Athin disk with a circular hole at its center, called an annulus, has inner radius r1 and outer radius r2. the disk has a uniform positive surface charge density σ on its surface.

What is the difference between electrically neutral objects and electrically charged objects

Matter is needed to transfer thermal energy bya. conductionb. convectionc. radiation d. both a & b.

During the experiment if you could triple the breakaway magnetic force with all other quantities left unchanged, what is the new value for the critical velocity if it was v0 (initial velocity), initially? (b) now if you halved the radius with all other quantities left unchanged, what is the new critical velocity if it was v0 (initial velocity), initially? (c) if during the experiment, critical velocity quadrupled with all other quantities left unchanged, what is the new breakaway force if its magnitude was initially f0,?