Final answer:
The object will accelerate at a rate of 4 m/s² when pushed with a 400N force.
Step-by-step explanation:
To determine the acceleration of the object, we can use Newton's second law of motion which states that the acceleration is equal to the net force acting on an object divided by its mass. In this case, the net force is 400N and the mass of the object is 100kg. Therefore, the acceleration is:
acceleration = net force / mass
acceleration = 400N / 100kg = 4 m/s²
So, the object will accelerate at a rate of 4 m/s² when pushed with a 400N force.