# Central force

1. Jun 8, 2010

### anirudh dutta

1. The problem statement, all variables and given/known data
a body of mass 1kg moves under the influence of a central force with potential energy question V(r)= -exp(-3r/2)/5r2
.it is found to move under a circular orbit of radius 2 m

2. Relevant equations
find the total energy and the angular momentum

3. The attempt at a solution

2. Jun 8, 2010

### phyzguy

You need to at least attempt to solve the problem if you expect help.

3. Jun 8, 2010

### anirudh dutta

see, since i have the potential energy fn, i can calculate the force by calculating the negative of grad of V.
This force will be balanced by the centripital corce i.e mv^2 /r. from here i can cal the velocity, v.
thus the angular mom is simply mvr and total energy is P.E+K.E

4. Jun 8, 2010

### phyzguy

Sounds good. So what is your question?

5. Jun 9, 2010

### anirudh dutta

firstly the mathematical calculation is very tedious. So is there sm another meathod

6. Jun 9, 2010

### phyzguy

I don't know of a better way. It doesn't look that bad. If you have access to software like Mathematica, it will be a snap, but even without that it should be less than one page.

7. Jun 10, 2010

### cartonn30gel

Your method seems correct and it's not tedious at all. You should be able to do it with pencil and paper just fine.