Q. A block of weight $9.8\, N$ is placed on a table. The table surface exerts an upward force of $10\, N$ on the block. Assume $g=9.8\, m / s ^{2}$. Select the correct statement(s).

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A

The block exerts a force of 10 N on the table

B

The block exerts a force of 19.8 N on the table

C

The block exerts a force of 9.8 N on the table

D

The block has an upward acceleration

Solution:

Newton's third law states that force applied by one object on other is exactly of same magnitude that applied by other on first. As net force on the block is in upward direction hence the block accelerates in upward direction.

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