Question

The mass of material that can be fed per unit time to a unit area of the screen is called as

• A. Effectiveness of the screen
• B. Capacity of the screen
• C. Ability of the screen
• D. Productivity of the screen

Hint:

Screen capacity is the mass flow rate per unit area (e.g., kg/s/m²) that a screen can handle, a key parameter in designing screening operations.

Answer 1

The Correct Option is B

Step 1: Understand the definition in the context of screening. 
The question refers to the mass of material that can be fed per unit time to a unit area of a screen. This is a measure of how much material a screen can process, which is a key performance metric in screening operations:
Mass per unit time: This indicates the rate of material flow (e.g., kg/s or tons/hour).
Per unit area: This normalizes the flow rate to the screen’s area (e.g., kg/s/m²), making it a specific measure of throughput. 
Step 2: Identify the correct term. 
Effectiveness of the screen: This typically refers to how well the screen separates particles (e.g., the fraction of desired material that passes or is retained), not the rate of material fed.
Capacity of the screen: In screening, capacity is defined as the maximum mass of material that can be fed per unit time per unit area of the screen without overloading it. This directly matches the description in the question.
Ability of the screen: This is not a standard term in screening terminology.
Productivity of the screen: While productivity might imply output, it is less specific than capacity and not the standard term for this definition. 
Step 3: Evaluate the options. 
(1) Effectiveness of the screen: Incorrect, as effectiveness relates to separation efficiency, not the rate of material fed. Incorrect.
(2) Capacity of the screen: Correct, as capacity is the standard term for the mass of material fed per unit time per unit area. Correct.
(3) Ability of the screen: Incorrect, as this is not a recognized term in screening. Incorrect.
(4) Productivity of the screen: Incorrect, as productivity is not the precise term for this definition; capacity is more specific. Incorrect. 
Step 4: Select the correct answer. 
The mass of material that can be fed per unit time to a unit area of the screen is called the capacity of the screen, matching option (2).