Physics 1009 Final Exam Questions With Detailed Correct Answers Solution Guaranteed

Main chemical elements that compose Earth's atmosphere - correct answers Nitrogen Oxygen Argon Carbon dioxide Nitrogen percentage in Earth's atmosphere - correct answers 78.08% Oxygen percentage in Earth's atmosphere - correct answers 20.95% Argon percentage in Earth's atmosphere - correct answers 0.93% Carbon dioxide percentage in Earth's atmosphere - correct answers 0.038% Four main layers of Earth's atmosphere - correct answers Troposphere Stratosphere Mesosphere Thermosphere Troposphere - correct answers -layer closest to earth -weather layer Troposphere temperature - correct answers -temperature decreases with altitude -heating from below -hot air rises -geothermal heating -churning air masses inside troposphere which gives rise to air circulation Stratosphere - correct answers -home of the ozone layer -O3 absorbs solar UV radiation Stratosphere temperature - correct answers -temperature increases with altitude -hot air rises (continues to rise) -heating from above -cooler chunks of air sink down which causes air layers to be stratified (opposite of troposphere) Mesosphere - correct answers middle layer Mesosphere temperature - correct answers -temperature decreases with altitude -heating from below Thermosphere - correct answers -outermost layer -gases escape into space Thermosphere temperature - correct answers -temperature increases with altitude -gases are heated from above (solar radiation) Greenhouse effect - correct answers the capture of energy by gases in the atmosphere Greenhouse gas process - correct answers -earth absorbs solar radiation -earth sheds energy by emitting infrared light (heat) -heat becomes trapped in the atmosphere (insulated heat) What is going on at a molecular level when greenhouse gases trap heat in the atmosphere? - correct answers -Greenhouse gases (CO2, Water Vapor, Methane) -Non greenhouse gases (Nitrogen, Oxygen, Argon) (do not trap infrared light) -Vibration and resonance -Greenhouse gases have more structure, more geometry -Non greenhouse gases are symmetrical, no entry way for energy to get in and redirected Climate - correct answers long term trends in temperature and precipitation Weather - correct answers short term variation in temperature and precipitation First Milankovitch cycle - correct answers -earth's orbit is elliptical rather than circular -orbital path stretches/ shrinks overtime -eccentricity (super stretched) of orbit increases and decreases over a 100,000 year cycle -gravitational pull causes this -does not affect the overall sunlight absorbed What is it called when we are closest to the sun, when does this occur? - correct answers perihelion, January What is it called when we are farthest from the sun, when does this occur? - correct answers aphelion, July Second Milankovitch cycle - correct answers -earth's axis is tilted with respect to our orbital plane (shifts in earth's obliquity) -axial tilt ranges from 22.1 degrees to 24.5 degrees over a 40,000 year cycle -affects the season variation Third Milankovitch cycle - correct answers -north pole traces out a giant circle in space -axial precession occurs every 26,000 years -changes the timing of the seasons on the basis of aphelion and perihelion -eccentric strong and weak seasons due to direct and indirect sunlight (with first cycle) Proxy data - correct answers information recorded and preserved in natural features of the environment Ice core samples - correct answers -yearly snow layers trap and preserve pockets of air -tell us historical carbon dioxide concentration and historical global temperatures -most of earths oxygen is oxygen 16 -oxygen 18 is heavier, harder to evaporate, condenses quicker -ice cores that have more precipitation, have more oxygen tell us that the temperature was warmer due to more evaporation -ice cores that have less precipitation, have less oxygen, which means temperature was colder Natural influences on climate - correct answers -cycles in sun's intensity -volcanic eruptions -el nino/ la nina cycles Key indicators for anthropogenic climate change - correct answers -atmospheric indicators -oceanic indicators Atmospheric indicators - correct answers -increasing concentrations of greenhouse gases -increasing global average temperature Oceanic indicators - correct answers -rising sea levels due to thermal expansion (freezing and heating) and glacial melt -increasing ocean temperature (warmer water means more evaporation) -ocean acidification which cuts off ocean photosynthesis Coal - correct answers -solid fossil fuels -most abundant -decayed remains from ancient swamps Petroleum - correct answers -derived from decayed plankton and algae -mixed with mud and sand on sea bed Natural gas - correct answers -mostly methane (CO4) -locked in