Answer :
Using a lever to move a rock reduces the force a person must exert . It also reduces the work (effort ) the person must do.
Using a lever decreases the input force required to lift up the load, for example if a force of 900N is required to lift the load without a lever . Using the lever the input force decreases to 500N and as we all know by the formulae of work done :
Work done ∝ force applied
By this equation we can conclude that if the force to be applied on the load reduces by the use of a lever therefore the work to be done on the load will also reduce .
You can get a additional information about the lever system below :
https://brainly.com/question/3522307
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