Solar radiation is incident on a planet, whose surface abzhjfbg,jpg 7zit:3( 07 q;amlsorbs 65% of incident intensity. What is h7q ;ggz if3jp: (jamb0,t zl7the albedo of the planet?

  The orders of energy (,;x+l 6yj,wq oryevs transformations in three power 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 and non-renewable (f, ni .o0ndek+9 59 uzpzclkgi7joc( source of energy?gc7inpol(iz.n(z5+oj0 f,dke k9 c9u

  Which of the following pairs constitutes a renewable and non-renewabtx8viohxjs 7y-ht21:h/5g 7 qyovdv(le source of ene j8v:oiv-y1xts(o 7/thyghxv 2 qh5d 7rgy?

  Which of the following is d4fueat/ae9m 930pdky 8u0j qa non-renewable energy resource?

  Which of the following energy resources is non-renewe, gcwir0+6oe/ 3jlz jable?

  The government of a mediumlxai;w 1v)gf nb y+t.(+;dxtt sized city plans to replace coal power plants with photovlati); xn xf;g.t vb1w(+ +ydtoltaic 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 o )dt-iir: nyg/f Neptune's orbit around the Sun is approximately 30 times the orbital radius of earth. Estimate the solar constant of Neptundg-/)r:iy nt ie.

  The following three statements give posso472 xi et6sbpible reasons why the average intensity of sunlight incident on a solar panel during a day on earth is on4x bs2it7epo6ly a fraction of the solar constant.
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 pow ube ;rrteq1z6 *x mk:r6hcw(5er stations. Examples of electricity generation that both involve energu6 q5*:c (xeb1m ;trrwh ek6zry transfer from thermal to electrical are

  The albedo at the poles of Earth dq;*gow.z39 sei t54z5y ;o+rl,e9wc j wnlev guring a particular day is 0.8. What is the value of the absorbed intensity if the solar intensit;;4 y5.5lzvi cr+ w3nseegqew, *ootl w99jgzy is 700 $Wm^{−2}$?

  The sun radiates energy to the surface of the earvgry23y7s2 /ia b gp,nth. Some of this energy is scattered and bysnyg,3 / 7ap v2rgi2the rest reaches 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, th3oz6yt5lw ay( e solar intensity on the Earth's surface is 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 fuel with wjr4k6:ygec:, t(cd 7qxk(lza 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 of a bok (7 sv/emsu)9w4 bcrqdy
(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.