Question 1: Describe the main stages of a river's course from its source to its mouth.

Answer: The river begins at the source, often in upland areas, where it is typically narrow and flows quickly. As it moves downstream, it widens and slows, forming features like floodplains. Near the mouth, it deposits sediment as it enters a larger body of water like a sea or ocean.

Question 2: Explain the process of erosion that occurs on the outside of a river bend.

Answer: Erosion occurs on the outside of a bend because the water flows faster there, wearing away the riverbank through hydraulic action and abrasion, leading to the formation of a river cliff.

Question 3: Identify and describe two features formed in the middle course of a river.

Answer: In the middle course, features such as meanders (bends in the river) and slip-off slopes (deposits of sediment on the inside of bends) are common. These features develop due to continued erosion and deposition.

Question 4: Draw a cross-section of a river valley showing the river, valley sides, and the floodplain. Label each part.

Answer: A correct sketch should show a valley with steep sides (valley sides), the river flowing along the bottom, and a flat area on either side of the river (floodplain). The river might have a small channel with some sediment deposits.

Question 5: What is the difference between hydraulic action and abrasion in river erosion?

Answer: Hydraulic action involves the force of water hitting the riverbank and wearing it away. Abrasion occurs when the river carries sediment that scrapes and grinds against the bed and banks, eroding them.

Question 6: Explain how a delta is formed at the mouth of a river.

Answer: A delta forms when a river deposits large amounts of sediment as it slows down upon entering a standing body of water, causing the sediment to build up and form land that fans out into the sea or lake.

Question 7: Describe what a waterfall is and how it forms in a river.

Answer: A waterfall occurs where a river flows over a hard rock layer that overlays softer rock. The softer rock erodes faster, creating a steep drop or plunge pool, resulting in a waterfall.

Question 8: Identify and explain two ways in which human activities can impact a river's natural features.

Answer: Human activities such as dam construction can alter river flow and sediment transport, while urban development increases pollution and runoff, which can lead to habitat destruction and erosion of riverbanks.

Question 9: Describe how a meander develops in a river's middle course.

Answer: A meander develops as the river erodes the outer banks of bends and deposits sediment on the inner banks, gradually creating a winding, sinuous shape.

Question 10: Explain what is meant by the term 'river velocity' and how it changes from the source to the mouth.

Answer: River velocity is the speed at which water flows in the river. It tends to be faster near the source due to steeper gradients and decreases downstream as the river widens and slows down.