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docs/reference/input/magnetic-force.md

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+# Magnetic Force
+
+Get the magnetic force (micro Teslas), in one of three specified dimensions.
+
+```sig
+input.magneticForce(Dimension.X);
+```
+
+### Parameters
+
+* dimension : [String](/microbit/reference/types/string) - one of three values specifying the axis of the force: ``x`` (left/right); ``y`` (forward/backwards); ``z`` (up/down); ``strength`` (the length of the vector)
+
+### Returns
+
+* [Number](/microbit/reference/types/number) - magnetic force, in micro-Teslas.
+
+### Example: metal detector
+
+The following example uses the `magnetic force` to control the brightness of the screen. When the magnetic force increases, the center LED will appear brighter.
+
+```blocks
+led.plot(2, 2)
+basic.forever(() => {
+    let f = input.magneticForce(Dimension.X)
+    led.setBrightness(f / 2000)
+})
+```
+
+### See also
+
+[compass heading](/microbit/input/compass-heading)
+