http://hyperphysics.phy-astr.gsu.edu/hbase/torq2.html http://hyperphysics.phy-astr.gsu.edu/hbase/torq2.html http://hyperphysics.phy-astr.gsu.edu/hbase/torq2.html http://hyperphysics.phy-astr.gsu.edu/hbase/torq2.html