Answer:
f>1000Hz and wavelength=0.343 m
Explanation:
We are given that
Frequency of stationary siren,f=1000 Hz
Wavelength of stationary sound,
When a observer is moving towards the siren then the frequency increases.
Therefore,an observer who is moving towards the siren measure a frequency >1000 Hz.
The wavelength depends upon the speed of source.
But we are given that siren is stationary.
Therefore, source is not moving and then the wavelength remains same.
f>1000Hz and wavelength=0.343 m
<span>The unknown substance is silver.
I don't see a list of available substances, but let's see if there's something reasonable available that will match. First, let's calculate the density of the unknown substance. Density is mass per volume, so
273 g / 26 mL = 10.5 g/mL
Looking up a list of elements sorted by density, I see the following:
10.07 Actinium
10.22 Molybdenum
10.5 Silver
11.35 Lead
And silver at 10.5 g/ml is a very nice match for the unknown substances' density of 10.5 g/ml.</span>
Answer:
As the concentration of a solute in a solution increases, the freezing point of the solution <u><em>decrease </em></u>and the vapor pressure of the solution <em><u>decrease </u></em>.
Explanation:
Depression in freezing point :
where,
=depression in freezing point =
= freezing point constant
m = molality ( moles per kg of solvent) of the solution
As we can see that from the formula that higher the molality of the solution is directly proportionate to the depression in freezing point which means that:
- If molality of the solution in high the depression in freezing point of the solution will be more.
- If molality of the solution in low the depression in freezing point of teh solution will be lower .
Relative lowering in vapor pressure of the solution is given by :
= Vapor pressure of pure solvent
= Vapor pressure of solution
= Mole fraction of solute
Vapor pressure of the solution is inversely proportional to the mole fraction of solute.
- Higher the concentration of solute more will the be solute's mole fraction and decrease in vapor pressure of the solution will be observed.
- lower the concentration of solute more will the be solute's mole fraction and increase in vapor pressure of the solution will be observed.
The first blank: HEAT
The second blank: ELECTRICAL
