LUOA's 8th Grade Semester 1 5.18.F - Test: Semester Exam 2023 Questions and Answers

LUOA's 8th Grade Semester 1 5.18.F - Test: Semester Exam 2023 Questions and Answers You are expected to complete approximately ___________________ minutes of school work EVERY DAY, Monday-Friday, in each of your classes. 45 A(n) __________ is a logical interpretation based on observations and previous knowledge. inference What is a theory? A possible explanation of a general principle offered to explain observed facts. To take back something someone stated publicly is to _________ their statement. recant Which experiment of Galileo's was performed on the moon? dropping a feather and a hammer The factors that can change during an experiment are referred to as _________. variables How many independent variables (IV) should you have in an experiment? only one Grandma Hippity Hop is worried about the ice that will be forming on her sidewalk this winter. She doesn't have money to waste on sidewalk salt that is ineffective, so Brenda decides to do some testing for her. What should her control be to test this? same size of ice cubes Convert this number from standard form into scientific notation: 18,900,000 1.89 x 107 Convert this number from scientific notation into standard form: 2.987 x 107 29,870,000 Convert this number from standard form into scientific notation: 0.00045 4.5 x 10-4 ______________ is the extent a measurement moves toward a known value. Accuracy Convert this number from scientific notation into standard form: 9.8 x 10-3 0.0098 Julie is having a swimming party and needs to replace the water that has evaporated from her pool. What metric measurement will she use? liters To convert a smaller metric measurement to a larger one, you move the decimal point to the ________. left Which is the proper way to cite a book using MLA format? Author's last name, first name. Title of book. City of publication: Publisher, year of publication. Medium of publication. How much time are you expected to spend on this class? 45 minutes a day, 5 days a week What should you do if you are going to be away for a couple of days? work ahead and finish assignments ahead of time The metric system of measuring is always used by? Scientists Who was Aristotle's teacher? PLato What greatly affects how scientists (and you) look and interpret evidence? Their worldview. In studying science and the world around us you will find that there are many things that you cannot _____________________ with your senses and test by _____________________________ . observe...experimentation As you work through the scientific method and come to the conclusion that your hypothesis is false, what should you do next? Report your results and try again. with a new hypothesis hypothesis A possible explanation for a set of observations observation use of our five senses to gather information (data) scientific inquiry The process of continuous discovery and building of knowledge in the World of science interpret to understand according to an individual's beliefs assume to suppose as a fact How many independent variables (IV) should you have in an experimen only one Jordan wants to see if earthworms prefer rough or smooth terrain to crawl through. What will be his independent variable? This is what he will change in his experiment. change the terrain What is the controlled variable (control) in an experiment? the parts of the experiment which are not changed in any way The one thing in an experiment that you are trying to measure is called the ________. dependent variable The factor in an experiment that you are trying to measure is referred to as the _____. dependent variable Experiment Scenario: Amelia loves to play golf but hates it when her golf balls go into the water. Some brands seem to soak up so much water that they never quite make it to the green again. She has decided to test her dad's three favorite brands of golf balls to see which brand holds the most water and would hinder her game. Questions: The fact that she is going to use the same kind and amount of water to submerge each ball is an example of a _____________________variable. The weight of each ball after soaking in water for ten minutes is an example of the ________________________variable. The three different brands of golf ball she will use is an example of the ____________________________variable. control...dependent...independent Why is it important to conduct experiments repeatedly? For more accurate results, to ensure the instruments being used to make the measurements did not malfunction, and to cut down on human error. Convert the following number in standard form to scientific notation: 12,450,000,000 1.245 x 1010 Convert this number from standard form into scientific notation: 100,000,000,000,000,000 1 x 1017 Convert this number from scientific notation into standard form: 4.5 x 10-3 0.0045 In a paragraph of no less than three sentences, thoroughly explain how accuracy differs from precision. Remember to use proper grammar and mechanics when writing your paragraph. Accuracy and precision. You need both in science. Accuracy would be like hitting a bulls-eye. Precision would be like hitting the bulls-eye three times in a row. Accuracy is an achievement, but precision would be like you already knew you were going to get there. If you want to measure the distance between two cities using the metric system, you would use ___. kilometers (km) If you were going to have a party and wanted to buy a variety of drinks (soda), what measurement would you look for? liters What is the meniscus? the bottom of the curve when measuring a liquid in a graduated cylinder 3.06 kg = ___ g 3,060 g How many millimeters are on a typical twelve-inch ruler? 