Final answer:
The size of the IR (infrared) that should be used on wrist projections depends on the specific application and the desired level of detail. Generally, an IR with a wavelength range of 750 nm to 1000 nm is commonly used for wrist projections.
Step-by-step explanation:
The size of the IR (infrared) that should be used on wrist projections depends on the specific application and the desired level of detail. In general, an IR with a wavelength range of 750 nm to 1000 nm is commonly used for wrist projections. This range is within the near infrared region, which allows for good penetration into the skin and tissue. However, it is important to note that the specific size of the IR will also depend on the equipment being used and the imaging technique.