10. a 0.25-m-wide slab of 5052-o aluminum (k=210 mpa, n=0.13) (k=210 mpa, n=0.13) is rolled from a thickness of 30 mm to a thickness of 20 mm on a cold mill with a roll diameter of 600 mm. the coefficient of friction is 0.25. calculate the maximum roll pressure and required roll force. assume the slab width is constant during the process.

your answer is, orbit around the nucleus

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.