Solar radiation is incident on a planet, whose surface ax d h/1anfaxvu)(:8ly1o;j ix bsorbs 65% of incident intja lx a(uo8xv/ifx11dn :hy ;)ensity. What is the albedo of the planet?

  The orders of energy transformations in three pow nzi;z5 xy;+gder stations are given;

I. chemical → thermal → kinetic → electrical
II. kinetic → kinetic → electrical
III. gravitational potential → kinetic → electrical
Which row correctly matches the type of power station with the energy transformations?

  Which of the following pairs constitutes a renewable 6fv m,pxywl7b tu59t2j - j.qoand non-renewable source of energy?y ,.j527j- bftwq6polx tvum9

  Which of the following pairs constitutes a renewable and non-renewable f*4vbx+l vwm0source of energy?vbf* 4vm +w0lx

  Which of the following is a non-renewable energy resource*cs* 8)nykusm*9so + n v9hplty8tff2?

  Which of the following energy resources is non-renewaga1 ja87bzik,xm7 ; okble?

  The government of a medium sized city plans to replace coal power plann i-6nlpn43ef ts with photov4 en l6fin-p3noltaic cells to power the city.
The following data are available:
Total area available for photovoltaic cells = 62.6$km^2$
Maximum intensity of light incident on photovoltaic cells = $1.36\times10^3$ $Wm^{−2}$
Average efficiency of energy conversion in photovoltaic cells = 20 %
Hours of sunshine in one month = 150 hours
1.Explain why the government's choice to reduce its reliance on coal would be beneficial to the Earth's climate.
2.Outline, in terms of energy changes, how electrical energy is generated from coal.
3.Using the data given, calculate in $GJ$ the maximum expected energy generation for one month. $Electrical energy obtained$ =    $\times10^6\,GJ$

  The average radius of Neptunewawlw1z0+ 2 9hb as-*qhoi7dy 's orbit around the Sun is approximately 30 times the orbitz*+sl d-1qaih7 b92w0aywho wal radius of earth. Estimate the solar constant of Neptune.

  The following three statements give possible reas3nira v7ke /kll3/v 1 c)0uhi* ge,evvons why the average intensity of sunlight incident on a solar panel during a day on earth is only a fraction of the solar constani/37u)k0lge ec1 nvi,l ev*rvh k/3v at.
I. Scattering of sunlight in the atmosphere
II. Rotation of the earth
III. The surface of the solar panel is not perpendicular to incident of sunlight
Which of the statements are correct?

  Several energy conversions occur in power stations: / ky 7npsu/k7em/iio. Examples of electricity generation that boimo/ny:u is/ e7k /pk7th involve energy transfer from thermal to electrical are

  The albedo at the poles of Earth during a particular day is 0.8. What is the v8grxjlkwx+n-tf2td7a9 62e c q9 *vqdalue of the absorbed intensity if th6qdqk-2xc2v lg 7 ra tj+*exd9 8fwnt9e solar intensity is 700 $Wm^{−2}$?

  The sun radiates energy to the surfac 2( lrln qo:n 2ww,tw(kkc,6zwdqz +n9e of the earth. Some of this energy is scattered and the rest reache (9rn nozw2zqw:c,,2llt (n kw w6d+qks the earth's surface.



1.Differentiate between heat transfer methods: conduction, convection and thermal radiation.
2.At any given time, the power of the radiation of the sun absorbed by the earth's surface is $P$.
$P$is given by
$P\,=\,(1−α)SπR^2$
Where $α$ is the albedo of the earth’s surface.
(1)Show that the average intensity of radiation $I_{avg}$​ that is absorbed by the earth's surface is given by $I_{avg}$​=$\frac{(1−α)S}{4}$. ​
(2)Calculate the average intensity of the radiation that is absorbed by the earth's surface. The earth's albedo is 0.3. $I_{avg}$ =    $Wm^{-2}$
Some of the infrared radiation from the earth is absorbed and reradiated by the greenhouse gasses.
3.Explain this absorption and emission of radiation in terms of molecular energy levels.

  On a certain day, the solar intensity on the Earth's surface i 16+onh ada2 :op uqacxug,)k*s 300 $Wm^{−2}$. Photovoltaic cells which have an efficiency of 20% are used to convert solar energy to electrical energy. What should be the minimum area of the photovoltaic cells to produce an output of 6.0 kW assuming that the incident light is normal to the surface of the panel?

  A natural gas plant burns fueltia923zm0xwru77h z x with a specific energy of 80$MJkg^{−1}$.
The rate of energy input of the natural gas is 1.6$GW$. What is the rate at which the fuel burns?

  1.(1)Define the albedo o -i5ysf48qeg 0j-lxdw f a body
(2)It was suggested that painting rocky mountain tops with a white chalk-based paint could help reduce the impact of global warming. In terms of albedo, explain why this could work.
2.(1)Given that the radius of the earth is $6.4\times10^6\,m$, show that at any given time, the total amount of energy incident on the earth's surface is approximately $1.8\times10^{17}\,J$ per second. P =    $\times10^{17}\,W$
(2)The average albedo of the Earth is 0.30. What is the rate at which the Earth absorbs energy from the sun?
(3)Using your answer from (b)(ii) and ignoring atmospheric effects, estimate the average temperature of the earth for which equilibrium would be established. Assume the earth's average emissivity is 0.80.T =    K
(4)Greenhouse gases in the atmosphere elevate the average temperature of the earth such that it is higher than the answer found in (b)(iii). Explain the mechanism by which this occurs.