# Which direction will this object move in at the end of this process?

1. Consider an object with no net force acting on it moving with a constant velocity $$v$$. It has a momentum $$mv$$.

2. Now let a force $$F_1$$ act on the object. Let the direction of this force be opposite (to the direction of the object's constant velocity)

3. The object now undergoes a change in its momentum over time, accelerating in the direction of the force $$F_1$$

4. Let another force $$F_2$$ be introduced that is equal in magnitude to $$F_1$$ but opposite in direction.

Question: What happens to the object now?

Since under the influenced of balanced forces the object can either be at rest or have a constant velocity. If it does have a constant velocity what will be its direction?

And what is the work done by the two forces? • As $F_1$ is applied the object's velocity component in its original direction of motion will decrease. That should be fairly obvious. Suggest you start by writing an equation for this velocity component, showing how it depends on time $t$ from when $F_1$ started to be applied. Dec 7, 2018 at 18:49

The object will stop to accelerate since the two forces cancel each other. The final velocity v will be $$v=v_0+a*t_0$$ where $$v_0$$ is the initial velocity, a the acceleration provided by $$F_1$$ and $$t_0$$ the time until $$F_2$$ is applied. Note that $$v_0$$ and $$a$$ most likely have different direction.