Please help me with this. I just don't get it.
The average rate of chemical weathering of carbonate rock in an urban area is 2.1 x 10^-3 mm/yr. The depth of lettering of the tombstones shown in the table below was measured in 2010:
Date on Tombstone Age (yr)
1910 100
1921 89
1948 62
1958 52
1975 35
How much has the depth of the lettering been reduced on each tombstone?
To determine how much the depth of the lettering has been reduced on each tombstone, you need to calculate the difference between the initial depth (in 1910) and the current depth (in 2010). Here's how you can calculate it step by step:
1. Calculate the initial depth by multiplying the average rate of chemical weathering (2.1 x 10^-3 mm/yr) by the number of years between the date on the tombstone (1910) and the current year (2010).
Initial Depth = Average Rate of Chemical Weathering x (2010 - Date on Tombstone)
For example, for the first tombstone (1910 - 100 years = 1910), the initial depth would be:
Initial Depth = 2.1 x 10^-3 mm/yr x (2010 - 1910) years
2. Calculate the current depth by using the same formula but substituting the age of the tombstone in the current year.
Current Depth = Average Rate of Chemical Weathering x (2010 - Date on Tombstone)
For example, for the first tombstone (1910 - 100 years = 1910), the current depth would be:
Current Depth = 2.1 x 10^-3 mm/yr x (2010 - 1910) years
3. Subtract the current depth from the initial depth to determine the reduction in depth:
Reduction in Depth = Initial Depth - Current Depth
For example, for the first tombstone:
Reduction in Depth = Initial Depth - Current Depth
Repeat the steps for each tombstone with their respective dates to calculate the reduction in depth for all of them.