Our site includes quite a bit of content, so if you're having an issue finding what you're looking for, go on ahead and use that search feature there! Get your answers by asking now. The maximum possible efficiency of a heat engine. The change in the balls momentum is, A 100-kg astronaut ejects 4 g of gas from her propulsion pistol at a speed of 50 m/s. A thermometer calibrated in the Celsius scale and a thermometer calibrated in the Fahrenheit scale are used to measure the same temperature. When they have fallen halfway down, they have the same, A moving object does not necessarily have. D. depends on the ratio between the exhaust and intake temperatures. His power output is, A weightlifter raises a 200-kg barbell through a height of 2 m in 2.2 s. The average power he develops during the lift is, A 90-kg llama has an average power output of 80 W. The minimum time the llama can go up a hill 500 m high is, A horse has a power output of 11 hp (746 W) when it is pulling a cart. E. 101 kPa and 15 lb/in2 are both correct. Still have questions? We'll assume you're ok with this, but you can opt-out if you wish. When an additional gram of air is pumped into the container and there is no change in temperature, the new pressure is, The pressure on 100 liters of helium is increased from 100 kPa to 400 kPa. When heat capacity is measured per mole of a substance, instead of measuring it per gram, it is the molar heat capacity. The periodic table helps us to classify and compare various elements on the basis of their chemical behavior. The buoyant force on the soap is. Molecules are, in general, farthest apart from one another in. The air in a room 5 m long, 4 m wide, and 2.5 m high has a mass of, A 400-kg concrete block is 1 m long, 0.6 m wide, and 0.3 m high. The specific heat capacity has units of J/gºC. The specific heat capacity (\(c\)) of a substance, commonly called its specific heat, is the quantity of heat required to raise the temperature of 1 gram of a substance by 1 degree Celsius (or 1 kelvin): \[c = \dfrac{q}{m\Delta T} \label{12.3.4} \] Specific heat capacity depends only on the kind of substance absorbing or releasing heat. The heat needed to warm 8 kg of water from 20°C to 70°C is, The specific heat of ice is 2.1 kJ/kg°C. Which of the following formulas expresses the relationship between the pressure and absolute temperature of a gas sample whose volume is fixed? If the samples all have the same volume, the one with the greatest mass also has the greatest. The balls speed is 8 m/s when it has gone 4 m. The magnitude of the force is, The 2.5-kg head of an ax exerts a force of 80 kN as it penetrates 18 mm into the truck of a tree. What never changes when two or more objects collide is, A bowling ball rolling in a level ground at the speed v strikes a basketball at rest. Report: Secret Service agents asked to relocate with Trump, Fox paid 7-figure settlement over bogus conspiracy story, 'DWTS' crowns new champion and viewers are not happy, Burt's Bees apologizes for offensive holiday ad, David Maas, NBA halftime showman, dies of COVID-19, Summers 'skeptical' about student loan forgiveness, Repairman who found Hunter Biden data closes shop, Education Dept. The average pressure of the atmosphere at sea level corresponds to which one or more of the following? A. strike the container walls more often. It can exert three different pressures on a horizontal surface, depending on which face it rests on. The heat of fusion of lead is, A heat engine absorbs heat at 127°C and exhausts heat at 77°C. This category only includes cookies that ensures basic functionalities and security features of the website. Vol. It’s not possible to present values for all compounds. 6789 Quail Hill Pkwy, Suite 211 Irvine CA 92603. Out of these cookies, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. These cookies will be stored in your browser only with your consent. Specific Heat If you are searching for a reference table listing specific heat capacity of metals and compounds, this article will be a useful read. Which of the following is not true of molecular motion in a gas? Join Yahoo Answers and get 100 points today. The melting point of water is 0°C. Different substances have different heat capacities. ? We hope you are enjoying ScienceStruck! what happens when radium-226 is converted to radon-222. Sign up to receive the latest and greatest articles from our site automatically each week (give or take)...right to your inbox. The point to be noted here, is that the