Which one of the following is not the law of dry friction? a.If friction is neglected, the reactions are always normal to the surfaces on contact b.Friction always acts to oppose the relative motion of the free body c.If static friction is acting, the value of the friction force may vary from zero to its maximum value d.The force of friction is always normal to the surface e.All of the above

1 Answer

Answer :

d. The force of friction is always normal to the surface

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