Field size may be defined geometrically or dosimetrically; geometric field size typically corresponds to the field as defined by the field light while the dosimetric field size corresponds to the 50% isodose line. 

TMR increases with:

1 Gy = _____.

Anthropomorphic phantoms incorporate various materials in order to stimulate the various tissues in the human body.  

The dose to air is found to be 1.2 Gy. What is the exposure?

The Mayneord F factor is used for dose calculation when the treatment SSD is different from the standard SSD.  

Kerma is made up of _____________ kerma and ______________ kerma.

The point of maximum dose is referred to as:

A treatment is planned using a single field at a distance of 100 cm and a 6 MV beam (Dmax=1.5 cm). In order to accommodate the target volume, the distance must be extended to 110 cm. The depth of the target is 3 cm. If the original PDD value at depth was 91.4%, what is the PDD value at a distance of 110?

If the dose to a target volume is 175 cGy (PDD = 88.5%), calculate the dose to an underlying structure located at a depth of 16 cm where the PDD is 36.4%.