This is a difficult question to ask since I don\'t understand it myself and I am

Question

This is a difficult question to ask since I don't understand it myself and I am normally pretty good at my physics work. Must be old formulas that I don't remember and cant find but here it goes:

A projectile m=10kg is launched from ground level at an angle of 50 degrees above the horizontal with an initial speed of 55 m/s. Assume the ground under the projectile is perfectly flat throughout the projectile's flight.

If we ignore air resistance and assume the projectile stays relatively close to the surface of the Earth, the acceleration of the projectile in the horizontal (x) and (y) directions is constant:
asubx = 0 and asuby = g = 9.8 m/s² downwards

The rest of this really is not needed for anyone really good at physics but i'm gonna list it anyhow just to make sure no info. is missing:

vx (velocity in horizontal direction)
vy (velocity in vertical direction)
v (speed of the projectile)
y (height of the projectile)
K (kinetic energy)
Ug (gravitational potential energy)
ME (total mechanical energy)

vx, vy ,and y can be found directly from the kinetic equations for constant acceleration and v=v(vx2+vy2). See Lab #3 for details.
Note: when y<0, the object has already hit the ground.

Kinetic energy is an object's energy due to it's motion. As an equation,

K=1/2mv2

Gravitational potential energy is the stored energy of an object due to it's relative position in a gravitational field. If we define the ground to have
zero potential energy (our zero reference level), the gravitational potential energy of an object a distance 'y' above the ground can be written as

Ug=mgy

The total mechanical energy of an object is the sum of the kinetic plus the potential energies (ME=K+Ug). If the forces acting on an object are
conservative the total mechanical energy is time invariant (constant).


What I'm looking for are the formulas to find v(sub)x, v(sub)y, v, y, K, Ug, ME.
The exact meaning for all of those are listed above as well.

I know some of the formulas allready but figured it would be easier to ask for all of them to make sure so I put them together correctly because my graph is coming out all over the place so I'm surely messing 1 or 2 of the formulas up.

Further info: I'm actually filling these formulas into an Excel sheet to make a graph with the only info given in the actual excel sheet being t = 0 to t = 9 in .5 second intervals. So there is no hidden info on the excel sheet itself.

Explanation / Answer

Ok so your question was very convoluted but I'm assuming you're looking for the various equations from newtons law of motion to model the movement of the ball. You can derive everything from the basic equation: Height(final) = height(initial) + velocity(initial) * time + 0.5* acceleration * time^2 So since were ignoring air resistance your horizontal velocity will be Vx = v(initial) * cosine(angle) Vy = V(initial) + acceleration * time In this case you must only consider the vertical component of velocity so Vy(initial) = V(initial)* sine(angle) Total projectile speed will be the vector sum of the horizontal and vertical components or V(projectile over path) = SQRT(Vx^2 + Vy^2) Final position Sf = Si + 0.5(Vf+Vi)* time Your formulas for kinetic, potential and total mechanical energy are correct so that should be all. If you need me o solve anything, let me know. Note: be sure to note the direction of acceleration in the y direction(ie gravity acting agains motion of ball so tha component becomes negative)

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