One watt is equivalent to one joule second Smart rocks are considered for ballistic missile defense The asteroid that killed the dinosaurs exploded because it got very hot from the impact Kinetic energy can be measured in calories You have 10 tungsten bulbs and each uses 100 watts You leave them all on for an hour The energy used is 1 kilowatt hour The kinetic energy of a bullet per gram is within a factor of 2 None of the above A bullet at sound speed 1 000 ft s 0 01 calories or watt hours 40 joules Hybrid vehicles run on electric power and gasoline Which of the following is true Power is energy divided by time What is the main reason hydrogen driven vehicles haven t replaced gasoline ones Hydrogen is too difficult to store in an automobile Compared to an equal weight of gasoline U 235 can deliver energy that is greater by a factor of approx one million Which of the following contains the most energy per gram Uranium Which is least expensive for the same energy delivered Coal The kinetic energy of a typical 1 gram meteor is approximately equal to the energy of 10 grams of gasoline Coal reserves in the U S are expected to last for hundreds of years A limitation of all electric automobiles is Low energy density per battery Solar power is about choose all correct 1 kw per sq meter 1 GW per sq km The efficiency of an inexpensive solar cell is 14 A human running upstairs can briefly use the power of approximately 1 horsepower A 12 oz can of soda has about how many calories 150 Calories Electricity from a AAA battery costs the consumer about 1 000 per kilowatt hour Electricity from a wall plug costs the consumer about 10 cents per kilowatt hour The energy per gallon not pound of liquid hydrogen compared to gasoline is about 3x less Most of the hydrogen we use in the U S comes from manufactured from fossil fuels or water Power or Energy Horsepower Power Kilowatt hour Energy Watt Power Calorie Energy Energy Units 3 calories joules kilowatt hour Power Units watts kilowatts horsepower sometimes calorie per second If you double the energy content of a kilogram of gas the temperature of the gas doubles About how fast are molecules in air moving 1000 ft sec Temperature is the measure of average kinetic energy In a bucket of water the instantaneous speed of the molecules is the closest to approximately 1000 feet per second A refrigerator operating in a room warms the room A refrigerator with its door open is operating in a room It warms the room A table has the same temperature as the air above it That means that the molecules in the air and in the table have the same average energy A gas heater warms a room mostly through convection The velocity of sound increases when the temperature increases If a gasoline engine produces a hotter explosion then the efficiency of the engine should go down A cup full of water and made of plastic feels warmer than one made of glass because plastic conducts heat less than glass The atom with the fewest number of protons is hydrogen A large nuclear power plant delivers energy of about 1 gigawatt Ice melts at 0C How many atoms are there in the width of a human hair About 125 000 Heat flow through empty space no atoms present occurs through radiation The linear hypothesis is widely used even though it is not proven The speed of sound is approximately 1000 feet per second Entropy measures disorder Put a hot glass in cool water The glass shatters because the outer surface of the glass contracts rapidly but the inner part doesn t Sea level is rising from global warming The main cause is expanding sea water Molecular motion stops at 0K Energy in the Sun is produced primarily by fusion The mass of the nucleus is closest to 99 of that in the entire atom The temperature warms by 2C That is approx the same as 4F Radioactivity in the Earth leads to All of the above Heat a room using the least energy by using natural gas to run a heat pump There is almost no hydrogen gas in the atmosphere because it escapes the Earth s gravity At Mach 10 if all the energy of a meteorite went into heating the meteorite its temperature would be about 30 000C The New Orleans levees failed because they were weaker at the thermal expansion joints If temperature rises by 5C 9F then the rise in sea level will be about 12 feet For a typical auto the fraction of the gasoline energy wasted as heat is about 80 The temperature in the sun is not well defined When a material is cooled Some materials contract and some expand The melting temperature of an object is usually equal to its freezing point Absolute zero is the temperature of nothing When a liquid boils the increase in volume liquid to gas is typically a factor of 1000 If the temperature of a gas in a container goes from 0C to 300C double Firewalking is similar to water on a saucepan For gasoline to explode it needs to be mixed with oxygen To be more efficient the temperature difference should be as large as possible LD50 refers to a lethal does A major reason that your body is radioactive is that you eat radioactive carbon in your food The primary cause of death from the Hiroshima bomb was the blast from the bomb Fission fragments are among the most dangerous kind of radiation Wine made from fossil fuels is not radioactive because there is no carbon in such wine If the half life of an element is big that means that it decays slower than one with a small half life Mueller wears a wristwatch with tritium in the watch hands because no radiation emerges from watch hands Most of the elements found on the Earth were created in a Supernova Explosion The fraction of the US population that dies from cancer is 1 in 5 Watch dials all radioactivity creates light Choose all the items that derive from radioactivity helium volcanic lava warmth in deep mines After four half lives the surviving tritium atoms are removed Compared to completely new tritium atoms they are expected to live exactly as long One rem of radiation dose takes how many gammas per square centimeter about 2 000 000 000 Which require the larger dose cancer A siervet is how many rems 100 Cancer is lower in Denver because We don t know why The number of deaths from the Chernobyl accident is about 24 000 Radioactivity is used in smoke detectors Neutron Activation is used to search for rare atoms Dirty bombs may be less of a threat than people fear because once spread out the rem level drops below the radiation illness threshold Radioactivity in the Earth is responsible helium we use in
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