Solve the problem using dimensional analysis. Every number must have a unit. Work must be shown. Conversion factors are in the table. Gold cost $8.00 per ounce. Determine how many grams you can purchase for $15.00.

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

the answer is the first electromagnet (a). this is because it has more coils around the ferromagnetic material. increasing the number of coils increases the surface area in which the metal interacts with the current in the coil. this enables more atoms in the metal to become aligned hence becoming more magnetized.