When a solute can't be dissolved in a solvent what is it called called?

What produces a record of seismic waves? richter scale seismogram barometer seismograph

Along the line connecting the two charges, at what distance from the charge q1 is the total electric field from the two charges zero? express your answer in terms of some or all of the variables s, q1, q2 and k =14ï€ïµ0. if your answer is difficult to enter, consider simplifying it, as it can be made relatively simple with some work.

How can you increase the strength of an electromagnet?