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Second Force Calculator

Second Force Equation:

\[ F_2 = \sqrt{F_r^2 - F_1^2 - 2 \times F_r \times F_1 \times \cos(\theta)} \]

N
N
degrees

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1. What Is The Second Force Calculation?

The Second Force calculation determines the magnitude of an unknown force (F2) when you know the resultant force (Fr), another known force (F1), and the angle (θ) between them. This is based on the law of cosines applied to force vectors.

2. How Does The Calculator Work?

The calculator uses the force equation:

\[ F_2 = \sqrt{F_r^2 - F_1^2 - 2 \times F_r \times F_1 \times \cos(\theta)} \]

Where:

Explanation: This formula is derived from the vector addition of forces and the law of cosines, accounting for the angle between the two force vectors.

3. Importance Of Force Calculation

Details: Accurate force calculation is essential in physics, engineering, and mechanics for analyzing systems in equilibrium, designing structures, and solving force-related problems.

4. Using The Calculator

Tips: Enter all forces in Newtons (N) and the angle in degrees between 0-180. Ensure values are positive and physically meaningful for accurate results.

5. Frequently Asked Questions (FAQ)

Q1: What if the calculated F2 is negative?
A: Force magnitude should always be positive. A negative result indicates invalid input values or a mathematically impossible scenario.

Q2: Can this calculator handle forces in different units?
A: No, all forces must be in the same units (Newtons recommended). Convert all values to consistent units before calculation.

Q3: What angle range is valid?
A: The angle must be between 0-180 degrees. 0° means forces are parallel and same direction, 180° means opposite directions.

Q4: Does this work for 3D force systems?
A: No, this calculation is specifically for 2D coplanar force systems where all forces lie in the same plane.

Q5: What if I get an imaginary number result?
A: An imaginary result indicates the input values don't satisfy the vector triangle inequality, meaning the specified forces and angle cannot form a valid force triangle.

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