underground formations -burns clearer than coal and oil Nucleus composition - correct answers -protons and neutrons How are nuclei structured? - correct answers -strong nuclear force which is balanced out by the repulsive force between protons Belt of Stability - correct answers -reaching a stable state -unstable nuclei will "roll downhill" into a lower energy state -nuclei do this through radioactive decay Radioactive decay - correct answers -when nuclei are unstable, they emit particles/ energy Alpha decay - correct answers parent nucleus emits 2 protons and 2 neutrons (helium atom) Beta decay - correct answers one nucleon decays into another Beta minus decay - correct answers neutron decays into a proton (electron is emitted) Beta plus decay - correct answers proton decays into a neutron (positron is emitted) Gamma decay - correct answers after some decay event, the daughter nucleus may have excess energy (daughter nucleus emits EM radiation, light) Nuclear binding energy - correct answers -how much energy would it take to disassemble a nucleus Nuclear fusion - correct answers when nuclei combine together Nuclear fission - correct answers when nuclei split apart How do nuclear power plants extract energy from uranium-235? - correct answers -undergoes fission -leads to chain reaction -fission reaction heats water which produces steam -turbine spins and generates electricity -cooling towers shed excess heat What types of waste does uranium-235 produce? - correct answers -fission product waste -actinide waste Pros of uranium-based nuclear power - correct answers -fewest deaths per unit energy produced -no CO2 emissions -potential for innovations Cons of uranium-based nuclear power - correct answers -nuclear waste disposal -nuclear weapons proliferation -frequency of reactor meltdowns and accidents Why might thorium reactors be an attractive alternative to uranium reactors? - correct answers -thorium is fertile not fissile -more abundant than uranium -waste products have shorter lives -resistant to weaponization Renewable energy sources - correct answers -can be replenished on a human time scale LCOE (leveled cost of electricity) - correct answers total cost over factory's lifetime divided by total energy produced over lifetime What roles do economics and politics play in our quest to transition into renewable energy sources? - correct answers Pros of using hydropower - correct answers driven by motion waves/ falling water Cons of using hydropower, especially hydroelectric dams - correct answers -decay of submerged vegetation -ecological disruptions -displacement of people and farmland Ways to harvest solar energy - correct answers -passive heat absorption (absorbing solar energy) -active heat absorption (absorbing and then circulating solar energy) -photoelectric effect -Photoelectric effect - correct answers -photovoltaic cells -solar energy is absorbed- liberates an electron from its' parent atom - leaves behind an electron hole -electrons and holes are mobile which generates an electric current Obstacles of photovoltaics - correct answers -overwhelming power grid -expensive in the short- term -uneven distributions of sunlight Obstacles of wind power - correct answers -wind hot spots -bird/ bat mortality issues -public opposition How can biomass be used as a renewable energy source? - correct answers living plant materials converted into energy Urbanization - correct answers -shifting from rural to urban lifestyles -development of megacities Megacities - correct answers -consist of over 10 million people Pros of megacities - correct answers -efficient Cons of megacities - correct answers -pollution -sanitation Slums and shantytowns - correct answers -"city within a city" -no urban planning -little government presence -hidden "richness" Urban Transportation - correct answers -urban sprawl (dependence on automobiles) -public transit Urban Planning - correct answers -determining how to use and develop land efficiently -design infrastructure to support urban populations -achieve harmony with the local environment Trends in urban planning - correct answers -smart growth -new urbanism Smart growth - correct answers -future-looking -driven by environmental and economic considerations -urban sprawl should be avoided -compact and efficient ways of using existing spaces Characteristics of smart growth - correct answers -mixed-used development -pedestrian and bike friendly -efficient public transit -plenty of green space, local agriculture New Urbanism - correct answers -past- looking -inspired by architectural design principles -mimics pre- automobile city planning -central focal points -often built from scratch Characteristics of New Urbanism - correct answers -30,000- 50,000 people -variety of housing/ jobs -schools, jobs, markets, close to residential areas -promotes walki