Answer:
the human body isn't very efficient at converting food into useful work. The human body is less than 5% efficient most of the time. The rest of the energy is converted to heat, which may or may not be useful, depending on how cool or warm a person wants to be.
Explanation:
Answer:
B. By adding the number of protons and the number of neutrons
Explanation:
The atomic mass is determined by adding the number of protons and neutrons in an atom. An atom is made up of three fundamental particles: Electrons, Protons and Neutrons.
The protons and neutrons occupy a central region in an atom known as the nucleus. The nucleus is positively charged and mass concentrated.
If we compare the relative masses of the subatomic particles, the masses of protons and neutrons would be 1 and that of an electron would be 1/1840. This shows that the mass of electrons are negligible.
In order to ascertain atomic mass, we therefore add the number of protons and neutrons together. This is how we arrive at 12.011 as the value of the atomic mass of C and for other elements.
The atomic mass is also known as the mass number.
Answer: Condensation of moisture in the air onto the glasses.
Explanation:
When you come from a cold environment into a warm ski lodge, the glasses are at a much lower temperature than that of the lodge.
Because the air in the room contains moisture (water vapor), it condenses on a surface whose temperature is lower than the dew point of the room.
Answer:
4.5g/cm^3
Explanation:
Here, Mass(m)=67.5g
Volume(v)=15cm^3
Now, According to formula,
Density(p)=m/v
=67.5/15
=4.5g/cm^3
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.