A number of identical cubical blocks of edge $'a'$ and mass $m$ are lying on a horizontal table. The work done on the blocks in arranging them in a column of height $(n + 1)a$ on the table is
A number of identical cubical blocks of edge $'a'$ and mass $m$ are lying on a horizontal table. The work done on the blocks in arranging them in a column of height $(n + 1)a$ on the table is
- A
$\frac{1}{2}ma\,g{n^2}$
- B
$\frac{1}{2}ma\,g\left( {{n^2} + n} \right)$
- C
$\frac{1}{2}\left( {{n^2} - 2} \right)mag$
- D
$\frac{1}{2}{\left( {n + 1} \right)^2}mag$
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