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Homework Statement
An object is shot from the origin with a velocity of 40.0 m/s at an angle of 55.0 degrees above the horizontal. What is the location of the object 3.00 seconds later?
Homework Equations
All 2D motion equations - too many to list Ex:
[tex] V_x = v_0x + a_x t [/tex]
[tex] V_y = v_0y + a_y t [/tex]
The Attempt at a Solution
What I am having trouble with is the 3.0 seconds later part. I am not sure how to approach this one. I have to find the x displacement and then the angle [tex] \theta [/tex] which is no problem to do when I know [tex] V_y and V_x [/tex].
So I tried this:
[tex] \Delta x = 40 cos(55)3.0 = 68.8m [/tex] , but none of the answer choices match this. So I must be doing something wrong. I also can't get a correct answer for [tex] V_y and V_x [/tex] with these I could plug them into the inverse tangent equation and get an angle. To find [tex] V_x [/tex] I do this:
[tex] V_x = 40 cos (55) = 22.9 [/tex]
for [tex] V_y [/tex] I do this :
[tex] V_y = 40 sin (55) - (9.80)(3.0^2) = -55.4 [/tex]
I am not sure that I am using the time variable correctly.