How to calculate projectile off cliff when angle is below th

Abcdefghijk

Homework Statement


Cliff is 50 m tall
Stone thrown downwards with velocity of 12 m/s and 22 degrees below horizontal
What is the time it will take to hit the ground?


Homework Equations


V=d/t
D= Vi t + 1/2at^2

The Attempt at a Solution


Vx1= cos (22)(12)
= +11.12620625
Vy1= sin (22) (12)
= -4.495279121

I solved the triangle (hyp=12) but from here I am not sure what to do. Here is what I attempted from here:

Vertical
(Vi= 0 m/s, a (g)= -9.81 m/s^2, d= 50 m)
d= Vi t + 1/2at^2
t (re-arranged) = square root of d/(1/2a)
t= 10. 1936792 s

Horizontal
(V= 12 m/s, t= 10.1936792 s)
v= d/t
d= vt
d= (12)(10...)
d= 122.324159 m

The correct answer is 2.77 seconds, but I am unable to get this answer and comprehend how to achieve this answer. I would greatly appreciate a walkthrough/explanation of this question and if the angle was above the horizontal as well.

Thanks

 
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Abcdefghijk said:
d= Vi t + 1/2at^2
t (re-arranged) = square root of d/(1/2a)
t= 10. 1936792 s
What happened to vi t? Isn't there a downward initial velocity component?
 
For the vertical component, the initial velocity should be 0 m/s since the movement is horizontal. Therefore I think that you can eliminate Vi t as it will yield 0.
 
Abcdefghijk said:
Stone thrown downwards with velocity of 12 m/s and 22 degrees below horizontal
This means what is says. The stone is not shot horizontally. In fact you calculated its vertical component here
Abcdefghijk said:
Vy1= sin (22) (12)
= -4.495279121
What do you think Vy1 is?
 
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