Bob needs to accelerate a 4 kg box at 2 m/s2. How much force does he need to use?

8 N

Explanation:

From Newtons second law of motion, we have;

F = ma

where: F is the force applied, m is the mass of the object, and a is its acceleration.

From the given question: mass of box  = 4 kg and acceleration of the box  = 2 m/, then;

F = 4 x 2

  = 8

F = 8 N

The amount of force to be used is 8 N.  

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