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Two adjacent layers of water move parallel to each other with a relative speed of 8 cm/s. If the separation between the layers, measured perpendicular to their motion, is 0.1 cm, what is the velocity gradient?
- 80 s⁻¹
- 50 s⁻¹
- 50 s⁻¹
- 40 s⁻¹
Correct answer: 80 s⁻¹
Solution
Velocity gradient = relative speed / separation = 8 cm/s / 0.1 cm = 80 s^-1. (Options 1 and 2 are also duplicate values.)
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