Carlos pushes a 3 kg box with a force of 9 newtons. The force of friction on the box is 3 newtons in the opposite direction. What is the acceleration of the box?

friction = 3 N

pushing force = 9 N

as both are opposite in direction so their net force will be = 9-3 = 6N

as we know that

F = ma

re arranging the equation

a = F/m

by putting values

a = 6/3 N/kg

a = 2 m/sec²

The 'net' force acting on the box is (9 - 3) = 6 newtons

in the direction that Carlos is pushing.

Force = (mass) x (acceleration)

6 = (3) x (acceleration)

Divide each side by 3:

2 m/s² = acceleration