A particle moves along the x-axis so that at any time 0
I have to use a graphing calculator, but I am still unsure of how to do particle motion problems.
\[\large{v(t) = (t-2)^2 \cos(2t)}\] The particle will change its direction everytime sign of v changes
http://www.wolframalpha.com/input/?i=graph+%28t-2%29%5E2*cos%282t%29+++from+0%3Ct%3C5
Now I never used graphing calculator. So, you will have to tell me this: Does graphing calculator draw a graph ? A stupid question though
*My question is stupid
yes, it will and it will also draw derivatives
Okay so draw the graph and see the signs
your question is fine, I am just well verse on the graphing calculator
I typed it into wolframalpha if you want to look at the graph
Okay I am going to use wolfram to plot the graph
I want to say 3 times
+ -> - -> rest -> + -> -
I am not sure whether rest would affect the answer or not
yes I am not sure about the "rest" either. I never studied physics
Okay lets see in physical conditions.
well my next question leads me into v ' (2) and to describe the motion so my answer would be v ' (2)=0 and the particle is at rest
\[\large{v'(t) = 2(t-2)\cos(2t) - 2(t-2)^2\sin(2t)}\] Yeah v'(2) = 0
wow you are good. I took the easy way out and just let the calculator solve it. and yes the calculator can find derivatives at a point
Thanks :)
last question, average acceleration, do I take the integral for that?
Yeah
\[\frac{ 1 }{ b-a}\int\limits_{a}^{b}v(t)dt\]
Yeah
or is it the function a(t)dt?
I don't think there is much difference
ok let me calculate both since I can do it on my calculator
Yeah that would do :)
.2819 is for v(t)dt .84496 is for a(t)dt
I really don't like particle motion
Here! here! :D
Okay figured out a(t) dt is correct
Integral gives area
Area of v(t) and t curve is total displacement and thus will give average velocity
Area of a(t) and t curve would give net change in velocity and thus average acceleration
ok thanks, I went to google it and got even more confused
Google's one of few disadvantages :)
true
thank you so much, I hate particle motion. Maybe I should go do over type of homework instead and skip this nonsense. I wish I had taken physics at some point because it really gives me a lot of heartache.
Your welcome :)
Join our real-time social learning platform and learn together with your friends!