5 Most Frequently Tested ACT Science Topics

A lot of students get a little nervous when they see that the ACT has a science section. But Im not a science person! they moan. But theres a very important distinction between the topics on the ACT Science Test and any other science test you’ve ever taken. The most frequently tested ACT Science topics focus more on what you can do when given certain information, rather than what you know before coming into the test. Though you need to be familiar with scientific terms to succeed on the ACT Science Test, the test’s topics also revolve around certain skills. In this post, well look at the most frequently tested ACT Science topics so that you know what to expect on test day. (Ill also point you in the right direction so that you can learn more about each topic and raise your score.) The Scientific Method The scientific method is the key underlying concept behind all science data found on the ACT. Google Dictionary defines the scientific method as â€Å"a method of procedure that has characterized natural science since the 17th century, consisting in systematic observation, measurement, and experiment, and the formulation, testing, and modification of hypotheses.† This widely accepted definition guides all valid scientific research. When carried out correctly, the scientific method yields useful, reliable results. Beyond the dictionary definition, the scientific method involves a number of procedural steps. In a nutshell, the steps are as follows: Observe some kind of scientific phenomenon. Describe what you’ve observed and the evidence of scientific facts you see. This description is called a hypothesis. Use the hypothesis to make predictions about what might happen under certain circumstances. Test those predictions by conducting science experiments to see if they’ll come true. If the results of the experiment challenge your hypothesis, repeat steps 2 through 4 again. Come up with a new hypothesis based on both experiment results and your original observation, and test it with a new experiment. Keep repeating steps 2 through 4 until the experiment proves one of your hypotheses. Once an experiment proves your hypothesis, your hypothesis can be reported to the scientific community as a valid theory. Of course, if your hypothesis is proven to be true immediately in the first experiment, then steps 2 through 4 don’t need to be repeated and step 5 isn’t necessary. Sometimes scientists get lucky and prove their hypothesis on the first experimental try, but more often than not, they don’t. Multiple experiments are usually needed before a hypothesis can become a proven theory. Knowing the scientific method will help you immensely on ACT Science questions that require deductive reasoning. You will sometimes be asked to identify a fact that is probably true, based on the data you see. At other times, a question may present a new observation or variable that was not mentioned in the passage and you’ll need to use the logic of the scientific method to infer the impact of the new data. Beyond those specific question types, the ACT incorporates knowledge of the scientific method comprehensively throughout the Science section. Every ACT Science passage and question set revolves around experiments and/or data collected from experiments. A fluency in the scientific method will allow you to take in ACT Science information with confidence and good comprehension. Reading ACT Science Charts Think of this as the ‘treasure hunt.’ Unlike similar questions on the ACT Reading Test, finding the right answer on the ACT Science Test depends on your ability to read charts, rather than passages. The key to success lies in recognizing labels. Skim the questions first, marking any term that looks important. Once you’ve matched a term in the chart to a term used in a question, you know exactly where to look for the answer. The rest of the information (most of it useless) will no longer confuse you or stress you out. Using ACT Science Charts The chart treasure hunt is over. For this question type, you’ll be given a scenario (ex: a variable in the experiment has changed) and have to use the chart to figure out the possible outcome. Though you’re making an educated guess, the chart will provide all the information you need to answer the question successfully, so dont let your guess stray too far from what you see. ACT Science Graphs While scientists use graphs to visualize data and see patterns in their results, graphs can present unique challenges to the ACT test taker. Questions involving graphs will likely ask you to use both a graph and a corresponding chart. As long as you’re focusing on the keywords mentioned in the question, the excess data should not confuse you. Even in such a busy graph, a question will typically ask you about a single line of data. What Comes Next? These questions will ask you to decide what the experimenter should do next. The key to these questions is knowing what the experiment is trying to do. Again, they dont require any deep knowledge of science, only strong reasoning skills and an ability to tune out inessential information. If we look at the first paragraph, we see that scientists want to know about high altitudes and the effects of the air pressure changes. If thats what the scientists want to learn about, our next step needs to have something to do with high altitudes and air pressure. Comparing and Inferring This last question type appears only with the the Comparing Viewpoints passage on the ACT Science