An engine weighing 350 pounds is raised and moved by a mobile hoist. How much work is done if it is lifted 3 feet and moved 12 feet with a constant force of 70 pounds?

To determine the total work done on the engine, it is crucial to consider both the vertical and horizontal movements separately since work is calculated as the product of force and distance.

First, when the engine is lifted vertically, the work done can be calculated using the formula:

[ \text{Work} = \text{Force} \times \text{Distance} ]

In this case, the force is equal to the weight of the engine, which is 350 pounds, and the distance lifted is 3 feet. Thus, the work done in lifting the engine is:

[ \text{Work}_{\text{lift}} = 350 , \text{pounds} \times 3 , \text{feet} = 1,050 , \text{foot-pounds} ]

Next, while the engine is being moved horizontally, the work done can be calculated again using the same formula. The constant force applied during the horizontal movement is 70 pounds, and the distance moved is 12 feet. Hence, the work done in moving the engine horizontally is:

[ \text{Work}_{\text{move}} = 70 , \text{pounds} \times 12 , \text