8.3: Absolute vs Relative References

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8.3 Absolute vs. Relative References

Relative reference (B3): shifts when the formula is copied. Move one row down, and B3 becomes B4.

Absolute reference ($B$3): locked. Copy the formula anywhere and it still points to B3.

The rule for parameter sweeps:

Constants use absolute references. The swept variable uses a relative reference.

In a tension vs. angle sweep, mass and gravity are constants in specific cells. The angle is the swept variable occupying a column. The correct formula placed in the tension column:

=($B$1*$B$2)/(2*SIN(RADIANS(A10)))

$B$1 and $B$2 are locked (constants). A10 is relative (shifts to A11, A12, etc. as the formula copies down). Copy this formula down 14 rows and you instantly have tension at 15 different angles.

⚠ Watch Out — Forgetting RADIANS()

SIN(30) does not compute sin(30°). It computes sin(30 radians) ≈ −0.988. The correct result for sin(30°) is 0.500.

The error produces no warning. The spreadsheet runs silently and produces a completely wrong answer. Always wrap trigonometric arguments: SIN(RADIANS(A10)), COS(RADIANS(A10)), TAN(RADIANS(A10)).

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8.3 Absolute vs. Relative References