Solar radiation is in9sj 7o cd.s7xncident on a planet, whose surface absorbs 65% of incident intensity. What is the albedo of thes7.7coxj s9d n planet?

  The orders of energy transformations in three power stations are zf9*obm 3uw (oax):idgiven;

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 e/ch/h0 7:.jb hpi;p:ckv h nlconstitutes a renewable and non-renewable source of en.pnjc/hivc7 h :behh;lk/ p0:ergy?

  Which of the following pairs constitutes a renewable and non-renewabl(zug-)h4xxe 4mkg rs,5*u yvn e source of ener*zyrmg5x ,4u e(vnkhgu -sx4)gy?

  Which of the following l1quc0 y/7 creis a non-renewable energy resource?

  Which of the following energy 9ws9o kqq.3+ocrgmn4 resources is non-renewable?

  The government of a medium sized city plans to replace coal power pl/6vmpih,x /u eer:3 vxants with photovoltaic cells to power t:/u me /xpexr63v,ivhhe 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 Neptune's orbit around the Sun is approximately 30 ti2w0c*nbggw. gmes the orbital radius g* 2bwgng cw0.of earth. Estimate the solar constant of Neptune.

  The following three statements give possible rexy-e.: * k0+zqcg)5izhtnnp n asons why the average intensity of sunlight incident on a solar panel during a dhxyk cn0:*t)ngzi. +ep5n- qz ay on earth is only 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 power stations. Examples of elemf 0agmwa: ; y4.wkqf/ctricity generation that botm aqwwyf :g; 0mk/.f4ah involve energy transfer from thermal to electrical are

  The albedo at the poles of Earth during a particular day is 0.8. What ,l 21 t/+ebw*pn xxkqcis the value of the absorbed intensityk xb2ct ,wx1+/pqne l* if the solar intensity is 700 $Wm^{−2}$?

  The sun radiates energy to tzae7f.ipes /, 3mar- uhe surface of the earth. Some of this energy is scatefs e7a,/3mzi .rpu a-tered and the 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, the s7zng +wled,b r r d,+y-hyxc;ov(n3:dolar 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 a specifixn (*5jq,jfmpe 6yoa8 c 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 + v/ufn,w) nz.znu7;* cdprbc 1psp5 ba 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.