Computer hard drives are made of aluminum platters coated with a layer of magnetic material. Each tiny magnetic domain represents one bit of information (1 or 0).
A) How many such domains must a hard drive of 3 TB have (1 Byte = 8 bits)?
B) A typical drive has a round platter of 9.5 cm in diameter with a hole of 2.5 cm diameter at the center. Assuming the domain are squares, what is the length of their sides in such a drive?