305 Jordan decides to go jogging with his Labrador Retriever through the neighborhood to go to his grandmother's house. They begin running East for 50 meters, then South for 45 meters, and then East again for 115 meters to Jordan's grandmother's house. How many meters did Jordan and his Retriever run East? 165 m Find the density of 22.5 mL of mercury in a graduated cylinder with a mass of 306 g. 13.6 g/mL The measurement of the amount of matter in an object is its _______. mass The formula to calculate the volume of a regularly-shaped object is: Volume = length x width x height Calculate the volume of this box: length: 3 centimeters width: 5 centimeters height: 2 centimeters density: 2 g/cm3 30 cubic centimeters If the rectangular tub shown is only filled halfway, how much liquid is present? 21600 cubic inches What is the mass of ethyl alcohol that has a volume of 150mL, if the density is 0.789 g/mL? 118.35 g A unit of mass and weight in the metric system that is equal to 1000 grams is the ________. Kilogram What does the horizontal (x-axis) show on every correct line graph? passage of time Which location has seen the largest population growth and largest forest loss since 1990? Africa According to this graph, plants that were given _____________ grew the tallest. Oscomocote What can we conclude about this student? The student gradually performed better on the Math SAT. Which kind of graph could be used to demonstrate the number of students who like hamburgers, hot dogs, or sandwiches using pictures? pictograph Which graph uses percentages to show how each category relates to all of the data? circle graph Which graph shows the spread of the data from the median or midpoint of the numbers? box-and-whisker-plot Which graph uses a picture to represent a specific quantity? pictograph We know that every object exerts an attraction on every other object and the greater the mass of the object the _______ the attraction. stronger What force keeps the planets in their orbit? gravity The _______________ is the point in an object where there is as much weight on one side as on the other side. This is also called the center of balance. center of gravity In what kind of terms did Newton express his laws? mathematical The larger an object is the _____ attraction it exerts on other objects. greater Newton's first law of motion states that an object at rest will remain ___________________________and an object in motion will remain in motion unless acted upon by a(n) _________________________ force. at rest...outside What is friction? A force that opposes motion between two surfaces that are in contact with each other. Which law of motion is demonstrated when you push off the wall in the pool and move in the opposite direction across the pool? Newton's 3rd law of motion What would be considered a demonstration of static friction? When two surfaces are pressing together but are not moving When you blow up a balloon and let it go it flies across the room. This is due to Newton's ____________ law. 3rd law of motion The parts of two objects that rub together to cause friction are their ___ areas. surface A substance that can be applied to a surface that reduces the friction is called a ___. lubricant A(n) ______ is what scientists call a proposed answer to a problem based on known facts that are used as a basis for further experimentation. hypothesis What was Galileo's conclusion after thinking about this problem? The heavier ball would hit the ground first. A proposed answer to a problem based on known facts that are used as a basis for further experimentation is a(n) ___________. hypothesis What motion was Galileo watching when he became intrigued with the pendulum? a chandelier swinging When an object neither sinks or floats it has ___________ buoyancy. neutral Liquids and _________ are considered to be fluids. gases Which of these is an example of centripetal force? electrons around a nucleus Centripetal force is an ____________ force. inward What one change in a pendulum changes the time to complete a swing? length of string/rope (pendulum length) Who used the pendulum to create the grandfather clock? Christian Huygens What do scientists call the distance to the right or left of the pendulum's normal hanging position? displacement