When a logarithm is taken of a physical quantity, what does the resulting value not have? Because of this...

## Step1: Understanding the concept of logarithm
### A logarithm is a mathematical operation that determines the exponent or power to which a base number (usually 10) must be raised to produce a given number. It is a way of expressing a number in terms of a power of another number.
## Step2: Understanding the concept of physical quantity
### A physical quantity is a quantity that can be measured and expressed in numbers. It has a unit of measurement associated with it. For example, time is a physical quantity and it is measured in seconds.
## Step3: Understanding the effect of logarithm on physical quantity
### When a logarithm is taken of a physical quantity, the resulting value is dimensionless. This is because the logarithm operation removes the unit of measurement from the quantity. Therefore, the resulting value does not have a unit.
## Step4: Importance of specifying the unit in the logarithm column
### Because the logarithm operation removes the unit of measurement from the quantity, it is important to specify the unit in the logarithm column. This is usually done by including the unit in the title of the logarithm column, for example, Log (time/s).