1. Dec 19, 2009

### pallidin

I can't seem to wrap my head around this. Perhaps you can help:

Let's say I've managed to accelerate a mass to 1/2c.
Now, I wish to get that mass going faster, BUT, the newly applied force is not enough to do this.

What then happens to the "insufficient" applied energy? Is it absorbed, reflected, dissipated, etc...?

Thanks

Last edited: Dec 19, 2009
2. Dec 19, 2009

### Staff: Mentor

What do you mean? If you apply a force the object will accelerate and the energy will be equal to the force times the distance.

3. Dec 19, 2009

### pallidin

Dale,

If the force is unable to further accelerate the mass(by virtue of that force being weaker than required to overcome inertia) what happens to the applied force?

It is my understanding(perhaps wrong) that an applied force MUST be sufficient enough to overcome the inertia of the mass or the mass will NOT accelerate.

4. Dec 19, 2009

### Staff: Mentor

This is a misunderstanding. Any net force, no matter how small, will result in an acceleration. If the force is very small relative to the mass then the acceleration will be correspondingly small, but it will still be there.

You may be thinking of static friction, where you have to apply a force greater than the static friction force in order for there to be a net force so that the object can start moving.

5. Dec 19, 2009

### pallidin

OK. Thank you so much.