Using magnetostatic pressure on a small patch of a uniform surface current of density k [current/width] why can we not analogous argument as griffiths did for electrostatic pressure, derive a formula for an regard this pressure [force/area] as being able to do work on the moving charges?

two charges are fixed in place on the x-axis as shown. the charge at x = 0 is negative and has magnitude q = 2 μcoulombs (1 μcoulomb = 10-6 coulombs). the charge at x = d, (d = +12 cm), is positive and has magnitude q = 4 μcoulombs. find a point x = xo along the x-axis at which the electric field is zero.

we need to know the time interval during which the force acts. impulse of force = momentum change

find the surface area of the sphere to the nearest square unit. use a calculator.

a. 254 in.2

b. 64 in.2

c. 127 in.2

d. 1,018 in.2

+15-35=-20

going in opposite directions