Solar radiation is incident on a planet, whose surface abszst dzb kg vlok ;lv5::wdx0+ga k;9:2orbs 65% of incident intensity. What is the ask :vblkt;5 ;20go vg:dw :zxa9+lkdz lbedo of the planet?

  The orders of energy tran w-2ssly+vom hr1k9 o7sformations 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 renewab26ws kq/ghq6vp()x xjle and non-renewable source of energpgk( x)shvq/ j 62q6xwy?

  Which of the following ix 2l(fkm+, mvekitkyl:d 3w;+; 8nrapairs constitutes a renewable and non-renewable source of en;ayvkk8(+ fl,r+3e 2kli:m mwdtx;n iergy?

  Which of the following is a non-renewable enerap wv)om8gmo /s +f:u7ew a)ow+ 2gj5o(xka 0ygy resource?

  Which of the following energy resources is non-renewab* *tup2x qh nu*hy3bobd2*5 qwle?

  The government of a medium sized city plans to replace coal powe 8os);n76 .4nd/b8ym h rjnfp u9u*jbx -vkpgsr plants with photovoltaic cx6 y o)vsb7s/ 8kbp -u.d84h;r gn9 jufp*njmnells 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 approximawsw1;5n ;wzo(u lj/l ately 30 times the orbital radius of earth. Estimatew 5 1(n;aswlljz ;/owu the solar constant of Neptune.

  The following three statements giv-utjd*z06ay 6gz0c pvcq bo+5e possible reasons why the average intensity of sunlight incident on a solar panel during a day on +uzgobpv6d0 tzc*qcy60-a 5 jearth 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 v*pzct.b rk w3j(+ein3r /io8occur in power stations. Examples of electricity generation that both involve en3toc ibipnre/+ jz8r3w .*v(k ergy transfer from thermal to electrical are

  The albedo at the poles of Earth durx 0l/gcgp+-zh z-kr, king a particular day is 0.8. What is the value of the absorbed intensity if the solar intensityl,kh+zp/g xkr-c z0-g is 700 $Wm^{−2}$?

  The sun radiates energy to the surface of the a vj)+yt ,i,((usb.wf hf2uyfearth. Some of this energy is scattered and the rest reaches thb+ 2f) s a.,((uv,ut hwyfjfiye 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 c71egidl e: (u))ogiosolar 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 uv,a5 z ,n pikl*h:zh;k ker75with 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 of a)yst kn)6)u.em 7xm4 u8imkek 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.