Answer:
The speed of water must be expelled at 6.06 m/s
Explanation:
Neglecting any drag effects of the surrounding water we can assume the linear momentum in this case is conserves, that is, the total initial momentum of the octopus and the water kept in it cavity should be equal to the total final linear momentum. That's known as conservation of momentum, mathematically expressed as:

with Pi the total initial momentum and Pf the final total momentum. The total momentum is the sum of the momentums of the individual objects, in our case the octopus and the mass of water that will be expelled:

with Po the momentum of the octopus and Pw the momentum of expelled water. Linear momentum is defined as mass times velocity:

Note that initially the octopus has the water in its cavity and both are at rest before it sees the predator so
:

We should find the final velocity of water if the final velocity of the octopus is 2.70 m/s, solving for
:


The minus sign indicates the velocity of the water is opposite the velocity of the octopus.
Answer:
Yes, because everything bounce off in every surface around any object.
Explanation:
Answer:
B
Explanation:
Protons have a positive electrical charge of +1,
Electrons have a negative charge of -1,
Neutrons have a neutral charge of about 0.
Answer:
The correct answer is option A, An antacid neutralizes excess hydrogen ions.
Explanation:
Antacid neutralizes the acid in the stomach. These are bases/ alkali's. The reaction between an acid and a base in known as neutralization thereby reducing burning sensations produced by the acid.
The antacid when reaches the stomach form gel like composition that lie on the top of food item in the stomach and prevent the oesophagus from the irritation caused by the acid.
Answer:
Explanation:
The calcite Crystal can be identified by carrying out an acid test on it. This is done by bringing it in contact with a weak acid which cause crack in it structure. Hence a little of carbondioxide gas is released.
Since diamond is the hardest object,it can be identified on a Mohs scale. Likewise it can be tested by bringing it in contact with a newspaper, if the letters on the paper are not seen, that shows it is a pure diamond.
Window glass is identified by the code on it.
While Quartz Crystal is identified by scratch test. When it is used to scratch all other softer stones and metal, it leaves mark on them.