# Constants in Projectiles

1. Jul 13, 2007

### avsj

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

For type 1, 2, or 3 projectiles, which of the following are constant?

Dx, Dy, Vx, Vy

2. Relevant equations

3. The attempt at a solution

I figure that the only one that is constant in all situations would be Vx because there is no acceleration in the x direction.

Dx would change depending on the height of launch, so would dy, and Vy, would depend on height as well because of gravity. But am I interpreting 'constant' correctly. Vx is the only horizontal straight line in a graph vs time but others are straight just not horizontal.

Basically, what does constant mean in physics in the context of this question?

2. Jul 13, 2007

### Kurdt

Staff Emeritus
What are type 1, 2 and 3 projectiles? What are the quantities you have listed? Presumably Vx and Vy are velocity in the x and y directions respectively. Are the D's distance?

3. Jul 13, 2007

### avsj

Type 1- horizontal launch off cliff
Type 2 - angled launch landing at same height as launch
Type 2 - angled launch landing at different height as launch

D is displacement
And V is velocity and x and y are the horizontal and vertical components respectively.