Need help with calculating gradient!! (1 Viewer)

Jessa100

New Member
Joined
Aug 4, 2011
Messages
13
Gender
Undisclosed
HSC
2012
Need help with calculating gradient!!

I have a geography skills test coming up and am starting to practise however I am having trouble with gradient. If anoyone can help me with this I will be tremendously grateful!! How do you calculate the gradient on a topographic map and convert it into a 1:x ratio?? Thanks :)
 

RivalryofTroll

Sleep Deprived Entity
Joined
Feb 10, 2011
Messages
3,805
Gender
Male
HSC
2013
Uni Grad
2019
Here are some key or notable notes on geographical gradient:
Gradient is a measure of slope of the land.
Knowing the gradient of a slope is important to road and rail building, chances of erosion, vegetation and cultivation, house building, etc.
Gradient expresses the average slope between two points.
Gradient can be classified according to the steepness of the slope.

The gradient of a slope can be measured on a topographic map -
1. Calculate the difference in height (also known as rise) between the two points (A and B)
Example:
A is 20 Metres High
B is 145 Metres High
B - A = 145 - 20 = Rise/Height Difference
Difference in Height is 125 Metres

2. Calculate the horizontal distance between A and B using the provided scale.
Let's just say that you found out that the distance was 1.3km, so you need to convert this into the same units as the difference in height.
This changes into 1300 Metres? Agreed?

3. Gradient Formula
Gradient = Difference In Height/Horizontal Distance Or Rise/Run or Point Y - Point X/Distance
If you're mathematical, draw a right-angle triangle then think of it like this:
The difference in height is the opposite side to the angle of elevation, the run/distance is the adjacent to the angle of elevation.
Hence, the hypotenuse is the slope.
So think of it as tan theta or opposite/adjacent.

BUT, in geography you must express it in words so a numerical answer may cause loss of marks.
The gradient can be expressed as a fraction with one as the numerator OR a ratio like you stated.
Gradient = 125/1300 (Divide top and bottom by 125) = 1/10.4
The gradient between A and B is one in 10.4.
THEREFORE, that is, for every 10.4 Metres travelled, there is a rise of one metre.
The line above is your FINAL answer which should be full marks!

It is very easy after you do it once or twice!

EDIT: You may also need to state in your answer, whether that answer shows a moderate, steep or very steep slope.

RE-EDIT: If you have any further problems, you may MSG me or reply again to this thread.
 
Last edited:

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top