My rounding is off - can anyone try this?

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AI Thread Summary
The discussion centers on a user struggling with rounding errors in projectile motion calculations and seeking assistance before a deadline. Participants emphasize the importance of using the correct quadratic equation and not rounding intermediate values to improve accuracy. There is a suggestion to re-evaluate calculations from the beginning to avoid errors. The conversation highlights the need for clarity in the original query to receive more targeted help. Ultimately, the consensus is that without precise calculations, the user is unlikely to arrive at the correct answer.
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There are two points where the ball is at 6.3 height. You have to choose the point where the ball descends: the higher root of the quadratic equation.

ehild
 
What equation?
 
jaytm2291 said:
What equation?

The equation between y and x of a projectile.

ehild
 
I'm sorry you aren't being very clear. I didn't use a quadratic equation but I would like to. THis is due in about an hr. I have one try left. Please help me out instead of just giving me one word answers. Thanks.
 
What value of g you have used? And do not round v0 when you calculate this distance. I am not allowed to give the result, sorry, but I would say that your value is correct within 2 percent. My one is a bit higher than 2.4 m.

ehild
 
Last edited:
So I would have:

y=.33 tan(x)-4.9 (.33/(18.1 cos(x))^2

?
 
If your rounding is off, why don't you go through your calculations from the start and not round anything, at all. That way you will get the most accurate answer possible.

All you're asking here is for someone to do that for you, which they may do, but they can't give you the answer so it serves no purpose aside from to say your answer is wrong (which you know from the test).

You can easily go through it again from the start without rounding in well under an hour.

As it stands, I can go through it but my response will be no different to ehild. I can only tell you that your answer is incorrect and roughly how far out you are.

Jared
 
My calculations don't work for the real answer, but they do for the practice answer.
 
  • #10
jaytm2291 said:
My calculations don't work for the real answer, but they do for the practice answer.

In your original post you only mention your rounding is off, nothing is mentioned about the calculations. You should have been far more specific in the original post to stand a better chance at getting your required response.

From reading the OP, everyone will give the same response as per ehild and what I said in my previous post.

Jared
 
  • #11
jaytm2291 said:
So I would have:

y=.33 tan(x)-4.9 (.33/(18.1 cos(x))^2

?

This equation is wrong. Find the proper equation between the x and y coordinates of the projectile. The argument of the tangent and cosine is the launch angle with respect to the horizontal. It is given, 53 degrees. Why do you consider it unknown?

ehild
 
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