Tyler (Taylor) standard screen scale: the ratio of open area (aperture area) of one screen to the next smaller screen is approximately

Introduction / Context:
Standard screen series (Tyler/Taylor) follow a geometric progression of aperture sizes so that test results and equipment selection are comparable. Understanding the step ratio between adjacent screens helps in interpreting cumulative size distributions and designing screening stages.

Given Data / Assumptions:

• The Tyler (often called Taylor) series uses the square root of 2 progression for aperture size.
• Open area of a single aperture scales with the square of the linear aperture dimension.

Concept / Approach:
In the Tyler series, each successive aperture size differs by a factor of √2 in linear dimension. Since area ∝ (size)^2, the ratio of aperture areas between successive screens is (√2)^2 = 2. Therefore, the open area of one aperture relative to the next smaller is doubled, assuming square openings of equal wire diameter effects ignored for this conceptual question.

Step-by-Step Solution:
Linear step = √2 between adjacent sizes.Area step = (√2)^2 = 2.Hence, area ratio ≈ 2.

Verification / Alternative check:
Tyler standard sieve scale lists sizes where mesh numbers increase by √2 in terms of opening changes, consistent with area doubling between steps.

Why Other Options Are Wrong:
1 or 1.5 do not match the geometric progression definition; "none" is unnecessary because 2 is the established value.

Common Pitfalls:
Confusing linear aperture ratio with area ratio; remember area scales with the square of linear dimension.

Final Answer:
2