1. What is RCF?

Relative Centrifugal Force (RCF), also known as g-force, is the measurement of the acceleration applied to a sample in a centrifuge. It represents the force relative to Earth's gravity and is crucial for standardizing centrifugation protocols across different equipment.

2. How Does the Calculator Work?

The calculator uses the RCF formula:

Where:

• \( RCF \) — Relative Centrifugal Force (×g)
• \( r \) — Radius in centimeters (distance from center of rotation to sample)
• \( RPM \) — Revolutions per minute
• \( 1.118 \times 10^{-5} \) — Conversion constant

Explanation: The formula converts rotational speed (RPM) to the actual gravitational force experienced by the sample, accounting for the centrifuge's radius.

3. Importance of RCF Calculation

Details: Accurate RCF calculation ensures reproducible results across different centrifuges, allows proper protocol standardization, and prevents sample damage from excessive g-forces.

4. Using the Calculator

Tips: Enter radius in centimeters (measure from center to sample position), and RPM value. Both values must be positive numbers for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: Why use RCF instead of RPM?
A: RCF provides standardized measurement across different centrifuges, while RPM alone doesn't account for rotor radius variations.

Q2: How do I measure the radius accurately?
A: Measure from the center of the centrifuge rotor to the bottom of the sample tube when positioned horizontally.

Q3: What are typical RCF values used in laboratories?
A: Common ranges: low speed (200-2,000 ×g), medium speed (2,000-20,000 ×g), high speed (20,000-80,000 ×g), ultracentrifuge (>80,000 ×g).

Q4: Can I convert RCF back to RPM?
A: Yes, using the formula: \( RPM = \sqrt{\frac{RCF}{1.118 \times 10^{-5} \times r}} \)

Q5: Why is the constant 1.118 × 10⁻⁵ used?
A: This constant incorporates unit conversions and gravitational acceleration to provide RCF in ×g units.