A machine lifts a load of 12kN with an applied effort of 4kN. What distance will the load move if the effort moves a distance of 8m and the efficiency of the machine is 70%?

To determine how far the load moves given the applied effort and the efficiency of the machine, we can utilize the relationship of work input and work output along with the efficiency percentage.

First, we know that Efficiency is defined as the ratio of useful work output to the total work input. The formula is given by:

[ \text{Efficiency} = \frac{\text{Useful Work Output}}{\text{Total Work Input}} \times 100 ]

In this scenario:

• The effort is 4 kN, and it moves a distance of 8 m. Therefore, the work input is:

[ \text{Work Input} = \text{Effort} \times \text{Distance moved by Effort} = 4 \text{ kN} \times 8 \text{ m} = 32 \text{ kN·m} ]

Next, since the efficiency of the machine is 70%, we can calculate the useful work output:

[ \text{Useful Work Output} = \text{Efficiency} \times \text{Total Work Input} = 0.70 \times 32 \text{ kN·m} = 22.4 \text{ kN·m}