QUESTION 1: How does Brute Power Armor work? I will begin with a simpler question that I heard a lot around the release of Halo 3: ODST.
Throughout all of the Halo series, Brutes have been seen in a wide variety of armor.
On the whole, Brutes are killed the same way: shoot until their armor falls off and then aim for the head. The amount of shots required to take out the armor is dependent on the Brute and game. On other studies, the amount of damage it takes to achieve this is commonly represented by the variable "Pewpew", commonly measured in DMRs or even more commonly BRs.
Different armor, perhaps? Not at all, in fact. Similar to the Elites, the Brute Power armor remains the same (albeit more stylized in certain places than others) with varying degrees of strength.
How does this armor somehow gain more strength? As the picture warned, it is because of science. The Answer: Brute Armor is energized. 
As the illustration shows, Brute armor consists of two layers of ceramic armor with an energy current running through it. As the armor takes shots, the energy current dissipates impact and actually hardens the material further. With a higher current, this allows Brute Power Armor to potentially be more durable than any Energy Shielding.
For the more analogous of us, this can be represented by comparing Jiralhanae Power Armor to cake and Regenerating Shields to pie. While certain pies may be better than certain cakes, the best cake will always be better than the best pie, shown through this equation:
Pie = 3.1416 * 2.7182 = 8.5395
Cake = 7 +/- 2
If you were expecting a Portal joke, you should be ashamed of yourself.
Long story short, Brute Power Armor is more durable than Elite Energy Shielding. However...
If enough damage is done (or the energy current is disrupted), the super-hard ceramic breaks under the beating. Unlike Energy Shielding, the Power Armor falls apart and is busted.
Now, Mingy, you ask, Contact Harvest says that this armor is plasma powered, which fits with the theory,
but the Halo 2 and Halo: Reach Brutes do not have Power Armor. What gives?
The answer is that they do have Power Armor. However, much like the shields on a Stealth Elite, their armor is so pitifully charged that it is hardly noticeable.
So, Mingy, you ask again, since this topic would otherwise be over,
what determines the charge on Brute Armor? The answer, of course, is the beard.
Yes, the beard. However, it is not quantity of beard so much as quality. Allow the chart below to explain.
As you can see, there is a very particular beard length where the charge is optimal. While no beard at all presents a weaker armor, a long beard is also unacceptable. The Reach Chieftains even had to resort to using regenerating Energy shields to cover up their shame (and the Chieftain of Halo Wars just ignores bullets by being hardcore).
This also allowed the Elites to keep the Brutes well under control prior to Schism simply by enforcing a particular limit on facial hair.
However, the Prophet of Truth knew the secret of Jiralhanae technology. He ensured that his loyal Brutes were well outfitted. Tartarus' beard was so perfect, in fact, that it granted him near immunity even without wearing much physical armor.
Tragically, Sergeant Johnson knew of his weakness to Particle Beams, which were coincidentally used to power Jiralhanae barbershops prior to the Brutes' induction into the Covenant in 2492. Particle Beams coming into contact with his beard disrupted the shielding, the effect growing worse every three hits as the Particle Beams slowly trimmed Tartarus' beard.
Well, that's it for now. I hope this lesson was informative and entertaining. tune in next time for more "That's the Dumbest Shit I've Ever Heard" 
