The diagram in the figure below represents a wheel and axle used as a machine, whose efficiency is 80% to raise 400N of building materials....

The diagram in the figure below represents a wheel and axle used as a machine, whose efficiency is 80% to raise 400N of building materials. The wheel and axle have diameters of 75cm and 15cm respectively.



(i) Mark on the diagram the correct position and direction of the load to be lifted.

(ii) Name the principle on which this machine works.

(iii) Calculate the effort needed to raise the load.

(iv) The machine is operated manually and raises the load to a height of 5m in 20 seconds. Calculate the power developed by the operator

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(i)


(ii) The principle of moments

(iii)


(iv)

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maurice.mutuku answered the question on August 22, 2019 at 08:32

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