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The total drag is a sum of the skin drag and the pressure drag. Which among of the following options, states the correct formula for skin drag and pressure drag? (Here µ stands for dynamic viscosity of fluid, D stands for diameter of the sphere and U stands for velocity of flow of fluid.)

The total drag is a sum of the skin drag and the pressure drag. Which among of the following options, states the correct formula for skin drag and pressure drag? (Here µ stands for dynamic viscosity of fluid, D stands for diameter of the sphere and U stands for velocity of flow of fluid.) Correct Answer 2πµDU, πµDU

Total drag is accounted by two thirds of the skin drag and one third of the pressure drag. Skin drag, also called friction drag, is due to the friction offered by the fluid, while pressure drag is due to the pressure difference between the sides of the sphere.

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