Answer:
A) Object A is 3.25 times hotter.
B) Object A radiates 111.6 times more energy per unit of area.
Explanation:
Wiens's law states that there is an inverse relationship between the wavelength in which there is a peak in the emission of a black body and its temperature, mathematically,
,
where
is the temperature in kelvins and,
is the wavelenght (in meters) where the emission is in its peak.
From here, if we solve Wien's law for the temperature we get
.
Now, we can easily compute the temperatures.
For object A:

.
For object B:


From this, we get that
,
which means that object A is 3.25 times hotter.
Stefan's Law states that a black body emits thermal radiation with power proportional to the fourth power of its temperature.
This is
,
where
is call the Stefan-Boltzmann constant.
From this, power can be easily compute:
,
and we can notice that
,
which means that object A radiates 111.6 time more energy per unit of area.
Answer: B) Methyl alcohol requires less than half as much energy per kg to evaporate than water does
Explanation:
Latent heat of vaporization is the amount of heat required to convert 1 kilo gram of liquid into its vapor state without change in its temperature.
Heat of vaporization is more for water than for methyl alcohol which means more heat is required to convert from liquid to vapour form.
As the Heat of vaporization for methyl alcohol (1100) is almost half as that of Heat of vaporization for water (2257) , it means Methyl alcohol requires less than half as much energy per kg to evaporate than water does.
Answer:
When you moved the compass near a bar magnet, the needle pointed toward the magnet's magnetic field and not toward the north.
Explanation:
Answer:
Physical quantities are the substances which can be measured. By measuring physical quantities, we can measure the mass, weight and other physical properties