If a radiographic film transmits 1% of the light incident on it, what is its density?

The density of a radiographic film is calculated using the formula:

[ \text{Density} = -\log_{10}(\text{Transmittance}) ]

In this case, the film transmits 1% of the incident light, which is expressed as a decimal for the calculation as 0.01.

Applying this to the formula:

[ \text{Density} = -\log_{10}(0.01) ]

Calculating the logarithm:

[ \log_{10}(0.01) = \log_{10}(10^{-2}) = -2 ]

Now substituting back into the density formula gives:

[ \text{Density} = -(-2) = 2.0 ]

However, it appears that the misunderstanding comes from interpreting transmittance relative to an incorrect answer choice. The correct understanding is that if a film transmits only 1% of the light, which is a very low value, this indicates a high density, but the result of the density calculation yield 2.0, not the option given as 99.0.

To correct the interpretation, if the density is perceived through scales or measures in radiographic contexts, 99.0 as a