Abar of brass is used to conduct heat between two heat reservoirs at temperatures of 20 degrees c and 80 degrees c. the bar has a square cross section with edge 1.0 cm. the length of the bar is 70 cm. what is the rate of thermal conductivity?

A-4.60 μc charge is moving at a constant speed of 6.80×105 m/s in the +x−direction relative to a reference frame. at the instant when the point charge is at the origin, what is the magnetic-field vector it produces at the following points.

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?

Zeros that follow non-zeros numbers and are also to the right of a decimal point are significant