How do you find the cross-sectional area in geography?
Cross-sectional area (A in the formula) is the product of stream width multiplied by average water depth.
What is a cross-section diagram?
Cross-sections Geologic Cross Section: a diagram showing the structure and arrangement of rocks as they would appear in a vertical plane below the Earth’s surface. These diagrams provide a viewpoint as if you were looking from the side (or a side view).
What is a cross-section in a river?
River cross profiles show you a cross-section, taken sideways, of a river’s channel and/or valley at certain points in the river’s course. A channel cross-profile only includes the river whereas a valley cross-profile includes the channel, the valley floor and the sides of the valley.
What is the cross section of a river?
A cross profile shows a cross-section of a river’s channel and valley at a certain point along the river’s course. A – as the river flows downhill there is an increase in vertical erosion . The channel is shallow and narrow because there is not a lot of water in the channel.
How does the cross-section of a river change downstream?
As the river flows downstream it is joined by tributaries, increasing the volume of water, velocity and therefore its erosive power. This enables it to cut a deeper channel as it flows downstream. Downstream, the channel becomes wider as the gradient becomes more gentle leading to less vertical erosion.
How do you draw a cross-section of a river?
To draw the shape of a river valley, the line is best drawn to connect the highest point on either side of the valley, at right-angles to the river. 2 Put the straight edge of a piece of scrap paper along your cross-section line. Mark the beginning and end of the cross-section, and write down the grid references.
What is the cross profile of a river?
The cross profile of a river shows how the width and depth of the river valley and channel change as you travel downstream. Near the source of a river there is more vertical erosion as the river flows downhill, using its energy to overcome friction (A).
What is the meaning of cross section in physics?
In physics, the cross section is a measure of the probability that a specific process will take place when some kind of radiant excitation (e.g. a particle beam, sound wave, light, or an X-ray) intersects a localized phenomenon (e.g. a particle or density fluctuation).
What is the purpose of cross section?
A cross section is the shape that you create when you cut through or make a slice of an object. They allow us to see what’s inside an object. Some of the most famous cross sections are conic sections, cross sections are created by slicing a right cone in various ways.
Why does the cross profile of a river change?
In the upper course, the river erodes its bed by hydraulic action and abrasion. This enables it to cut a deeper channel as it flows downstream. Downstream, the channel becomes wider as the gradient becomes more gentle leading to less vertical erosion.