Final answer:
The approximate minimum stream velocity needed to keep a particle in motion can be determined using the concept of fluid dynamics and the Reynolds number.
Step-by-step explanation:
The approximate minimum stream velocity needed to keep a particle in motion can be determined by using the concept of fluid dynamics and the Reynolds number.
The Reynolds number is a dimensionless quantity that represents the ratio of inertial forces to viscous forces in a fluid. For a particle to be kept in motion, the stream velocity should exceed a certain critical velocity, known as the critical Reynolds number velocity.
The critical Reynolds number velocity can be calculated using the formula: Vc = (D*v*rho)/mu, where D is the diameter of the particle, v is the velocity of the stream, rho is the density of the fluid, and mu is the dynamic viscosity of the fluid.
To find the approximate minimum stream velocity, substitute the values of D, rho, and mu into the formula and solve for v. Make sure to use consistent units for all the variables.