true and false questions
a. Any force F acting on a rigid body can be moved to anarbitrary point O provided that a couple is added whose moment isequal to the moment of F about point O.
b. The cross product obeys the commutative law, i.e. A x B = B xA
c. The centroid and center of mass of an object will coincide ifwe assume that the object is of non-uniform density.
d. In a truss problem that involves a large number of joints, ifone is interested to nd the force in only a few members, then themethod of joints is a faster approach than the method ofsections.
e. In problems that involve shear and bending moment diagrams,if there are no couples applied at the ends of the beam, and ifthere are no supports imposing moment reactions at the ends, thenthe bending moment diagram always starts and ends at zero value forthe beam's ends.
