Spirals - Archimedean, logarithmic, hyperbolic and clothoid
[20/70%]Find the derivative of the following implicitly defined function: (logarithmic spiral).
Find the radius of curvature of the curve given by the following polar equation: the Archimedean spiral .
Find the radius of curvature of the curve given by the following polar equation: the logarithmic spiral .
Find the angle between the tangent and the polar radius of the point of tangency for the following curves:
the spiral of Archimedes ;
the hyperbolic spiral ;
the logarithmic spiral ;
the cardioid ;
the arc of the lemniscate of Bernoulli .
Find the condition on the parameter of the logarithmic spiral under which its evolute coincides with the spiral itself.
Prove that for points of the Archimedean spiral , as , the difference between the length of the radius vector and the radius of curvature tends to zero.
Prove that under the conditions of Problem 94 the center of curvature moves along a curve tending to coincide with the circle .
Prove that the centers of curvature at points of the Archimedean spiral lying on one ray are located on an ellipse whose semi-axes do not depend on the choice of ray.
Plot the graph of the function in polar coordinates:
(hyperbolic spiral);
(logarithmic spiral);
;
.
Find the area of the sector , bounded by the curve:
(Archimedean spiral);
(hyperbolic spiral);
(logarithmic spiral).
Find the area of the figure bounded by the -th turn of the Archimedean spiral
and a segment of the polar axis.
Find the area of the figure bounded by a segment of the polar axis and two turns of the spiral corresponding to the values of the polar angle and :
;
.
Find the length of the curve:
(clothoid);
.
Find the length of the arc of the curve:
(logarithmic spiral);
(cardioid);
;
;
.
Prove that the lengths of the arcs of successive turns of the logarithmic spiral
form a geometric progression, and find its common ratio.
Let be the length of the arc of the logarithmic spiral
Find .
Find the length of the arc of the curve:
;
;
.
(Archimedean spiral.) A ray rotates about a point with constant angular velocity . A point moves along it with constant speed . Set up the equation, in polar coordinates, of the curve traced by the point , if at the initial moment of motion the ray coincides with the positive direction of the abscissa axis, and the point with the origin . Sketch the resulting curve.
Prove that in the preceding problem the Archimedean spiral is tangent to the rotating ray at the initial moment of time.
Prove that the Archimedean spiral is not an algebraic curve.