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Curry
 one year ago
Simple question. But trick involved. A ball is thrown horizontally from the top of a 10 meter high builiding. It strikes the ground at an angle of 30 degree. with what speed was it thrown?
Curry
 one year ago
Simple question. But trick involved. A ball is thrown horizontally from the top of a 10 meter high builiding. It strikes the ground at an angle of 30 degree. with what speed was it thrown?

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ganeshie8
 one year ago
Best ResponseYou've already chosen the best response.0was the angle with respect to ground ?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0thrown horizontally means angle was 90 degree dw:1433846133143:dw assuming no drag force , so the horizontal velocity is constant call it V0 and the vertical velocity is Vy =zero so the final vertical velocity is \[V _{T}^{2}V_{y}^{2} = 2 g h\] thus you have vy dw:1433846575866:dw so \[\tan 30 = \frac{ V _{0} }{ V _{y} }\rightarrow V _{0}= V _{y}* \tan30\] just plug in numbers

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0uh..oh I mixed Vt with Vy. hope you get the main point

Curry
 one year ago
Best ResponseYou've already chosen the best response.0hey, using the equation you gave me, the answer comes out to 8.1. But the actual answer is 24.

Curry
 one year ago
Best ResponseYou've already chosen the best response.0What i did was take the time it takes get to the bottom. Then i found out the horizontal distance using trig. Then i divided distance by time. Why is that wrong?

Curry
 one year ago
Best ResponseYou've already chosen the best response.0@nincompoop @IrishBoy123

radar
 one year ago
Best ResponseYou've already chosen the best response.0@curry, what time did you get for the ball to fall that vertical distance of 10 meters? I got 1.43 seconds.

radar
 one year ago
Best ResponseYou've already chosen the best response.0dw:1433885146576:dw @Catch.me

radar
 one year ago
Best ResponseYou've already chosen the best response.0Uh Oh gotta go now, but will return to see how this turned out lol

Curry
 one year ago
Best ResponseYou've already chosen the best response.0Yes, i got 1.43 seconds for time also. And then for the horizontal distance i got 10rad3. So i divided this value by 1.43 to get the horizontal speed. But that's not giving me the right answer.

Curry
 one year ago
Best ResponseYou've already chosen the best response.0dw:1433887281746:dw This is the diagram given. With the curved path being the path of the ball.

Curry
 one year ago
Best ResponseYou've already chosen the best response.0Wait I think catch.me is correct actually. The time it takes to get to the bottom is 1.42 seconds. So the Vy is 9.8*1.42. tan(30) = Vy/Vx. Giving us a value of 24 m/s. I understand why this way works. But I still don't understand why the other way doens't work.

IrishBoy123
 one year ago
Best ResponseYou've already chosen the best response.2@curry medal to @Catch.me would be fair. at time of writing, none.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0@radar yeah i should be 60 @Curry how did you calculate horizontal distance?

radar
 one year ago
Best ResponseYou've already chosen the best response.0dw:1434062799673:dw @Curry I used the law of sines. Sin 60/x = Sin 30/10. I'm not sure if that would of given me the horizontal distance, but that is what I used.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0The curve is parabola not straight line( angle is changing) vt= 14 m/s v0= 14 root 3 time = delat v/g=10/7 x= 20 root 3
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