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EvoN1020v

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Posts posted by EvoN1020v

  1. Hello guys I'm a bit stumped here - why is [math]a_B[/math] tangential to the right along the x-axis as seen on bottom of the attached photo. I understand that velocity is zero at point B but why is acceleration tangential along x-axis instead of normal? If the bar is falling downward at center G then it has a path about B right? So B should have normal acceleration to the right instead of tangential. Maybe someone can explain that better for me. A bit frustrated here and thanks in advance.

    post-2249-0-25953100-1476233497_thumb.png

  2. If it was a test or assignment it would depend on who is marking it. Just my opinion, but it is better to circle the answers to the questions than double them, even if it somewhat makes sense to do so by adding "at A" and "at B". It would be even more important if a mistake was made and you did not get the right answers.

    Yeah either way I'm confident with my calculations. I only care about the "process" not the answer. Thanks guys!

  3. I was just wholly glad that Hillary stood her ground and fired some some nice facts back to Trump's face. I was smiling slightly inside but I can tell you that Trump made himself a "believable" candidate for people that aligns with his views. Trump was acting like a bully with his cocked head, scorn look and frown, lifting his shoulders occasionally, periods of intrupption and talking over the talk host Lester Holt. I thought Lester did a fantastic job, much better than the last moderator. Holt made Trump clarify some of things that he said, and I wondered a couple of times if Trump was acting like he did because Hillary is a woman. He even admitted during the presidential debate that he didn't pay any federal taxes for the last 15 years! In close, Hillary portrayed a wise choice and I hope she prevails but at the same time, I have a bad feeling that Trump COULD and MAY win. It is literally scary.

    Also you guys should check out CNN's Fact Checkers of the presidential debate and it says that Trump lied more than Clinton. Does a sane person want him as US president? Unfortunately we can't take common sense for granted so there will be people that will vote for him regardless - just because he has lots of money. So irrational.

  4. Yeah - but I made the same mistake EvoN made - after pointing he was using only one set of wheels I used only one wheels worth of thrust

    Here's a screenshot of calculations that I did yesterday. I put down 2 Fb for friction force at both back wheels and 2 normal reactions at each A and B. Is it good?

    post-2249-0-30059800-1475009457_thumb.jpeg

  5. I thought that would be enough of a hint. A quote from the question

     

    "and the normal reaction at EACH of the TWO wheels at A and B respectively"

     

    I make that four wheels. Your answer spreads a normal force equalling the force of gravity in the opposite direction over two wheels - one at the front and one at the back

    Yeah that was where I got struck on - the wording of the question. I did my calculations and I hope this is right: [math]F_B=4,500N, B_y=5,576.8N, and A_y=1,780.7N[/math]. If you want the TOTAL reactions at each A and B then just multiply Ay and By by two.

  6. Have you ever took Linear Algebra? It teaches you vectors in 3D space and how to define them. It's a very benefical course. The most basic idea is that you plot a point following the x,y,z axis. Also, do you know the right-hand rule? It tells you which direction the x, y, or z axis is going.

     

    If you have other questions, please don't hesitate to ask.

  7. I know that the intregation of [math]\frac{sinx}{cos^2x}[/math] is [math]secx[/math].

     

    But I'm not sure how to get to the answer. I started off by using the trigonometric identity: [math]cos^2x + sin^2x = 1[/math].

     

    Therefore, [math]\frac{sinx}{1-sin^2x}[/math]. Now what?

  8. I have heard this way: Undersized tires goes faster than the accuracy of the speedometer.

     

    i.e. Speed of the undersized tires: 140 mph.

    Speedometer reading: 100 mph.

     

    A friend have told me this story as her husband was caught by the police with a speeding ticket. He protested that he was going at 100 mph, while the police's laser gun read 140 mph. He had a friend who is a policeman and they did a private test. The first policeman was right, as the tires were going faster than what is said on the speedometer. The husband didn't want to buy the correct size of tires because bigger tires are more expensive than smaller tires. Who knows it might be more benefict that you buy the correct size tires than being caught with loads of speeding tickets? :)

  9. If you are swinging the rope vertically, then the pendulum at the bottom has the greatest tension. ([math]Tension = ma + Fg[/math]). (Note: In circular motions, [math]F=ma[/math] always is [math]F=\frac{mv^2}{r}[/math]).

     

    If you are swinging the rope horizontally, the tension is equally all way around.

  10. So you don't care about anything that doesn't directly effect your little life?

     

    What narrow horizons you must have.

     

    Yup, it's the same issue with gay marriages. Gay people don't bother me so I didn't care if gay marriages were legalized or not.

  11. I don't care if Saddam was executed or not, because he doesn't bother or alter my life in any ways.

     

    And don't say, "What if Saddam blowed this city?" questioned by my girlfriend. I told her that he would never blow this place because it's a small city, and he got no enemies here.

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