Answer:
A. 1.64 J
Explanation:
First of all, we need to find how many moles correspond to 1.4 mg of mercury. We have:
where
n is the number of moles
m = 1.4 mg = 0.0014 g is the mass of mercury
Mm = 200.6 g/mol is the molar mass of mercury
Substituting, we find
Now we have to find the number of atoms contained in this sample of mercury, which is given by:
where
n is the number of moles
is the Avogadro number
Substituting,
atoms
The energy emitted by each atom (the energy of one photon) is
where
h is the Planck constant
c is the speed of light
is the wavelength
Substituting,
And so, the total energy emitted by the sample is
70-10/70 x 100 percentage change ....
60/70, 6/7 fract change
Tension is the force causing the path. It is always directed inward for circular motion. To hit the ceiling you need B. The stopper will travel along the tangent line it was moving when released (when tension goes to 0). This is upward in B so it will keep going up to the ceiling.
The velocity is pointed along the tangent line at all times (parallel to the edge of the circle at any point)
Answer:54 kj
Explanation:P1 = P2 = 1000 kPa
1Q2 = 84 kJ
1W2 = P1 (V2 – V1)
= 1000 (0.06 – 0.03) = 30 kJ
1Q2 = 1W2 + 1U2
U2 – U1= 1Q2 – 1W2 = 84 – 30 = 54 kJ
Answer:
That is a very broad question. One thing that does not seem to be considered is the depletion of the ozone layer at high altitudes.
In the 1960's chlorofluorcarbons (CFC,s) became popular as refrigerants, spray can propellants, etc. In January 1989 the Montreal Protocol was passed which has greatly reduced the use of these substances. However, it may be several decades before the ozone layer can be replaced and again absorb harmful ulraviolet rays that may be partly responsible for the increase in global warming.
(One chlorine atom at high altitudes can be responsible for the destruction of 100,000 molecules of ozone - catalytic reaction)
