What are the basics of energy transfer and projectile motion?

im doing a science assignment and in the discussion section it asks me about the basics of energy transfer and projectile motion, since i have had so many assignments, my brain is dead and i cant remember those basics. can anyone help?What are the basics of energy transfer and projectile motion?In three words, the basics are the "conservation of energy." No more, no less.



This means the total energy the projectile starts with at the muzzle (launch point) is the total energy it will have upon impact. And in fact, the total energy TE is fixed at any waypoint in the trajectory. What changes is the content of that TE.



If drag is discounted, we can write in general terms:



At the muzzle...

TE = KE + pe; the total energy at the muzzle is kinetic energy KE plus the potential energy at the height h of the muzzle. KE = 1/2 mV^2 = 1/2 m (Vx^2 + Vy^2) where V is the muzzle velocity and Vx = V cos(theta) and Vy = V sin(theta). Theta is the muzzle elevation angle.



At max height H above the ground...

TE = KEx + PE = KEx + pe + mgy; KEx is the kinetic energy from Vx the X direction velocity, pe is the muzzle potential energy, and mgy is the additional potential energy as the project climbs y height above the muzzle to H = h + y above the ground or impact level so that PE = mgH



Upon impact...

TE = KEx + KEy = KEx + 1/2 m (2gH); where m is the mass of the projectile and 2gH = Vy^2.



As you can see, from the conservation of energy, we have three equivalent equations for total energy TE. This gives us a lot of opportunity to solve for various variables.



Note, if drag is considered, Vx and Vy are decelerated by the drag forces. So none of the above is valid for cases where drag is significant. And, unfortunately, as drag depends on velocity and velocity depends on drag, we have a looping situation that can only be handled by iteration, which means using computers unless you have a lot of time to waste doing them manually.What are the basics of energy transfer and projectile motion?If that's what you found to be energy transfer; then it has nothing to do with projectile trajectories. Energy conversion, yes, but not energy transfer. There is no transfer from one object to another in projectile motion because there is only the one object... the projectile.

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What are the basics of energy transfer and projectile motion?Once a projectile is launched, until it hits the ground, The sum of it kinetic energy + potential energy must be constant throughout the motion. There are two ways to represent this mathematically;



1) Total energy = constant "E"



E = (1/2)mv^2 + mgy



2) Total Energy at one point = Total energy at any other point



(1/2)mv1^2 + mgy1 = (1/2)mv2^2 + mgy2



The height ":y" may be measured from any reference level you choose. If its above that level "y" is positive. If its below that level "y" is negative.



Notice, the SUM of KE and PE is constant, not each one. If the projectile rises it looses KE and gains PE. If it drops it looses PE and gains KE.