Question 1: Describe the typical features you would expect to find at the source of a river in a mountainous region.

Answer: Features include a steep gradient, fast-flowing water, small channels, and possibly waterfalls or rapids. The source is often located in high-altitude areas such as mountains.

Question 2: Explain how a river’s velocity changes as it moves from its source to its mouth. Include at least two reasons for this change.

Answer: The velocity of a river generally decreases from source to mouth. This is because the river’s slope becomes gentler, and the channel width and volume of water increase, which reduces the flow speed.

Question 3: Identify and describe two landforms that are typically formed by the erosive action of a river in its middle course.

Answer: Two landforms are a meander, which is a winding curve in the river, and an oxbow lake, which forms when a meander is cut off from the main river channel.

Question 4: Explain the process of hydraulic action and how it contributes to river erosion.

Answer: Hydraulic action occurs when the force of the moving water compresses air into cracks in the riverbank or bed, causing the material to break apart over time. This process helps to erode the riverbanks and bed.

Question 5: Draw a simple diagram showing the cross-section of a river valley with a valley floor, sides, and a river flowing through it. Label the key features.

Answer: A correct sketch would show a V-shaped valley with sloping sides, a flat or gently sloping valley floor, and a river flowing along the base. Labels should include 'river,' 'valley sides,' 'valley floor,' and 'bank.'

Question 6: Describe the process of deposition and explain where in a river’s course it is most likely to occur.

Answer: Deposition occurs when a river loses energy and drops the materials it is carrying, such as sediments or rocks. It is most likely to happen in the mouth of the river or in areas where the river slows down, such as in a floodplain or a delta.

Question 7: Identify three environmental impacts that human activities can have on river systems.

Answer: Human activities can lead to pollution from industrial waste, increased flooding due to urban development and deforestation, and habitat destruction affecting aquatic and terrestrial wildlife.

Question 8: Explain how the presence of a dam upstream can affect the river’s flow and sediment transport downstream.

Answer: A dam upstream reduces the flow of water downstream, which can lead to sediment build-up behind the dam and reduced sediment flow further downstream. This can cause erosion of riverbanks and a loss of nutrients downstream.

Question 9: Sketch a diagram to illustrate the formation of a delta at a river’s mouth. Indicate the main processes involved.

Answer: A correct sketch would include a river depositing sediments as it enters a standing body of water, forming a triangular delta shape. Arrows should show the flow of water spreading out, and labels should include 'sediment deposition,' 'main river channel,' and 'delta landforms.'