Newton's Second Law of Motion states that "The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object." This Law describes the linear relationship between mass and acceleration when it comes to force and leads to the formula F = ma or force equals mass multiplied by rate of acceleration.

The work-energy theorem states that the work done by the sum of all forces acting on a particle equals the change in the kinetic energy of the particle. Simply put, work imparts kinetic energy to the matter upon which the work is being done.

f_Ad_A = f_Bd_B

For this problem, the equation becomes:

50 lbs. x 8 ft. = 90 lbs. x d_B

d_B = \( \frac{50 \times 8 ft⋅lb}{90 lbs.} \) = \( \frac{400 ft⋅lb}{90 lbs.} \) = 4.44 ft.

This problem describes an inclined plane and, for an inclined plane, the effort force multiplied by the effort distance equals the resistance force multipied by the resistance distance:

F_ed_e = F_rd_r

Plugging in the variables from this problem yields:

F_e x 11 ft. = 410 lbs. x 4 ft.
F_e = \( \frac{1640 ft⋅lb}{11 ft.} \) = 149.1 lbs.

A concentrated load acts on a relatively small area of a structure, a static uniformly distributed load doesn't create specific stress points or vary with time, a dynamic load varies with time or affects a structure that experiences a high degree of movement, an impact load is sudden and for a relatively short duration and a non-uniformly distributed load creates different stresses at different locations on a structure.