Question

how much of work is done to build a column 4.8768m high with 4 marble blocks each of height 1.2192m and mass 90.72kg?​

Answer 1

Answer:

For first block on the table the work is zero because it is already on the table

For second we lift it above the first block so we lift it one thickness h. So the work done on the second block is W2=mgh

For the third block we lift it above the previous two blocks so the work done is W3=mg(2h)=2mgh

For the last block we lift it above the previous three so the work done is W4=mg(3h)=3mgh

So the total work done is

Wtotal=W1+W2+W3+W4=0+mgh+2mgh+3mgh=(1+2+3)mgh=6mgh

Explanation:

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