Question

Consider separation of dust particles from gases in a cyclone separator. For a given particle size, the terminal velocity is maximum:

• A. at a location near the wall of the cyclone
• B. at an intermediate location between the centre and the wall of the cyclone
• C. at a location near the center of the cyclone
• D. at the wall of the cyclone

Hint:

In cyclone separators, particles experience the highest centrifugal force near the wall, which leads to the maximum terminal velocity.

Answer 1

The Correct Option is A

Step 1: Understanding the behavior of particles in a cyclone separator.
In a cyclone separator, the particles are subjected to centrifugal forces. The terminal velocity (velocity at which the particles no longer accelerate) is highest at the outermost part of the cyclone (near the wall). This is because the centrifugal force increases with the radius from the center of the cyclone, leading to higher velocities near the wall.

Step 2: Explanation of options.
- (A) At the wall of the cyclone, the centrifugal force is the highest, causing the particles to reach their maximum terminal velocity. - (B) and (C) These are locations where the terminal velocity is not at its maximum because the centrifugal force is lower compared to the outer regions of the cyclone. - (D) The wall of the cyclone is the most accurate location where maximum terminal velocity is achieved.

Final Answer: \[ \boxed{\text{A) at a location near the wall of the cyclone}} \]