Test. Ever do a compare/contrast activity in English or history class? If so, you know what you need to do to answer these questions correctly. If not, it all boils down to finding similarities and differences in the two opinions. The hardest topic for many students is the inference questions. To improve your inference skills, spend extra time analyzing your results after taking a timed practice test. Good practice tests provide detailed explanations for each answer. If you consistently make mistakes with inference questions, analyzing the right answer will help you build the skill you need to succeed. ACT Science: Scientific Terms Bonus! You can find definitions for the following terms and study them on our ACT Flashcard mobile or web app! The ACT Science section will occasionally include questions in which the answer requires science knowledge that is not provided in the passage. Here is a list of basic scientific topics that the ACT might test. But don’t panic! Anything tested will be on a very basic level (something you might have learned in an introductory class or even remember from middle school), and you will only see a few questions per test that require any outside knowledge at all. To get some more tips on ACT science practice, follow this link for strategies, questions and explanations! Biology classifications: genus, species (e.g. knowing that lizards are mammals, reptiles or amphibians) human anatomical systems (circulatory, digestive, respiratory) eukaryotic and prokaryotic organisms photosynthesis pollination metamorphosis genetics (allele, genes, chromosomes, X and Y chromosomes) proteins DNA RNA ribosomes mitochondria chromosome genotype osmosis phenotype dominant and recessive traits crossing over of dominant and recessive alleles mitosis meiosis cellular division phases (interphase, etc.) Chemistry understanding (and balancing) chemical equations and reactions atom nucleus ion molecule solute solution solvent reactant product solubility atomic mass solid, liquid, gas pH acid base viscosity condensation evaporation electrons protons neutrons atomic number atomic mass molar mass isotopes solid, liquid, gas and melting, boiling, freezing points (very generally speaking; not specific to any particular substance, except maybe water) important elements (e.g. water is H20) Physics velocity acceleration polarity buoyancy waves amplitude frequency wavelength charges (like charges attract; opposite charges repel) circuits (capacitor, resistor) amperes volts convection conduction radiation kinetic energy potential energy gravitational potential energy mechanical energy density Earth and Space metamorphism (state change) layers of earth erosion altitude air resistance orbit terrestrial planet/gas giants Other Science Terms independent variable dependent variable control hypothesis endothermic exothermic ectothermic matter mass Thats all for now, ACT scientists. Good luck, and dont let those graphs and charts psych you out! Unless otherwise specified, all images from Wikimedia Commons: LadyofHats, Emichan Miraceti, Sharon Bewick, Mats Halldin, Brazosport College

A Lab Report On Experiment 17 Experimental Error - 3850 Words

A Lab Report On Experiment 17: Experimental Error (Lab Report Sample) Content: Students Name:Instructors Name:Date:A Lab Report On Experiment 17 Experimental ErrorAbstractThis lab report covers the concept of errors and two experiments on DC of a common emitter amplifier and amplification of AC signals. The types of errors, their sources, classifications and ways of reducing errors in laboratory experiments are described. The experiments were conducted using SK10 boards and analysis of the results carried out. The certainty of the measured values was calculated and the absolute and relative error calculated too in this report.DeclarationThis laboratory report is my original work, except where due acknowledgement is made in the text, and to the best of my knowledge has not been previously submitted any other institution.Table of Contents TOC \o "1-3" \h \z \u Abstract PAGEREF _Toc464407602 \h 1Declaration PAGEREF _Toc464407603 \h 11.0 Introduction PAGEREF _Toc464407604 \h 21.1 Objectives of the experiment PAGEREF _Toc464407605 \h 21.2 Theoretica l background PAGEREF _Toc464407606 \h 21.3 Ways of reducing errors PAGEREF _Toc464407607 \h 51.3.1 Reducing systematic errors PAGEREF _Toc464407608 \h 51.3.2 Reducing random errors PAGEREF _Toc464407609 \h 62.0 Materials and procedures PAGEREF _Toc464407610 \h 62.1 Apparatus PAGEREF _Toc464407611 \h 62.2 Procedure for using SK10 board PAGEREF _Toc464407612 \h 72.3 The procedure for practical work: part I DC bias of a common emitter amplifier. PAGEREF _Toc464407613 \h 72.4 Procedure for Practical work: Part II- Amplification of AC signals PAGEREF _Toc464407614 \h 104.0 Discussion and Conclusion PAGEREF _Toc464407615 \h 144.1 Discussion PAGEREF _Toc464407616 \h 144.2 Conclusion PAGEREF _Toc464407617 \h 145.0 Work Cited PAGEREF _Toc464407618 \h 151.0 Introduction1.1 Objectives of the experiment 1 To familiarize with the type of errors, their sources, ways of reducing them, and how to report uncertainty. 