# What kind of math do I include in THIS?

1. Oct 17, 2008

### Ashleyz

Here is the problem. The only help I need with this is
to determine the SPECIFIC type of defferential equations to use.
(if any at all)
i.e, 1st ODE's, ect.

A rocket starts from rest on a ramp.

Its propellant is consumed at a constant rate for a certain time.

The propellent burns out after a certain time.

Now the rocket is a projectile. It will land due to gravity at a certain D (distance) from ramp.

2. Oct 17, 2008

### atyy

Last edited by a moderator: Apr 23, 2017
3. Oct 17, 2008

### Ashleyz

This site is great, but I have never studied Diff. Eq. and need
to know what section I need to look at in order to solve the problem.

I need to understand, not copy and past.

4. Oct 18, 2008

### atyy

Why not post your problem in more detail, and show us how far you've gotten and where you're stuck?

5. Oct 18, 2008

### Ashleyz

This is a problem I am putting together(it is not homework) and need help only on
deciding if I need to include a differential equation.
If I do, then what kind? I have never taken a class on D.E's, so need help narrowing down what type.

The problem is conservation of momentum, and I am only working with variables at first.

The first part is the hard part, as the M(mass) of the P(propellent) is changing with time.
-this is the part that I believe I may need to include some ODE's.

I have made the 2nd part to this problem easy, bc the fuel runs out, and now we are dealing with an easy projectile.