Block And Tackle - The PjProblemStrings.
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Block And Tackle - The PjProblemStrings Figure 130.1 is a basic combination of a type of simple machines.

(a) What type of simple machine is illustrated in figure 130.1?
(b) What is the theoretical mechanical advantage of the machine illustrated in figure 130.1
(c) Write the PjProblemStrings at play with respect to figure 130.1?

The strings: S7P3A31 (Force-Pull).

The math:
Pj Problem of Interest is of type force (pull). (a) The machine illustrated in figure 130.1 is a luff upon luff which is a basic combination of blocks and tackle (pulleys).
Pulleys are either fixed or movable. Fixed pulleys help change direction of effort while movable pulley help multiply the effort.

(b) The theoretical mechanical advantage (T.M.A) ignores the effect of friction. TMA = distance effort moves/distance resistance moves = Resistance/effort.
So, for the machine in figure 130.1:
1200 lbs load is supported by three falls running from block A.
So, each part supports 1/3 of the load = 400 lbs
Block B which has a 400 lb pull on it is supported by four falls
So, each part supports 1/4 of the load = 100 lbs
So, mechanical advantage = 1200/100 = 12.
That is a 100 lb pull applied to the luff and luff hauled a 1200 lb load.

(c) Assuming a multi-matter-multi-dynamic space (S7) because of the dynamism of atoms of materials and the fact that there are several matter in the space.
Forces at play of type pull. PjProblemStrings S7P3A31
Motion at play, linear. PjProblemStrings S7P4A41
static equilibrium at fixed pulley. PjProblemStrings S7P7A71
Dynamic equilibrium at movable pulley. PjProblemStrings S7P7A72

Math The Universe is composed of matter and radiant energy. Matter is any kind of mass-energy that moves with velocities less than the velocity of light. Radiant energy is any kind of mass-energy that moves with the velocity of light.
Periodic Table
Composition And Structure Of Matter
How Matter Gets Composed
How Matter Gets Composed (2)
Molecular Structure Of Matter
Molecular Shapes: Bond Length, Bond Angle
Molecular Shapes: Valence Shell Electron Pair Repulsion
Molecular Shapes: Orbital Hybridization
Molecular Shapes: Sigma Bonds Pi Bonds
Molecular Shapes: Non ABn Molecules
Molecular Orbital Theory
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