Gradually Varied Question 4: Calculate the critical depth corresponding to a discharge of 8m³/s in a rectangular channel of width 4m. Take g = 10m/s²

The top width and the depth of flow in a triangular channel were measured as 5 m and 1 m respectively. The measured velocity on the centre line of flow area at the water surface, 0.2 m and 0.8 m below the surface are 0.8 m/s, 0.6 m/s and 0.5 m/s respectively. Using two point method of velocity measurement, the discharge (in m3/s) in the channel is

In a 5 m wide rectangular channel, the velocity u distribution in the vertical direction y is given by u= 1.25y¹/6. The distance y is measured from the channel bed. If the flow depth is 2m, the discharge per unit width of the channel is