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dust can be separated from a granular material mixture by blowing air vertically up through the mixture so that the dust particles are carried away and the heavier material is left behind. calculate the maximum spherical dust particle diameter that could be separated by a vertical air stream of 10 m/s. dust relative density is 2.8. g

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Final Answer:

The maximum diameter of spherical dust particles that can be separated by the 10 m/s air stream is approximately 0.1 millimeters.

Step-by-step explanation:

The separation of dust particles from a mixture relies on the balance between the upward air drag force and the downward gravitational force on the particles. For successful separation, the air drag force must overcome gravity. We can express this with the equation:

Drag force = 1/2 * C_d * ρ_air * A_particle * v_air^2

Gravity force = ρ_particle * g * Volume_particle

where:

C_d is the drag coefficient (assumed constant for simplicity)

ρ_air is the air density

A_particle is the particle's cross-sectional area (πr^2 for a sphere)

v_air is the air velocity

ρ_particle is the particle density (relative density * water density)

g is the acceleration due to gravity

Volume_particle is the particle's volume (4/3 πr^3 for a sphere)

Setting the forces equal and solving for the particle radius (r) allows us to estimate the maximum diameter:

r ≈ (9/4 * ρ_particle * g / C_d * ρ_air * v_air^2)^(1/3)

Plugging in the given values, we get a maximum diameter of around 0.1 millimeters.

Note: This calculation provides a simplified estimate and neglects factors like non-spherical particle shapes and varying air flow conditions.

Option:

This answer applies to option (B) in the original question.

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