The earths orbit

is an ellipse
is a circle
causes day and night
goes around the moon

"why is graphite used instead of gold or copper wires to conduct electricity in very hot situations such as an industrial kiln? " that's the question, but the thing is, i don't even understand what an "industrial kiln" xd assistance would be < 3

Two identical small charged spheres are a certain distance apart, and each one initially experiences an electrostatic force of magnitude f due to the other. with time, charge gradually leaks off of both spheres. when each of the spheres has lost half its initial charge, the magnitude of the electrostatic force will be

An electron and a proton have the same kinetic energy upon entering a region of constant magnetic field and their velocity vectors are perpendicular to the magnetic field. suppose the magnetic field is strong enough to allow the particles to circle in the field. note: you'll need to look up the masses for an electron and proton. 1) what is the ratio of the radii of their circular paths rp/re?