it is the diameter
One. The line of symmetry for a 180 degree arc (a semicircle) is the line that bisects the arc.
semicircle
semicircle
The measure of the central angle divided by 360 degrees equals the arc length divided by the circumference. So 18 degrees/360 degrees=arc length/(9 feet*2pi). 1/20=arc length/18pi feet; arc length=9pi/10 feet. It's refreshing to answer a question that is written with grammatical accuracy!
The complete arc of a semicircle is 180 degrees
Semicircle
it is the diameter
One. The line of symmetry for a 180 degree arc (a semicircle) is the line that bisects the arc.
At the center of the semicircle, the electric field due to the straight part of the rod will cancel out because of the symmetry. The electric field at the center of the semicircle is only due to the curved part, so you can treat the semicircle as an arc of a circle with charge distributed along its length. You can then calculate the electric field using the formula for the electric field of a charged arc of a circle.
minor arc
semicircle
Major arc.
semicircle
The measure of the central angle divided by 360 degrees equals the arc length divided by the circumference. So 18 degrees/360 degrees=arc length/(9 feet*2pi). 1/20=arc length/18pi feet; arc length=9pi/10 feet. It's refreshing to answer a question that is written with grammatical accuracy!
A semicircle.
Major arc is the longer of two arcs.