What is the formula for cross-sectional area?

Therefore, if a cross section is parallel to the top or bottom of the solid, the area of the cross-section is l × w. If the cutting plane is parallel to one of the two sets the sides, the cross-sectional area is instead given by l × h or w × h.

How do you find the area of a rod?

The formula to calculate the total surface area of a cylinder is given as, the total surface area of cylinder = 2πr(h + r), while the curved surface area of cylinder formula is, curved/lateral surface area of cylinder = 2πrh, where ‘r’ is the radius of the base and ‘h’ is the height of the cylinder.

How do you find the cross-sectional area of a river?

Cross-sectional area (A in the formula) is the product of stream width multiplied by average water depth.

What is the meaning of 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. The channel is at its widest and deepest.

How do you find the cross sectional area of a river?

Why does the cross sectional area of a river increase downstream?

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.

How do you measure the cross-section of a river?

Using a tape measure, hold one end at the point where the water meets the bank one side of the channel. Ensure the tape is not twisted pull the tape measure across the river and measure to the point where the water meets the bank directly opposite.

How do you describe 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. Near the source of a river there is more vertical erosion as the river flows downhill, using its energy to overcome friction (A).

How does the cross profile of a river change as it moves 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.