Can you just give me a hint for how to solve this problem?

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Homework Help Overview

The discussion revolves around a geometry problem involving circles and squares. The original poster is trying to determine the radius of smaller circles that fit within a larger circle of radius 1m, given that the diagonal of a small square is also mentioned. Participants are exploring the relationships between the dimensions of the shapes involved.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants suggest labeling the diagram to clarify known dimensions and relationships. There is a focus on understanding the geometry of the situation, particularly regarding the diagonals and the dimensions of the squares and circles. Some participants express confusion about the diagonal's length and its implications for solving the problem.

Discussion Status

There has been a productive exchange of ideas, with participants offering hints and exploring different interpretations of the problem. Some have proposed using right triangles to relate the dimensions, while others have shared their methods and reasoning. The discussion is ongoing, with no final consensus reached yet.

Contextual Notes

Participants are working within the constraints of a homework problem, which may limit the information available and the methods they can use. There is an emphasis on understanding the geometric relationships rather than arriving at a final answer immediately.

HAF
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Mentor note = moved to homework hence no template

Good evening everyone. I have a problem with solving this problem. I just don't know where to start. Can you please just "bounce" me somehow?

The radius of the big circle is 1m. What is the radius of the small ones?

The only thing I found out is that the diagonal of the small square is 1m. Nothing else.

Can you help me please?

Thank You
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HAF said:
Good evening everyone. I have a problem with solving this problem. I just don't know where to start. Can you please just "bounce" me somehow?

The radius of the big circle is 1m. What is the radius of the small ones?

The only thing I found out is that the diagonal of the small square is 1m. Nothing else.

Can you help me please?

Thank You
View attachment 227081
I don't think it is correct to say that the diagonal of any in this diagram square is 1. I suggest that you label the picture with what you know already. For example, choose one quadrant containing a small circle and label all of the radii of the small circle as having length ##r##. Label the radius of the large circle in that quadrant as having length 1. Now look at the small square formed by the quadrant boundaries and the large square. What is the length of its diagonal?
 
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tnich said:
I don't think it is correct to say that the diagonal of any in this diagram square is 1. I suggest that you label the picture with what you know already. For example, choose one quadrant containing a small circle and label all of the radii of the small circle as having length ##r##. Label the radius of the large circle in that quadrant as having length 1. Now look at the small square formed by the quadrant boundaries and the large square. What is the length of its diagonal?
So the diagonal of the square in the middle is not 1m? If you are correct than I'm completely lost. Help me please. Can you give me some hints for solving this problem?
 
HAF said:
So the diagonal of the square in the middle is not 1m? If you are correct than I'm completely lost. Help me please. Can you give me some hints for solving this problem?
I gave you some hints in my last post.
 
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tnich said:
I gave you some hints in my last post.
Is this thought correct?

1529357876458.jpg
 

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You've marked the angle at the top with an arc and a dot. I've never seen that notation. What does it mean?
 
jtbell said:
You've marked the angle at the top with an arc and a dot. I've never seen that notation. What does it mean?
I'm sorry for that. This is how I mark right angles.
 
OK, you have a right triangle. One of the sides adjacent to the right angle has length r. What's the length of the other side (adjacent to the right angle)?
 
jtbell said:
OK, you have a right triangle. One of the sides adjacent to the right angle has length r. What's the length of the other side (adjacent to the right angle)?
It's also r i think.
 
  • #10
So the hypotenuse of that triangle is...
 
  • #11
jtbell said:
So the hypotenuse of that triangle is...
2r^2
 
  • #12
I think that's the square of the hypotenuse. :oldwink:

Anyway, when you've got that sorted out, it gives you part of the radius of the large circle. What's the other part? The two parts have to add to 1.
 
  • #13
jtbell said:
I think that's the square of the hypotenuse. :oldwink:
Yeah I'm sorry. 2^1/2r
 
  • #14
HAF said:
2^1/2r
Or (√2)r. Click on the big "sigma" sign at the left, above the message box, and you'll get a palette of symbols that you can enter directly. I used parentheses to make clear that the square root applies only to the 2, not to the r.

