Explanation: The work is defined as the dot product of the force and the distance. This means that the work done does depends upon the angle of the force. That is the angle which is being made by the force vector to the surface of action of the force.

Explanation: The net forces acting on the body is shown with the help of the resultant forces. There are two types, first the frictional and the second is normal. This is because the resultant forces have the sum of all the forces which are acting in the direction which is same.

Explanation: As 3D is defined as the three axis system, we have to consider the equilibrium in all the three axis. This will make the equilibrium go on all the axis of the 3D space. And hence will cancel all the forces.

Explanation: The answer is false as the equations asked are scalars. As we make the net sum of the forces along the axis equal to zero. Of course this equation comes from the solving the vector forms, but still the result is a scalar, hence the equations are scalar.

Explanation: The net forces acting on the body is shown with the help of the resultant forces. There are two types, first the frictional and the second is normal. This is because the resultant forces have the sum of all the forces which are acting in the direction which is same.

Explanation: The work is defined as the dot product of the force and the distance. This means that the work done does depends upon the angle of the force. That is the angle which is being made by the force vector to the surface of action of the force.

Explanation: The development of the couple moment is when there is prevention of the rotation of the attached member. This is the basic condition for the equilibrium of the couple moments in any dimension. This rule is applied when the couple moments are taken into the account for the equilibrium of the body.

Explanation: The work done by the couple is defined as the product of the moment and the del angle. This means that the work done does depends upon the angle of the moment. That is the angle which is being made by the moment vector to the surface of action of the moment.

Explanation: For the equilibrium in the three dimensional system of axis we have all the conditions true as, ∑Fx=0, ∑Fy=0 and ∑Fz=0. Also, we have the summation of the forces equal to zero. Which is not a non-zero value.

Explanation: The work is defined as the dot product of the δ force and the δ distance. This means that the work done does depends upon the angle of the force. That is the angle which is being made by the force vector to the surface of action of the force.

Explanation: The work done by the couple is defined as the product of the δ moment and the δ angle. This means that the work done does depends upon the angle of the moment. That is the angle which is being made by the moment vector to the surface of action of the moment.

Explanation: The virtual work done is working on the equation: δU = 0. This means that the body must be in the equilibrium and the network done must be zero. Thus the unknown forces are being determined by the same technique.

Explanation: The answer is obviously yes. If we are having any difficulty in making the vector components, then we can go to 2D. As if the particle is in equilibrium, the net force will be zero. No matter where you see first. Network done is zero.

Explanation: The negative sign implies things are in the opposite manner. If the force is coming negative this doesn’t mean that it is impossible. But it means that the force is in the opposite direction w.r.t the direction set by you in the free body diagram.