# Homework Help: Does height affect the constant of proportionality?

1. Aug 26, 2007

### mwahx3

1. The problem statement, all variables and given/known data

Does height affect the constant of proportionality?

'k'

2. Relevant equations

no relevant equations

3. The attempt at a solution

I don't think it does but I'm not sure why though.

2. Aug 26, 2007

### learningphysics

I don't understand... is k a spring constant?

3. Aug 26, 2007

### mwahx3

hookes law.

4. Aug 26, 2007

### learningphysics

k is constant within a certain range of stretching... beyond that the spring is damaged and doesn't work as Hooke's law predicts...

height doesn't affect it.

5. Aug 26, 2007

### mwahx3

hmmm. but in the example they use falling objects...not springs. thats what I'm stuck on.

6. Aug 26, 2007

### learningphysics

But Hooke's law is for springs. For falling objects, you probably don't need Hooke's law... unless I'm misunderstanding something.

7. Aug 26, 2007

### mwahx3

ahhh. sorry what i said about hookes law. for falling objects, it stays constant since it is the acceleration. is this correct?

8. Aug 26, 2007

### learningphysics

Well, acceleration is approximated to g close to the earth... technically it does change with height... but for most gravity/falling object problems (where we aren't dealing with astronomical distances), it is taken as constant = g = 9.8m/s^2

9. Aug 26, 2007

### mwahx3

oh wait! sorry i misunderstood the problem! k is the constant of proportionality for the DRAG. so air resistance. but it still doesn't change does it?

10. Aug 26, 2007

### mwahx3

oh wait! sorry i misunderstood the problem! k is the constant of proportionality for the DRAG. so air resistance. but it still doesn't change does it?

11. Aug 26, 2007

### learningphysics

I don't think so... if the question gives it as a constant, then don't worry about it changing...

12. Aug 26, 2007

### mwahx3

okay. thank you.