Question

If the slice thickness is changed form 5 mm to 7 mm and all other parameters are held constant, ___ % more photons will be used in making the slice.

a. 30
b. 40
c. 60
d. 80

Answer 1

If the slice thickness is changed from 5 mm to 7 mm, the percentage increase in the number of photons used in making the slice is 40%.

Step-by-step explanation:

To calculate the percentage increase in the number of photons, we need to consider the relationship between slice thickness and the number of photons used. The number of photons used is directly proportional to the slice thickness. In this case, if the slice thickness is changed from 5 mm to 7 mm, the increase in slice thickness is 2 mm.

To calculate the percentage increase, we can use the formula:

Percentage increase = (Increase in slice thickness / Initial slice thickness) × 100%

Plugging in the values, we have: Percentage increase = (2 / 5) × 100% = 40%

Therefore, the correct answer is 40% (option b).