
#1
May810, 05:43 PM

P: 365

1. The problem statement, all variables and given/known data
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? 3. 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 :) 



#2
May810, 06:10 PM

HW Helper
P: 6,214

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?




#3
May810, 06:36 PM

P: 365

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? 



#4
May810, 06:44 PM

HW Helper
P: 6,214

Throwing a dart from a roof  Velocity
Yes that looks correct.




#5
May810, 06:48 PM

P: 365

Yay! thank you very much :)



Register to reply 
Related Discussions  
a dart player, standing 3.2m away from the darboard... thorws a dart horizontally....  Introductory Physics Homework  2  
Solve A Question in 2D Motion A dart player throws a dart horizontally at a spee  Introductory Physics Homework  4  
Kinematics: Throwing ball up the building with unknown initial velocity  Introductory Physics Homework  4  
velocity of throwing a ball  Introductory Physics Homework  4  
Throwing a ball from the roof of a building...  Introductory Physics Homework  4 