Question

600 joules of work is used to lift a box from the ground to a height of six meters. how much work would have been done if a lever would have been used with an effort arm of 12 meters and a load arm of 6 meters? (1 point) 100 j 50 j 600 j 72 j

Explanation:

Step1: Recall the principle of work

Work done \(W = F\times d\). Also, for a lever, the work input \(W_{in}\) equals the work output \(W_{out}\) (assuming no energy loss due to friction etc., which is a common assumption in basic physics problems about levers).

Step2: Analyze the given situation

When we lift the box directly, the work done is \(W = 600\ J\). When using a lever, the work input (effort - related work) and work output (load - related work) follow the law of conservation of energy for simple machines (in the ideal case). The work done in lifting the box (work output) is still determined by the force applied on the load (weight of the box \(F_{load}\)) and the height \(h\) it is lifted (\(W_{out}=F_{load}\times h\)). When using a lever, \(W_{in}=W_{out}\). The formula for the lever is \(F_{effort}\times L_{effort}=F_{load}\times L_{load}\), but the work \(W = F\times d\). The vertical displacement of the load (height \(h = 6\ m\)) and the nature of the task (lifting the box) remain the same. The work done in lifting an object is a measure of the energy transferred to the object. The lever changes the force - distance relationship (\(F_{effort}\times d_{effort}=F_{load}\times d_{load}\), where \(d_{effort}\) and \(d_{load}\) are the distances moved by the effort and the load respectively), but the total work (energy transferred to lift the box to a height of \(6\ m\)) does not change in an ideal situation.

Answer:

600 J