<h2>Answer: protons and neutrons.
</h2>
The atomic nuclei of almost all elements consist of protons and neutrons.
The nucleus of an atom has very small dimensions. However, it <u>occupies its central part and concentrates more than 99% of its total mass.
</u>
It is in the nucleus that the protons (positive charge) and neutrons (neutral charge) are found.
Correct question is;
A thermal tap used in a certain apparatus consists of a silica rod which fits tightly inside an aluminium tube whose internal diameter is 8mm at 0°C.When the temperature is raised ,the fits is no longer exact. Calculate what change in temperature is necessary to produce a channel whose cross-sectional is equal to that of the tube of 1mm. (linear expansivity of silica = 8 × 10^(-6) /K and linear expansivity of aluminium = 26 × 10^(-6) /K).
Answer:
ΔT = 268.67K
Explanation:
We are given;
d1 = 8mm
d2 = 1mm
At standard temperature and pressure conditions, the temperature is 273K.
Thus; Initial temperature; T1 = 273K,
Using the combined gas law, we have;
P1×V1/T1 = P2×V2/T2
The pressure is constant and so P1 = P2. They will cancel out in the combined gas law to give:
V1/T1 = V2/T2
Now, volume of the tube is given by the formula;V = Area × height = Ah
Thus;
V1 = (πd1²/4)h
V2 = (π(d2)²/4)h
Thus;
(πd1²/4)h/T1 = (π(d2)²/4)h/T2
π, h and 4 will cancel out to give;
d1²/T1 = (d2)²/T2
T2 = ((d2)² × T1)/d1²
T2 = (1² × T1)/8²
T2 = 273/64
T2 = 4.23K
Therefore, Change in temperature is; ΔT = T2 - T1
ΔT = 273 - 4.23
ΔT = 268.67K
Thus, the temperature decreased to 268.67K
Lo experiences tidal heating primarily because lo’s elliptical orbit causes the tidal force on lo to vary as it orbits the Jupiter. Thus, lo’s elliptical orbit is essential to its tidal heating. This elliptical orbit, in turn, is an end result of the orbital resonance among lo, Europa and ganymade. This orbital resonance origin lo to have a more elliptical orbit than it would because lo intermittently passes Europa and ganymade in the same orbital position. We cannot perceive tidal forces of tidal heating in lo but rather we foresee that they must occur based on the orbital characteristic of the moons and active volcanoes on lo is the observational evidence that tidal heating is significant in lo.
Answer:
-6112.26 J
Explanation:
The initial kinetic energy, 
is given by
} where m is the mass of a body and 
is the initial velocity
The final kinetic energy, 
is given by
where 
is the final velocity
Change in kinetic energy, 
is given by
Since the skater finally comes to rest, the final velocity is zero. Substituting 0 for and 12.6 m/s for and 77 Kg for m we obtain
From work energy theorem, work done by a force is equal to the change in kinetic energy hence for this case work done equals <u>-6112.26 J</u>
Answer:
C. unlikely to combine with other elements.
Explanation:
In Chemistry, electrons can be defined as subatomic particles that are negatively charged and as such has a magnitude of -1.
Valence electrons can be defined as the number of electrons present in the outermost shell of an atom. Valence electrons are used to determine whether an atom or group of elements found in a periodic table can bond with others. Thus, this property is typically used to determine the chemical properties of elements.
Noble gases are chemical elements with eight valence electrons and as such have a full octet. Some examples are argon, neon, etc.
Hence, the full octet makes the gas (neon) unlikely to combine with other elements.
