After we have our table of the foods we want every day, and the amounts, we are ready for our first engineering task. This is the most important task of all, determing how much space is required to grow that amount of food.
Looking at our food we now have a new table with a new column.
Table 2. Foods Required, Growing Rates and Meters required for growing food in Hydroponica.
The new column is called a production rate how many grams we can expect per square meter of growing space.
RATE- A rate is usually an amount of something based on time or space.
A speed for our cars or walking is measured in miles per hour.
A speedometer on a car is a measure of miles per hour, expressed as 40 miles/hour.
A waliking speed of a human is about 3 miles per hr. So how many hours will it take for a huan to walk 12 miles?
This is calculated with the equation
Hours to travel = miles to travel divided by rate of travel per hour.
H=12 miles/3 miles/hr
4 =12/2. Notice that the miles cancel out on the top and bottom of the fraction, leavig answer in hours.
Example 2.
A wage is money paid in dollars per hour. If you are making $5.00 and hour and work five hours, how much money do you make?
Equation is
Money made = Hours worked times how much money per hour
M=5 hours * $5.00 dollars/hour
$25.00 = h hours *$5.00/hour.
The units of hour calcel out and the answer is left in dollars.
The hours and dollars are called "Units" or the thing that is being measured, time and mney.
Production rate
For our first Hydroponica we need to estimate the amount of space required for each food.For this we need production rates per day
100grams/meter 2.
How many grams of food can be expected per day per square meter of growing space.
Sqaure meter or M2 is a measure of surface area.
PICTURE OF A SQUARE METER.
The M is an abbreviated for meter and the little two above the M is meaning it is a meter sqaured, or meter one side times meter on the other.
So the Production rate expresses how many grams are expected to be produced per meters 2.
PICTURE OF DAILY PRODUCTION FROM one square meter.
Production rates are based on experiments and observations of existng hydroponic gardens.
picture of hydroponnc greenhouse with tomatoes.
A commercial hydroponic greenhouse growing tomatoes relies on the production rate to determine how many tomatoes they can produce in a day.
For our model home we will trust these production rates to estimate how much space we need to get the food we want.
Estimate means a calculation of what might be expected.
Table with foods and amounts and production rates. Last column is all blank.
To determine how many meters are required for each food we need to
M 2 required is = amount required divdied by production rate om grams per m2
M=200gr/100gr/m2
Cancelling out the units means we have 2 m2 required.
So we make this calculation for each food and will end with a column of the table with the space required to grow all the food we need.
Task - To calculate each value for each food and place it into the table. Hint if needed.
Once you have calculated and have numbers for all the foods, go back and recalculate each number to make sure it is correct. This is checking for mistakes.
Once the calculations are done you can push the check button to see if you made any mistakes.
Corecting Errors
It might be that you have one or two numbers that are incorrect. This is probably because of an arthimetic error, numbers that are not divided properly.
Sideshoot math
Lots of Errors - If many of the numbers are incorrect there could be a misunderstanding of what we are doing. Sideshot video
Once the table has the vali=ues you need you are ready to go on to design a hydroponica.
Revised: 1 May 2021 |