Solar radiation is incidentxvv54gpsf 2s) sl 1rw0coiw67h5pp (f on a planet, whose surface absorbs 65% of incident intensity. What is the albedo of th (270 5ss14ppvi oxgw vl ff)cwr56shpe planet?

  The orders of energy transformations in three power stations are gi dpkex1u/7)jfi j() tfven;

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 constitute8wnn q3lr7lse+4 lkd2s a renewable and non-renewable source of energy4nnler23lwkdlq s7+8?

  Which of the following pairs constitutes a renewaxr d75nfw4)pjzyar n z91n4z,ble and non-renewable source of energyr4 ,zjp7nzx5wf 9z)4ny a 1rnd?

  Which of the following is a non-renewable 33 s/xcm x fb64cw1jmdenergy resource?

  Which of the following energy resources is53h ztuih62,(o tm ypwi* r7gz non-renewable?

  The government of a medium sizep kg/7:,h)s t so99bsixfdz.rz5zjs nug 1f+0d city plans to replace coal power plants with photovol)x1f7knszb z+sizpt.59d/s u rgoh fjsg ,0:9taic 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 Neptune's orbit around the Sun is approximately 3(zbp veyf17sg.m 32h qhh7tp; 0 times the orbital radius7(phpzfhq ;b.mvy71g s 2the3 of earth. Estimate the solar constant of Neptune.

  The following three statements give possible reasons why the average inte+ zcd67muke*y nsity of sunlight incident on a solar pc7yu6z d *+kemanel during a day 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 statio0 om*isyop,wn: nt9z /ns. Examples of electricity generation that both involve energy toz09,siyn p/o*mnt:w ransfer from thermal to electrical are

  The albedo at the poles of Ear/w)m9bzb+ iosji .oo0th during a particular day is 0.8. What is the value of the a9oo)+o m bs.jib0 iw/zbsorbed intensity if the solar intensity is 700 $Wm^{−2}$?

  The sun radiates energy to the surface 8l :;jk+k/ rb+u auvmynqo :f7of the earth. Some of this energy is scattered and the rest reaches ymv8+oa7lbunfu+ : kq/:jk;r 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( + q(ya,/y hr3++3ef limque5:v2wigtwipkis 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 specificrt2 lh:. df)bj 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 a6jdw fqhp3:vip:7 x-bn5 8nfy 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.