Three sleds are being pulled horizontally on frictionless horizontal ice using horizontal ropes (Figure 1). The pull is of magnitude 160 N

the minimum amperage that the current in this wire would have to have so that its weight is completely supported by the magnetic force due to earth's field, assuming that no other forces except gravity act on it

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