In series circuit, Req = R₁ + R₂ + R₃ + ···
In parallel circuit, 
<h3>Q7.</h3>
total resistance in the upper branch = R₂ + R₃ = R₂ + 2


R₂ + 2 = 12
R₂ = 10Ω
<h3>Q8.</h3>


Req = 1.7Ω
I think it’s A.) it explains why the universe is made up of matter
Work done is equal to force by distance; so you take the force exerted, in newtons, and multiply that by the direction it's moved (from the starting point in a line, not along the path it's taken.)
<em>An is formed when an atom loses or gains one or more electrons. Because the number of electrons in an ion is different from the number of protons, an ion does have an overall electric charge. Consider how a positive ion can form from an atom. The left side of the illustration below represents a sodium (Na) atom</em>
The total momentum of the system is equal to 50 Kgm/s.
<u>Given the following data:</u>
To determine the total momentum of the system:
Mathematically, momentum is given by the formula;

<u>For Football player 1:</u>

Momentum 1 = 160 Kgm/s.
<u>For Football player 2:</u>

Momentum 1 = 210 Kgm/s.
Now, we can calculate the total momentum of the system:

Total momentum = 50 Kgm/s.
<u>Note:</u> We subtracted because the football players were moving in opposite directions.
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