Letter B
without a medium, there is nothing to compress, hence, no wave. A fast- medium like a gas (air) is easy to compress and allows waves to move through it easily. a slow medium, like a liquid, is still pretty fast, but not as fast as air.
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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