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a ball is approaching a convex mirror of focal length 30 cm with speed 20 m/s. calculate the speed of its image when the ball was at 5 m from the mirror? (a)

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Final answer:

The speed of the image when the ball is 5 m from the mirror is approximately 0.3 m/s.

Step-by-step explanation:

To calculate the speed of the image, we can use the mirror equation:

1/object distance + 1/image distance = 1/focal length

Given that the object distance (u) is 5 m and the focal length (f) is 30 cm (0.3 m), we can plug these values into the equation to find the image distance (v).

Simplifying the equation, we have:

1/5 + 1/v = 1/0.3

Multiplying through by (5v), we get:

v + 5 = 16.6667v

Subtracting v from both sides, we have:

5 = 15.6667v

Dividing both sides by 15.6667, we get:

v ≈ 0.3 m/s

Therefore, the speed of the image when the ball is 5 m from the mirror is approximately 0.3 m/s.

User Anton Ashanin
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