Look at this fill how you should move the bow perpendicular across the strings
The bow position is dependent on how load you are playing.
If you are playing loud you should move the bow closer to the bridge. If you are playing softly you should move closer to the finger board.
As mentioned it is not good to put force on the violin. Make sure that you are relaxed when playing.
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The famous German mathematician Helmholtz explained how the violin is working Get the explanation here.