Suppose you are still a two-dimensional being, living on the same sphere of radius R. Show that if you draw a circle of radius r, the circle’s circumference will be C= 2(pi)Rsin(r/R) (3.62) Idealize the Earth as a perfect sphere of radius R = 6371 km. If you could measure distances with an error of ± 1 meter, how large a circle would you have to draw on the Earth’s surface to convince yourself that the Earth is spherical rather than flat?

Ryden, Barbara. Introduction to Cosmology (pp. 47-48). Cambridge University Press. Kindle Edition.

An ascending elevator, hanging from a cable, is coming to a stop. part a part complete identify all forces acting on the elevator from the list below. select all that apply. select all that apply. kinetic friction normal force tension weight static friction submitprevious answers correct part b draw a free-body diagram of the object. draw the vectors starting at the black dot. the location and orientation of the vectors will be graded. the exact length of your vectors will not be graded but the relative length of one to the other will be graded.