Now you can "piece together" the radius of the large circle, which equals 1.
 
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  • #15
jtbell said:
Or (√2)r. Click on the big "sigma" sign at the left, above the message box, and you'll get a palette of symbols that you can enter directly. I used parentheses to make clear that the square root applies only to the 2, not to the r.

Now you can "piece together" the radius of the large circle, which equals 1.
Thank You very very much. I don't know why I didn't find it out by myself. I have to practise more.

Thank You guys. You are amazing.
 
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  • #16
Did this one get solved yet? I don't see a final answer from the OP @HAF . ## \\ ## The way I would do it basically uses 2 equations and 2 unknowns: ## r ## and a distance ## s ## from the origin to where the line ## x=0 ## intersects the top circle of radius ##r ##. It's fairly straightforward to write two equations with ## r ## and ## s ##. The one equation is very simple, and the second uses the properties of the 45 degree right triangle. ## \\ ## If you just consider one circle of radius ##r ##, the problem can be solved with x and y axes and a circle of radius ##r ## that fits into one quadrant. The distance ## s ## is then along the line ##y=x ##, from the origin to where the line first intersects the circle.
 
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  • #17
Charles Link said:
Did this one get solved yet? I don't see a final answer from the OP @HAF . ## \\ ## The way I would do it basically uses 2 equations and 2 unknowns: ## r ## and a distance ## s ## from the origin to where the line ## x=0 ## intersects the top circle of radius ##r ##. It's fairly straightforward to write two equations with ## r ## and ## s ##. The one equation is very simple, and the second uses the properties of the 45 degree right triangle. ## \\ ## If you just consider one circle of radius ##r ##, the problem can be solved with x and y axes and a circle of radius ##r ## that fits into one quadrant. The distance ## s ## is then along the line ##y=x ##, from the origin to where the line first intersects the circle.

Charles Link said:
Did this one get solved yet? I don't see a final answer from the OP @HAF . ## \\ ## The way I would do it basically uses 2 equations and 2 unknowns: ## r ## and a distance ## s ## from the origin to where the line ## x=0 ## intersects the top circle of radius ##r ##. It's fairly straightforward to write two equations with ## r ## and ## s ##. The one equation is very simple, and the second uses the properties of the 45 degree right triangle. ## \\ ## If you just consider one circle of radius ##r ##, the problem can be solved with x and y axes and a circle of radius ##r ## that fits into one quadrant. The distance ## s ## is then along the line ##y=x ##, from the origin to where the line first intersects the circle.

Yeah I solved it. I will definitely use your method also.

I solved it with the right angled triangle.

It's hypotenuse is (√2)r.

(√2)r + r = 1
r= 0,41m

Thank you for your tip Charles.
 
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  • #18
HAF said:
Yeah I solved it. I will definitely use your method also.

I solved it with the right angled triangle.

It's hypotenuse is (√2)r.

(√2)r + r = 1
r= 0,41m

Thank you for your tip Charles.
What you did is very similar to how I solved it. The hypotenuse that you computed to be ## \sqrt{2} r ## is what I called ## r+s ##. I saw that ## (r+s) \frac{\sqrt{2}}{2}=r ## because of the 45 degree right triangle. And then ## (r+s)+r=1 ##. Your solution is essentially the same thing, and perhaps a step quicker to the answer.
 
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  • #19
Charles Link said:
What you did is very similar to how I solved it. The hypotenuse that you computed to be ## \sqrt{2} r ## is what I called ## r+s ##. I saw that ## (r+s) \frac{\sqrt{2}}{2}=r ## because of the 45 degree right triangle. And then ## (r+s)+r=1 ##. Your solution is essentially the same thing, and perhaps a step quicker to the answer.
Most important thing is that we solved it. :)

Thank You
 
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