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Homework Statement
A student stands at the edge of a cliff and throws a stone horizontally over the edge with a speed of 21.0 m/s. The cliff is h = 46.0 m above a flat horizontal beach
Initial v =21.0m/s
Delta Y= 46.0
Need to know, How long after being released does the stone strike the beach below the cliff? & With what speed and angle of impact does the stone land?
Homework Equations
I calculated the time = 3.06 which I got it right even though I didn't understand it. Square root of (46/4.9)=3.06s
The formula I used was "Delta Y=Vyo*T - (1/2)*g*(t square).
For some reason Initial velocity of Y was counted zero, eventhough it was given (21m/s).
The final velocity is 36.6. I don't understand How i get it right.
Vy = 21 + (-9.8)*5.88 => Vy = 36.6 m/s, Eventhought 5.88s was not the accurate answer for time (3.06s should be), but somehow 36.6 m/s was the right answer.
The Attempt at a Solution
I'm really having trouble finding the angle of impact below the horizontal.
First, I don't know what "below the horizontal means.
Second, I don't know how to calculate degree from inverse sine. I got to
.3149=sine of theta. The answer is close the 60degree, but I couldn't get it right.
Man, physics is tough. It's not just the math, but my textbook doesn't really explain much. Maybe I'm a bit slow, but the textbook doesn't show every step. It skip steps, jump around formulas and doesn't show all the work. Is there any website out there that shows detail steps? (for intro physics) :yuck: