A construction crane lifts a bucket of sand originally weighing 140lbs at a constant rateSand is lost from the bucket at a constant rate of 0.5lb/ftHow much work is done in lifting the sand 70ft? (Neglect the weight of the bucket)Please help I am really confused and need an explanation
Not confirmed but i hope it can serve the purpose of both.
It'll workThermoses are just as good at keeping heat in as they are at keeping heat out.
As long as the rate of loss of sand is constant, you can use the average weight of sand in the bucket as the weight0.5 lbper foot over 70 feet results in a loss of 35 pounds of sandThat means the average amount of sand in the bucket is: 140 - (35/2) 122.5 lbWork done: W fd 122.5(70) 8575 lb.ft.
