Recent content by A2Airwaves

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    Time derivatives of sin and cos phi

    Homework Statement By using chain rule of differentiation, show that: $$ \frac{\mathrm{d} sin\phi }{\mathrm{d} t} = \dot{\phi} cos\phi , \frac{\mathrm{d} cos\phi }{\mathrm{d} t} = -\dot{\phi} sin\phi , $$ Homework EquationsThe Attempt at a Solution I got this right for a homework problem...
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    Lagrangian equation for unconstrained motion

    Thank you for the correction, I was able to get the problem right :)
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    Lagrangian equation for unconstrained motion

    I'm currently working on the exact same question, and using : $$-\frac{\partial U}{\partial x} = F$$ I integrated ##F=-kx## and got : $$T= \frac{1}{2}m\dot{x}^{2},U = kx^{2}$$ Is this correct? Is T=(1/2)mv^2 always what you substitute in for a simple kinematics question?
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    How Do You Prove the Time Derivatives of Polar Unit Vectors?

    Thank you so much! My professor emphasized the geometric interpretation of the answers that I completely forgot about those definitions. Worked like magic, problem solved. By the way, is there a reason why you're writing ##\vec{i}## and not ##\hat{i}##? I'm used to ##\hat{i}## as a notation...
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    How Do You Prove the Time Derivatives of Polar Unit Vectors?

    Homework Statement Prove: $$\frac{d\hat{r}}{dt} = \dot{\phi} \hat{\phi }$$ and $$\frac{d\hat{\phi}}{dt} = -\dot{\phi} \hat{r }$$Homework EquationsThe Attempt at a Solution I solved this for an Analytical Mechanics assignment a month ago, and completely forgot how it goes.. $$\hat{r} ⊥...
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    Schools Aerospace engineering: strong colleges? is it a good major for me?

    Thank you Angry Citizen :) Texas A&M is absolutely in my list. Although money isn't my first priority, it is one of the reasons why I looked at aerospace engineering (or engineering itself). The thing is, now I am interested in astrophysics too.. actually it may be what I would like to do...
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    Schools Aerospace engineering: strong colleges? is it a good major for me?

    Hi, I'm a senior attending an international school and am thinking of pursuing an Aerospace engineering major. I think I am passionate enough for the major, but my problem is that I cannot find a great college that also will hopefully offer financial aid to me as an international applicant. So...
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    How Does Kinematics Influence Base Running Techniques in Baseball?

    Thank you for the help, it helped a lot! I hope I will get good results from the investigation.
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    How Does Kinematics Influence Base Running Techniques in Baseball?

    Homework Statement I'm currently working on doing an investigation on the relationship between kinematics and base running techniques in baseball. I'm trying to find out if "rounding the bases" is better than running straight to each base and turning, but I haven't found how I should preform...
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