A1.0 kg copper rod rests on two horizontal rails 1.0 m apart and carries a current of 50 a from one rail to the other.
the coefficient of static friction between rod and rails is 0.60.what are the
(a) magnitude
(b) angle (relative to the vertical) of the smallest magnetic field that puts the rod on the verge of sliding?

Which object is most likely represented by a dot?

Photons with the highest energy have the longest period

Cells in the nervous system have a potential difference of 70 mv across the cell membrane separating the interior of the cell from the extracellular fluid. this potential difference is maintained by ion pumps that move charged ions across the membrane. is this an emf? select the correct answer and explanation. 1)no. the ion pumps cannot separate charges; thus, they cannot create a potential difference. 2)yes. the ion pumps cannot separate charges, but they still can create a potential difference. 3)yes. the ion pumps can actively separate charge; thus, they can create a potential difference. 4)no. the ion pumps can separate charges, but they cannot create a potential difference.