Test your basic knowledge |

Praxis Physics Basic Principles

Subjects : praxis, science
Instructions:
  • Answer 50 questions in 15 minutes.
  • If you are not ready to take this test, you can study here.
  • Match each statement with the correct term.
  • Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.
1. Hydrogen and Helium are the most abundant. Than Oxygen - Neon - Nitrogen - Carbon - Silicon - and Magnesium.






2. Joining of two nuclei; occurs under extreme temperatures and pressure. Fusion occurs naturally in stars (responsible for the release of great energy).






3. Two or more atoms held together by covalent bonds






4. Refers to the amount of energy in a system that is no longer available for work. (also used to describe the amount of disorder in a group)






5. A variation of an atom; occur when the number of protons in the nucleus are the same but the number of neutrons are not. Written as the element plus the number of Neucleons (i.e. Carbon -13 (6 Protons - 7 Neutrons)






6. A Machine that converts thermal energy to mechanical energy that can be used to do work






7. Contain two or more substances that are combined but have not reacted chemically. They can be separated using physical methods






8. Isotopes that have not been observed to decay






9. The time it takes for half of the radioactive nuclei in a sample to undergo radioactive decay.






10. 1st (K Shell) = 2 electrons - 2nd (L Shell) = 8 electrons - 3rd (M Shell) = 18 electrons - 4th (N Shell) = 32 electrons






11. Substances that have mass and occupy space






12. The measure of the ratio of a substance's density compared to the density of water.






13. A System that cannot exchange heat - work - or matter with its surroundings. Total Energy & Mass stay constant w/in system






14. A change that results in a different substance. They may release or consume energy.






15. Isotopes that have unstable nuclei and can undergo spontaneous nuclear reactions which results in particle or radiation being emitted.






16. Occurs when an unstable atomic nucleus spontaneously loses energy by emitting ionizing particles & radiation. It is a form of energy transfer. Before Decay = parent nuclide After Decay = Daughter nuclide (s)






17. Branch of Physics that studies the conversion of energy into work and heat. Concerned w/ variables such as temperature - volume - and pressure






18. The capacity for doing work that is based upon position or configuration.






19. Splitting of a large nucleus into smaller pieces






20. Transfer of Energy from a body or system as a result of thermal contact. Heat consists of random motion and the vibration of atoms - molecules - & ions. Higher the temperature - greater the atomic/molecular motion






21. Measurement of the amount of cubic space occupied.






22. Positive; larger than Beta. Because of their large mass they can be easily stopped (even with a sheet of paper.) Can cause severe damage if ingested.






23. Measure of the amount of substance in an object






24. Measure of the amount of mass per unit volume.






25. A system that can exchange heat and work - but not matter






26. Rate at which work is performed






27. Homogeneous mixtures composed of two or more substances that have become one






28. Conservation of Energy (energy can only be transferred - not created or destroyed)






29. AKA Mass Number. The total number of protons and Neutrons in the nucleus of an atoms. Referred to as 'A.'






30. Ratio of the average mass per atom of a sample (which can include various isotopes) to 1/12 of the mass of an atom of carbon -12.






31. The smallest unit of matter that has the characteristics of an element; consists of three main types of subatomic particles: protons neutrons and electrons.






32. When energy is emitted by one body and absorbed by another






33. Attributes such as appearance - color - mass - and volume.






34. Atoms that have an unstable nucleus that has excess energy and the potential to make radiation particles within the nucleus or undergo radioactive decay which can result in the emission of gamma rays. May occur naturally or artificially produced.






35. Can be Beta - Minus or Beta Plus. Beta - Minus: contain an energetic electron Beta - plus: emitted by positrons and can result in gamma photons. Beta particles can be stopped by thin metal.






36. Refers to the particles that are emitted from nuclei as a result of nuclear instability






37. Refers to the energy of an object in motion.






38. Total Kinetic Energy and Potential Energy in a system






39. How do you determine the volume of an irregularly shaped object?






40. Capable of interacting with a surrounding environment and can exchange heat - work (energy) and matter outside their system boundaries






41. This refers to objects that have the same temperature b/c heat is transferred between them to reach equilibrium






42. Measure of gravitational pull of Earth on an object or between two bodies






43. Properties concerned with the constituent particles that make up a substance. Can include: Atomic Number - Category - Group - Period - Block - weight - electron configuration - electrons per shell - phase - density - Sublimation point - specific heat






44. The quantity of energy transferred by one system to another due to changes in a system that is the result of external forces; also can be described as the amount of energy that must be transferred to overcome a force.






45. Energy transferred to a body by a means other than work. (through the process of heat)






46. Refers to the fact that the total amount of energy in a closed system is constant






47. A change that does not result in different substances; when an object changes form but not compostion.






48. Causes an electron to detach from an atom; occurs in radioactive reactions. Three types: 1. Alpha 2. Beta 3. Gamma






49. Substance containing two or more elements; formed by chemical reactions. Can only be separated by a chemical reaction






50. Type of High energy electromagnetic radiation consisting of photons. It rids the decaying nucleus of excess energy after it has emitted either alpha or beta radiation. They can cause serious damage to living tissue. It takes thick lead to stop them.