Question

A bar of mass 2 kg lying on a rough horizontal surface begins to move with an acceleration of 3 m/s2 if a horizontal force of 11 N is applied to it. Find the smallest value of the horizontal force (in N) that can move the bar.​

Answer 1

• 6N

Given :

• Mass = 2kg
• Acceleration = 3m/s²

To find :

• Minimum value of the horizontal force

Solution :

We know that,

• The Minimum horizontal force = frictional force

Also,

• Friction force = Mass x Acceleration

Thus,

• The minimum horizontal force = 2kg x 3m/s²
• The minimum horizontal force = 6N

Thus, 6N would be the smallest value of the horizontal force that can move the bar.