Increasing Friction, brakes slowing down a bike, wearing spiked shoes on ice, a car going round a corner, tying a knot, rubbing our hands in cold weather, Decreasing Friction, a snowboarder going fast downhill, adding grease to a bike chain, a fish swimming, using wheels on a suitcase.

لوحة الصدارة

النمط البصري

الخيارات

تبديل القالب

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