# Spring and constant force

1. Oct 20, 2015

### Raios168

1. The problem statement, all variables and given/known data
A mass is attached to a spring which is mounted onto a wall. This mass is on a frictionless horizontal surface. You apply a CONSTANT force to the mass and it comes to a stop in 10 cm.

My question is, that since the mass comes to a stop in 10 cm then:
Force Applied = kx where x is 10/100 m

Is my reasoning correct? Thanks in advance

2. Oct 20, 2015

### Staff: Mentor

Hi Raios168. Please use the entire formatting template when you post a problem.

What happens to the kinetic energy that the mass gains while the spring force is less than the applied force?

3. Oct 20, 2015

### JBA

Is that the only question in the problem statement given to you; or, are there additional questions to be answered?

4. Oct 20, 2015

### Raios168

This is not the entire question I just wanted to know if my thinking was correct. The entire question with the variables is as follows:

A mass (1.20 kg) is attached to a spring (k = 790 N/m) which is mounted onto a wall. This mass is on a frictionless horizontal surface. You apply a CONSTANT force to the mass while the spring is in the unstretched position and the mass comes to a momentary stop in 10 cm.

5. Oct 20, 2015

### Raios168

The kinetic energy becomes elastic potential energy doesn't it?

6. Oct 20, 2015

### Mister T

It's impossible for us to tell that with only the information you've given us. We could guess, and if we guess wrong we do more damage than good.

Which is why you need to fill out the template.

7. Oct 20, 2015

### JBA

I think the key in the question is the "momentary stop". What provided the energy or (work) to get it to that point?

8. Oct 20, 2015

### Staff: Mentor

It does. And the KE built up while the spring's force is less than the applied force allows the mass to pass the point where the two forces are equal. That's why mass-spring systems oscillate.