values presented here are those for metals, at 25° Celsius. The speed of the ax head when it strikes the tree is, A 1-kg object is moving at 10 m/s. Its value depends on internal structure of molecules that make the substance. A sample of a gas is expanded to twice its original volume while its temperature is held constant. A Celsius thermometer and an absolute thermometer are used to measure the temperature of the same gas sample. As it moves, the total momentum of the rocket and its exhaust gasses, To prevent it from tumbling in flight, a projectile such as a football is sent off spinning. The volume occupied by 320 g of brass is, The density of air is 1.3 kg/m3. More the degrees of freedom, more is the heat capacity of the element or compound. This value is always larger than specific heat capacity. Necessary cookies are absolutely essential for the website to function properly. The numerical reading on the Fahrenheit thermometer. The temperature of a gas sample in a rigid container is reduced. We also use third-party cookies that help us analyze and understand how you use this website. The physics of a heat engine cannot be used to understand the operation of a. D. removes heat from a region and carries it elsewhere. 583 K. An ideal frictionless engine takes in 10 kJ of heat per second when it operates between 500 K and 400 K. The following ScienceStruck article will cover some information related to metalloids. The Celsius equivalent of this temperature is. Since temperature is a measure of the kinetic energy of a substance, the amount of heat required to raise it, is directly proportional to its internal degrees of freedom. To double its kinetic energy, its speed should be increased to approximately, A total of 4900 J is expended in lifting a 50-kg mass, The mass is raised to a height of, The height above the ground of a child on a swing varies from 0.5 m at the lowest point to 2.0 m at the highest point. Since this is a combustion reaction, heat flows from the system to the surroundings- thus, it … Copyright © Science Struck & Buzzle.com, Inc. The maximum speed of the child is, The linear momentum of a 400-kg giraffe galloping at 5 m/s is, A ball whose momentum is mv strikes a wall and bounces off. The physical principle involved is, When a skater pulls in her arms to turn faster, her angular momentum. D. may be smaller or larger than that on the Celsius thermometer. I the two cars stick together, the wreckage has an initial speed of. Octane is a hydrocarbon and an alkane with the chemical formula C 8 H 18, and the condensed structural formula CH 3 (CH 2) 6 CH 3.Octane has many structural isomers that differ by the amount and location of branching in the carbon chain. Which of the following is (are) not a unit of power? removes tool for defrauded students, Chrissy Teigen gives first interview since pregnancy loss, ER nurse: Some patients still think COVID-19 is a hoax, Synagogue fined for massive maskless wedding. Well, we're looking for good writers who want to spread the word. The density of brass is 8 × 103 kg/m3. C. the smallest particle of a substance that is representative of the substance. In order for an object to sink when placed in water, the object's average density must be. Its maximum efficiency is, If it is to be 40 percent efficient, a heat engine that exhausts heat at 350 K must absorb heat at a minimum temperature of, An ideal frictionless engine takes in 10 kJ of heat per second when it operates between 500 K and 400 K. The work that the engine does per second is. Rolling a ball up an inclined plank requires an amount of work proportional to the, An object that has linear momentum must also have, A gold ball and a ping-pong ball are dropped in a vacuum chamber. It is mandatory to procure user consent prior to running these cookies on your website. In biology class today my teacher played a porn video to show what they were talking about Should I talk to the principal to get her fired. D. There is a definite average direction of motion at a given temperature. If the average speed of the hydrogen molecules was originally v, their new average speed is, In order to double the average energy of the molecules in a gas at 200 K, its temperature must be changed to, Fifty kJ of heat is added to a 10-kg piece of lead at its melting point of 330°C and 2 kg of lead melts. The heat capacity of the calorimeter (also known as the “calorimeter constant”) is 837 J/ºC. Which of the following quantities is always the same to all observes?