Intersect
Extract curves resulting from the intersection of the sketch plane with selected parts.
Create Intersection Curves
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On the Sketch ribbon, select the Intersect tool.
- Select the parts, solids, surfaces, or elements to be intersected.
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Click Plane on the guide bar then
select the sketch plane with which to intersect.
Figure 1. Select solid and intersection plane 
Once the plane is accepted, the intersection curves are shown as a dotted red line or curve.Figure 2. 
- Right-click and mouse through the check mark to exit, or double-right-click.
Tip:
- The origin of the plane becomes the origin of the sketch. Once the sketch is created, additional parts, solids, or surfaces can be selected. The plane definition is locked for that particular sketch.
- To convert an intersection line to a sketch curve, right-click the intersection line and select Create Curve.