The flow of a river at the lower course is slow because
Answer Details
The flow of a river at the lower course is slow because the gradient is greatly reduced.
The gradient of a river refers to the slope or steepness of the riverbed. At the upper course of a river, the gradient is generally steep, which means that the river is flowing downhill quickly. However, as the river moves towards the lower course, the gradient decreases, causing the river to slow down. This is because the river has deposited much of its sediment, which has built up the riverbed and created a gentler slope.
Additionally, the volume of water in the river also increases as it moves towards the lower course, which can also contribute to a slower flow. The increased volume means that the river has more water to move, and therefore it takes more time for the water to flow through the channel.
In summary, the slow flow of a river at the lower course is due to the combination of a reduced gradient and an increase in the volume of water.