Fishing Line Physics: Finding Time and Velocity

AI Thread Summary
The discussion focuses on calculating the time and velocity of a fishing line cast from a bridge. The initial calculations involved breaking the motion into two parts: the time to descend to the level of the bridge and the time to hit the water, resulting in a total time of 3.74 seconds. The velocity upon impact was calculated to be 22.69 m/s. Participants noted that the use of two parts for time calculation may not be necessary and emphasized that projectiles are only influenced by gravity, not horizontal acceleration. Clarifications on the correct approach to solving the problem were provided to ensure accuracy.
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1. A fishing line is cast at 27 m/s at an angle of 33 degrees above the horizontal from the top of a 15m tall bridge. Find the time until the line hits the water below and find its velocity when it hits.



Homework Equations


x=xo+vot+1/2at2
v=vo+at



The Attempt at a Solution


I first found my component velocities and then the time by using the x=... equation above. I broke it up into 2 parts: the time it took to leave the bridge to the time it was level with the bridge on its downfall and i got 2.94s. Then i found the time it took to go from the point level with the bridge to the water and got .8s. I then added 2.94+.8=3.74s*.
To find the velocity i plugged my numbers into v=... equation above and got 22.69m/s*.

Someone please check and see if I did this correctly! I'm not sure if I was supposed to break it into 2 parts to find the time!
 
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A tip, when you preview the first post it puts the template in again, it helps to edit that out.

As for breaking it into two parts...my high school teacher described it as the tricycle method. There's a simpler way to do this.

However, why does your X component have acceleration in it? Remember projectiles are only affected by the force of gravity.
 
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