Projectile Motion from a cliff with no information.

AI Thread Summary
The discussion revolves around calculating the direction of the velocity vector of a cannonball fired horizontally from a cliff, where the range equals the height of the cliff. The initial approach involved equating horizontal and vertical displacements, but confusion arose regarding the angle of impact. The solution indicates that the angle of the velocity vector upon striking the ground is 63.4 degrees below the horizontal. The calculations involve using the equations for horizontal and vertical motion, with the initial vertical velocity being zero. Ultimately, the participant resolved their confusion and found the correct solution.
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Homework Statement


The range of a cannonball fired horizontally from a cliff is equal to the height of the cliff. What is the direction of the velocity vector of the projectile as it strikes the ground? (ignore air resistance)


Homework Equations



I attempted setting delta y = delta x, but had not luck.

The Attempt at a Solution



The apparent solution is 63.4 degrees below the horizon.
 
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delta x= v[initial]*t and delta y=0.5*g*t*t as velocity is zero along y-axis initially.
What do you get when you equate the two?
 
I get inital velocity = .5*g*t. I found that solution earlier but I do not understand how they get an angle from that information?
 
This velocity of yours is along which axis?
 
I honestly am very confused at this point.
 
I figured it out thanks for the help.
 
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