Solar radiation is incident on a m9gc13;(zjo s /wbfhj planet, whose surface absorbs 65% of incident intensity. What is the albedo of the planeto9 /wj 3jbgs1fmch(;z?

  The orders of energyu4*q0izsy6 x8w9x nxfgok p:6 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 constinrj49/ eardaz.* b-fjpjp-q4tutes a renewable and non-renewable source of energy bad/4pp9*nj.4reqf-z j j-a r?

  Which of the following pairs constitujz99v70m(:xmxj0zp mx-s6 uwn. d n eites a renewable and non-renewable source of energy?j.z(0mu7 zxsd6wm 0pn jxi- xm9vn9 :e

  Which of the following is a non-renewable energy rgi(bjvkqj 7l:6;f) m; gsaup -esource?

  Which of the following energy resources :z(1y:pbyw c glk pxl)i-g66 g4p-hkkis non-renewable?

  The government of a medium sized cn,qyd/-tv9* z-sal zj+ j( 8cb ls*qwmity plans to replace coal power plants with photovoltaic cells to power alwyjqv/q 8(* c, *d+9tbn l-mjzs-szthe 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-//u5k-bkyg g f.db 8oj7b ,)o e5kxeajp:s st the Sun is approximately 30 times the orbital radius of earth. Estimate the solar constant of Neptbyb ),u g 5d7k-gsjo/ fp.-e/jkex tos:bak 85une.

  The following three statem dtdo90*v.x:*icf3 ay sn7 wgpents give possible reasons why the average intensity of.3tfa7dcydp** o nv9 sg:ix0 w sunlight incident on a solar panel 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 o6slveh i -3wl)s,t0*q8v rc jlccur in power stations. Examples of electricity generation that both involve energy tran hqv)wivsec3-j rsltl8* ,l0 6sfer from thermal to electrical are

  The albedo at the poles of Earth during a particular day is 0.8. What is tht/.4wr xyg1 j 1ow-rpm:1 g ifto8kzb2e value of the absorbed intensity if the solar intens 48rz.owp:- rb11f/gt wxiy 1jgkm2toity is 700 $Wm^{−2}$?

  The sun radiates energy to the surface of the earth. Some of this enercz 66,5pakcuv.gos ( pgy is scattered and the rest reaches.zo65kp 6u ,gp(c vcas 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 su /cx yg65vrrw-rface 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 sp l6lmg6f+sg0/,r mf qkecific 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 albe2irm)9 f+xxty +y;kycdo of 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.