Throwing a dart from a roof - Velocity

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A dart thrown horizontally from a rooftop has a flight time of 2.0 seconds and lands at a 53.1-degree angle with the ground. The initial vertical velocity is zero, and the final vertical velocity after 2 seconds is calculated to be 19.6 m/s using the equation Vf = Vi + at. The horizontal component of the final velocity (Vfx) is determined using the tangent of the angle, leading to a value of 14.7 m/s. This calculation confirms the speed at which the dart was thrown. The solution process is validated by the participants in the discussion.
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Homework Statement



A dart is thrown horizontally from a buildings rooftop. The dart's time of flight is 2.0 s. The dart sticks in the ground such that it makes a 53.1 degree angle with the ground.

With what speed was the dart thrown?

The Attempt at a Solution



I am studying for my final and i do not get this problem from one of my previous tests.

The answer is 14.7 m/s and i have no idea how to get it. Can anyone point me in the right direction.

Thank you :)
 
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Well if it is throw horizontally, then the initial vertical velocity is zero right? Using an equation of motion, what would be final vertical velocity when t=2?
 
Is the final vertical velocity when t=2 just 19.6 m/s

I got that from

Vf = Vi + at

oh so then from that the x component of the Vf will be the same as the velocity initial correct?

so

tan(53.1) = 19.6 / Vfx

Vfx = 14.7 m/s

Does that seem right?
 
Yes that looks correct.
 
Yay! thank you very much :)
 
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