Explanation:
<u>(a)</u>
<u>The measure of material's ability to conduct thermal energy (heat) is known as thermal conductivity.</u> For examples, metals have high thermal conductivity, it means that they are very efficient at conducting heat.<u> The SI unit of heat capacity is W/m.K.</u>
The expression for thermal conductivity is:
Where,
q is the heat flux
is the thermal conductivity
is the temperature gradient.
<u>(b)</u>
<u>Heat capacity for a substance is defined as the ratio of the amount of energy required to change the temperature of the substance and the magnitude of temperature change. The SI unit of heat capacity is J/K.</u>
The expression for Heat capacity is:
Where,
C is the Heat capacity
E is the energy absorbed/released
is the change in temperature
<u>(c)</u>
<u>Thermal diffusivity is defined as the thermal conductivity divided by specific heat capacity at constant pressure and its density. The Si unit of thermal diffusivity is m²/s.</u>
The expression for thermal diffusivity is:
Where,
is thermal diffusivity
is the thermal conductivity
is specific heat capacity at constant pressure
is density
Answer:
a) 2622.903 N/m^3
b) 1.38233
c)4.878811765
Explanation:
Find the void ratio using the formula:
Here;
is specific gravity of soil solids
is unit weight of water = 998 kg/m^3
is the moisture content = 0.17
is the void ratio
is the unit weight of soil = 14.9KN/m^3
Saturation Ratio Formula:
S is saturation rate
Substitute Eq 2 into Eq 1
Specific gravity of soil solids
Saturated Unit Weight
Answer:
c) 1.75 g/cm³
Explanation:
Given that
Radii of the A ion, r(c) = 0.137 nm
Radii of the X ion, r(a) = 0.241 nm
Atomic weight of the A ion, A(c) = 22.7 g/mol
Atomic weight of the X ion, A(a) = 91.4 g/mol
Avogadro's number, N = 6.02*10^23 per mol
Solution is attached below
Answer:
C
Explanation:
One of the disadvantages of solar cells is that electricity storage systems are not readily available. Excess energy generated by the solar panels are wasted except they are stored by solar batteries for later use. There are various systems for storing electricity from solar cells apart from solar batteries which is the common storage system. An example of another electricity storage system for solar cell is using the water electrolyzer to store solar energy which can be used to later generate hydroelectricity.
Advantages of a solar cell includes Renewable energy, Economy-friendly and environmental-friendly energy and good durability
The maintenance is in charge of controlling that all the machines of a company are constantly running in order to avoid damages that cause loss of money when the machines fail.
The maintenance based on vibration monitoring allows to predict failures in some rotating machines such as:
1. worn bearings
2.alignment
3.balance
4. affected gears
5. bent shafts
6. rocks
7.gags
8. eccentricity
9. failures of electrical origin
