Derive the law of conservation of charge from maxwell's equations. b express the electric field in terms of the scalar potential p and the vector potential a where b curl a. (note: for the general time-dependent case e is not equal to grad y alone.)

Suppose a wire with a current is pushed upward by a magnetic field. how would the wire move if the direction of the current reversed? explain your answer.

Global warming will produce rising sea levels partly due to melting ice caps but also due to the expansion of water as average ocean temperatures rise. to get some idea of the size of this effect, calculate the change in length of a column of water 1.00 km high for a temperature increase of 1.00ºc. note that this calculation is only approximate because ocean warming is not uniform with depth. (answer in ×10^{-3} −3 m)

What is the relationship between the direction of motion of the balloon and the wind currents