- (10 an/s, leftwards)
- 10 cm/s, right wards
- 28 cm/s rightwards
- 28 cm/s leftwards
The correct answer is: 28 cm/s rightwards
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