To calculate acceleration, you need to use the formula: acceleration = force / mass.
In this case, the force is 650 N and the mass is 100 kg, so the acceleration would be:
acceleration = 650 N / 100 kg
= 6.5 m/s^2
This means that if a force of 650 N is applied to an object with a mass of 100 kg, the acceleration of the object will be 6.5 m/s^2.