If A has diameter of 6cm ams B has diameter of 12cm what ia the no of ratation A makes by the time B complete one rotation?

### Asked by VAshwika23 | 18th Dec, 2019, 06:46: AM

Expert Answer:

### A moves over circular path having diameter 6 cm
Thus, r = 3 cm
Thus, distance travelled by A is = 2∏r = 2 x 3.14 x 3 = 18.84 cm
B moves along circle of diameter of 12 cm
Thus, r1 = 6 cm
Thus, distance tavelled by B = 2∏r1 = 2 x 3.14 x 6 = 37.68 cm
From this it is clear that the time taken by A to complete one rotation will less than time taken by B.
Also, by the time B completes one rotation the distance covered by A will be more than B as the circle along which it is moving is less than that travelled by B.
Let's consider that B completes one rotation in 't' seconds then the number rotations completed by A in 't' seconds will be = 37.68 cm/18.84 cm = 2
Thus, number of rotations completed by A along its path by the time B complete its 1 rotation are 2.

### Answered by Shiwani Sawant | 18th Dec, 2019, 01:06: PM

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