Question

A block of mass $2kg$ is sliding with a constant velocity of $8m/s$ on a frictionless horizontal surface. The force exerted on the horizontal surface is nearly :

• A. 20 N
• B. 10 N
• C. 40 N
• D. 16 N

Answer 1

The correct option is A 20 N

The $FBD$ will be as

For equilibrium in vertical direction

$N-mg=0$

$N=mg=\left(2\right)10=20N$

The normal contact force applied by the surface is $20N$, thus by Newton's third law of motion, $20N$ force will be exerted by the block on the surface.

Option $A$ is correct.