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Define the focus and the eccentricity of an ellipse?
A circle is perfectly round, and has one center. An ellipse is like a circle with TWO "centers", and each "center" is called a "focus". The plural of "focus" is "foci". Take a piece of string and tie a loop in each end. Put a pin through the loops, and hold it still in the center of the circle. Place the tip of your pencil at the center of the string, and you can draw a circle by keeping the string taut. Now take TWO pins, and put one pin at each end of the string; place the pins at some short distance apart, and hold them there. Place your pencil and draw, and the shape you draw will be an ellipse. The two pinpoints are the focuses, or foci, of the ellipse. Eccentricity is a measure of how far the ellipse varies from a circle. An ellipse with an eccentricity of zero _IS_ a circle, while an eccentricity of 1.0 is a straight line, with that string stretched out straight. In astronomy, every natural orbit is an ellipse.
How do you draw a circle with a pencil and ruler?
Use the ruler to measure the size of the circle you want - this will be a line all the way across the whole circle. Then, measure a piece of string with the ruler -- make this half the size of the original line. Use a thumbtack to tack the string in the spot you want the middle of your circle. Use a bit of tape to tape the other end onto your pencil (don't wrap it around or you will end up with a smaller circle!) Gently move the pencil around the thumbtack to make your circle.
How could you use a piece of string thumbtack and a pencil to construct a circle with radius AB?
Loop the string around the thumbtack and the pencil so that the distance from the tack to the pencil point is AB units. Fix the thumbtack to where you want the centre of the circle. Using the pencil, and with the string taut, mark its positions. These will lie on a circle with radius AB.
How long does a piece of string need to be to make a circle that is 32 inches in diameter?
pi*32 = 100.53 inches (approx)
How can one draw a perfect ellipse?
One can create a perfect ellipse using two pins on a piece of string and a pencil. Place the pins at opposite sides and then loop the string around them. Finally place the pencil in the loops and pull it around the pins to draw the ellipse.
How do you discover pi?
First draw a circle using a compass. Now, use a piece of string to help measure the circumference of the circle. Now measure the diameter of the circle. To discover Pi divide the circumference by the diameter.
A curve or circle in a piece of string?
That could be a loop.
What is the proper way to hold a circle divider when drawing a circle?
One can draw a circle by finding a round object that is the perfect size and trace the circle. One can also use a compass or string to draw a circle.
What is an arc of a circle?
It's the drawing you have if you began to draw a circle but the pencil point broke before you finished.
What is the circumference of circles?
The circumference is the length of the outside of the circle. For example, if you took a piece of string and made a circle with it, then laid the string straight, the length of the string would be the circumference. The circumference of a circle can be measured by doing two times the radius of the circle times the mathematical constant, pi.
How do you draw a circle?
To draw a perfect circle you will need a drawing compass. To draw a circle you will need a pencil and paper. Starting at the top centre of the paper, place the point of the pencil. Curving around to either the right or the left which ever preferred Guide the pencil all the way around to the starting position making sure that it is symmetrical all the way round. There you have your circle. You may want to use a drawing compass to assist you in drawing a perfect circle. If you do not have a drawing compass you can improvise with a thumb tack and some string. Tie one end of the string to the tack and pin it where you want the centre of your circle to be. Tie the other end to your pencil. Keep the string stretched and move the pencil around the pin to draw a circle. You can change the size of the circle by changing the length of the string.
Define the focus and the eccentricity of an ellipse?
A circle is perfectly round, and has one center. An ellipse is like a circle with TWO "centers", and each "center" is called a "focus". The plural of "focus" is "foci". Take a piece of string and tie a loop in each end. Put a pin through the loops, and hold it still in the center of the circle. Place the tip of your pencil at the center of the string, and you can draw a circle by keeping the string taut. Now take TWO pins, and put one pin at each end of the string; place the pins at some short distance apart, and hold them there. Place your pencil and draw, and the shape you draw will be an ellipse. The two pinpoints are the focuses, or foci, of the ellipse. Eccentricity is a measure of how far the ellipse varies from a circle. An ellipse with an eccentricity of zero _IS_ a circle, while an eccentricity of 1.0 is a straight line, with that string stretched out straight. In astronomy, every natural orbit is an ellipse.
What is a curve or circle in a piece of string?
it's a loop
How do you draw a circle with a pencil and ruler?
Use the ruler to measure the size of the circle you want - this will be a line all the way across the whole circle. Then, measure a piece of string with the ruler -- make this half the size of the original line. Use a thumbtack to tack the string in the spot you want the middle of your circle. Use a bit of tape to tape the other end onto your pencil (don't wrap it around or you will end up with a smaller circle!) Gently move the pencil around the thumbtack to make your circle.
How do you draw sailor jerry type tattoo flash?
what do you mean "how do you draw it"? that's like asking how you draw a circle. with a writing utensil and a piece of paper.
Why can't you draw a perfect circle?
Because it's physically impossible (general cases) to rotate our hand in exactly 360 degrees. My botany professor draws circles on board which makes us choke! He draws a circle with exactly 360 degrees- this is a special case, not seen everywhere. I draw perfect circles by using a compass, a stencil, or a piece of string.
How could you use a piece of string thumbtack and a pencil to construct a circle with radius AB?
Loop the string around the thumbtack and the pencil so that the distance from the tack to the pencil point is AB units. Fix the thumbtack to where you want the centre of the circle. Using the pencil, and with the string taut, mark its positions. These will lie on a circle with radius AB.
