Gears - The PjProblemStrings.
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Gears - The PjProblemStrings Gears are simple machines. They are used to change the direction of motion; decrease or increase the speed of motion; and magnify or reduce applied force.

(a) Figure 133.1(a) is an illustration of an eggbeater. Gears A, B and C enable the eggbeater to do its work. Physicists say, the gear is a type of a lever. Classify the eggbeater as a lever.
(b) Give a range for the theoretical mechanical advantage of the eggbeater of 133.1(a).
(c) Explain how the gears of the eggbeater change the speed of motion.
(d) Figure 133.1(b) is a rack-and-pinion arrangement of gears. What is its usefulness.
(e) Imagine a gear train consisting of four gears: A (10 teeth), B (40 teeth) C (20 teeth) and D (10 teeth). A in mesh with B, C is rigidly fixed on the same shaft as B; C in mesh with D. What is the overall speed ratio of the gear train?
(f) What is an idler gear?
(g) Write the PjProblemStrings at play with respect to figures 133.1(a) and 133.1(b).

The strings: S7P3A32 (Force-Push).

The math:
Pj Problem of Interest is of type force (push). (a) The eggbeater is a third class lever. Effort is between resistance and fulcrum and effort applied is greater than resistance inorder to increase speed.

(b) Theoretical Mechanical Advantage (T.M.A) for third class levers is a fraction. So, 0 < T.M.A <1.

(c) Gear A has 32 teeth; gear B has 8 teeth and gear C has 8 teeth.
So, there are four complete revolutions of B to one revolution of A.
So, C also revolves four times since it has the same number of teeth with B.

(d) A pinion is the smaller of two gears meshed together. In other words, of the two gears, the pinion has fewer teeth. A rack-and-pinion gear arrangement is used to change rotary motion to linear motion.

(e) Consider figure 133.2. Four complete revolutions of A in one complete revolution of B (as a result of respective gear teeth).
B and C fixed to same shaft, so one complete revolution of C in one complete revolution of B.
Two complete revolution of D in one complete revolution of C (as a result of respective gear teeth).
So, overall speed reduction is 1/2.
In general, gear speed formula is as follows:
S2 = S1(T1/T2).
Where
S1 = speed of first shaft in train
S2 = speed of last shaft in train
T1 = product of teeth on all drivers
T2 = product of teeth on all driven gears

(f) Two external gears that are meshed rotate in opposite directions. An idler is a third gear placed between the two gears to make them rotate in the same direction (figure 133.3). The idler does not change the gear ratio in speed calculation. (d) 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.
Eggbeater (figure 133.1(a)
Forces at play of type push. PjProblemStrings S7P3A32
Motions at play, rotational at effort and resistance, PjProblemStrings S7P4A42
Rack-and-Pinion (figure 133.1(b)
Forces at play of type push. PjProblemStrings S7P3A32
Motion at pinion, rotational, PjProblemStrings S7P4A42
Motion at rack, linear, PjProblemStrings S7P4A41

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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