Final answer:
To calculate the average velocity of a stream given its dimensions and flow rate, use the formula Q = Av and solve for v. However, a flow rate of 100,000 m³/s for a stream 10 m wide and 2 m deep seems unreasonable, indicating an error or inconsistency.
Step-by-step explanation:
The question relates to the calculation of the average velocity of water in a stream, given certain dimensions and the flow rate during an event like spring runoff. The flow rate (Q) can be used along with the cross-sectional area (A) of the stream to calculate the average velocity (v) using the formula Q = Av. In the scenario where a mountain stream is 10.0 m wide and averages 2.00 m in depth with a flow rate of 100,000 m³/s, we use A = width × depth = 10.0 m × 2.00 m to find the area, and then rearrange the formula to solve for v as v = Q / A. However, without the actual calculations, we can immediately spot that the flow rate of 100,000 m³/s is not reasonable for a stream of this size, hinting at an unreasonable result or an inconsistency in the premises.