(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A toy cannon fires a .089kg shell with an initial velocity of 8.9 m/s at an angle of 56* above the horizontal. The shell's trajectory curves downward due to gravity, so at time t=.615s the shell is below the straight line by some vertical distance deltaH. Find this distance deltaH in the absence of air resistance. Answer in units of meters

2. Relevant equations

y_{f}=y_{i}+ v_{yi}t+1/2a_{y}t^{2}

x_{f}=x_{i}+ v_{xi}t+1/2a_{x}t^{2}

v_{yi}=v_{i}sin[tex]\vartheta[/tex]

v_{xi}=v_{i}cos[tex]\vartheta[/tex]

3. The attempt at a solution

So I have tried two different methods of approaching this problem but still no luck. Here is what I have:

v_{yi}=8.9m/s(sin56)=7.378434 m/s

v_{xi}=8.9m/s(cos56)=4.976816 m/s

[tex]\Delta[/tex]h=7.378434m/s(.615s)-4.9m/s^{2}(.615s)^{2}

=2.68443 m

This answer was rejected as incorrect so I tried another method. I figured that I could form a triangle with the given data with v_{i}as the hypotenuse and x was found using the following:

x_{f}=v_{xi}t

=4.976816(.615)=3.06074184 m

Using this I solved for y in a right triangle as usual with pythagorous at my disposal and obtained a length of 4.53774m which again was rejected.... Any insight as to where I am missing something? Thanks in advance.

Joe

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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