Final answer:
The line focus principle enhances spatial resolution and heat capacity by angling the target in radiography, allowing finer detailed imaging and better heat management.
Step-by-step explanation:
The advantage of the line focus principle is that it simultaneously increases spatial resolution and heat capacity. This principle is particularly important in the field of radiography. It works under the principle that the effective area of the focal spot becomes smaller when the target is angled to the incoming electrons; thus, finer detail can be captured in images. At the same time, the larger actual area of the focal spot that is struck by electrons can disperse more heat, thereby increasing the tube's ability to manage thermal load without damage.