Figure below shows a wheel and axle of radius R and r respectively.

Figure below shows a wheel and axle of radius R and r respectively.

(a) Show that the velocity ratio of the system is given by
(b) Given that r = 5cm, R = 20cm and an effort of 1200N is used to lift a load of 3000N. Determine:
i. The work done by effort to raise the load through a distance of 2m.
ii. The efficiency of the system.
iii. State two ways in which the efficiency in (ii) above can be increased.

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III. - Oiling / greasing the movable parts to reduce friction.
- Use lighter materials for movable parts.

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sharon kalunda answered the question on September 11, 2019 at 10:09

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