Physics
(a) The diagram below shows a heavy roller with its axle at O. Draw on the diagram the direction and the point of application of the least force to turn it anticlockwise.
(b) How can you change the direction of turning of roller in part(a) above.
Answer
(a) In order to rotate the heavy roller in anticlockwise direction, we need to apply force F as shown in the diagram below:
(b) The direction of turning of roller can be changed from anticlockwise to clockwise direction in two ways:
(1) The direction of application of force can be changed, keeping the point of application of force the same as shown in the diagram below:
(2) The point of application of force can be changed, keeping the direction of application of force the same as shown in the diagram below:
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