2 To be able to build a common emitter amplifier circuit, test its DC bias settin g and amplify AC signals.1.2 Theoretical backgroundScientific procedures to test or discovery of something in the laboratory will always involve comparison of measured quantity with predetermined values of similar quantity. The difference between the measured value and the absolute value is called an error. The error may arise from various sources like environmental changes, while performing the experiment, which some are impossible to avoid and can only be minimized by employing refined techniques or improved instruments. The indication of how much error the measurement might contain makes the results of the experiment that involve measurement to be complete. This means that the knowledge of the types of errors, ways of reducing these errors and proper ways of treating data is required in order to obtain estimate of the degree of uncertainty in measurements. An error is therefore, an uncertainty with measurements, which cannot be eliminated but can only be minimized. CITATION Ric11 \l 1033 (Richard S. Figliola)Errors can be categorized into systematic errors and random errors. Systematic errors describe errors in the output reading of an instrument that are consistently on one side of the correct reading. That is either all the errors are positive or all are negative and they tend to shift the mean of data toward a single direction. Sources of this error include; systematic disturbance during measurement, effect of environment on the instruments (or modifying imputes), bent meter needles, calibration error, drift in instrument features and lastly poor connections practices of the instruments. An error resulting from calibration is always there in an instrument and the value is usually indicated by the manufacturer. CITATION Ala01 \l 1033 (Morris)On the other hand, random errors are those that fluctuate from one measurement to the next, yielding the results that are distributed about a certain mean value. For example, timing of the oscillation of a pendulu m when measuring the period, changes in temperatures and in-line voltages. Sources of this error include; human error, errors resulting from variations in definitions, uncontrollable fluctuations in the inputs conditions in the measurements, electrical noise , lack of precise definition of the quantity being measured and many other unpredicted conditions/ situations. These errors can be minimized by taking several values from the same experiment and find the mean value or by improving the experimental techniques.Mathematical expression governing this error:X= x xWhere x is the mean, x is the uncertainty in the measurement and x is the experimental measurement to be reported. CITATION Dep15 \l 1033 (Electronics)In an experiment, precision and accuracy are essentials to obtain almost error free data. Accuracy is how close the measured value is to the true value or theoretical value; while precision describe the spread of these measurements when repeated. This means an experiment wit h high repeatability has high precision, and can result into high accuracy results. The figure1 below illustrates the difference between accuracy and precision.Figure 1: illustration of accuracy and precision CITATION Dep15 \l 1033 (Electronics)The numbers that can be read directly from the instrument in addition to the estimated value is a reflection of the precision and is called significant figure. The error usually has one significant value hence no need of expressing it in scientific form. When multiplying or dividing, measurement values, the least significant figures in the measurement will be equal to the number of significant figures in the final answer. On the other hand, when adding or subtracting, the number of the decimals in the measurements is the main factor that determines the number of significant figures of the final answer.1.3 Ways of reducing errorsIt is of paramount important to minimize errors in an experiment for high precision and accuracy. This will make th e data acquired more reliable. Several methods have been device to reduce errors depending on the nature or type of the error and their sources.1.3.1 Reducing systematic errors * Systematic errors can develop over a period of time due to wear in instruments components. Recalibration more often gives a full remedy to calibration error. * Observing proper measurement practices would aid in reduction of this error * Use of improved and more intelligent instruments. The equipment should have smallest possible uncertainty. * Making maximum use of available scale and measuring the sum of known number of items for the small values that are mot up to instruments resolution.1.3.2 Reducing random errorsA random error displaces measurements in an arbitrary direction because of the nature of the sources of this error, which makes it unpredictable and inconsistence. Some of the ways to reduce this error include: * Minimizing human error by avoiding parallax * Taking repeated measurements and the n finding the mean, * Careful connection, grounding, reducing of nodes and connector to minimize electrical noise and * Having consistency in measurement techniques.In the following section, an experiment were conducted to build an emitter amplifier circuit, test its DC bias setting and amplify its AC signal using SK10 boards. SK10 board is designed for prototyping electric circuit, in which the conductors are arranged in parallel and the electronics can be inserted to make contact with the conductors. The components are connected by use of a short wire.2.0 Materials and procedures2.1 Apparatus 1 DC power 2 Function generator 3 Oscilloscope 4 Digital multimeter 5 SK10 bread board 6 Transistors BC109 7 Resistors 8 Capacitors2.2 Procedure for using SK10 board * The parallel tracks on the outside of the board was use for power supply * The wire connecting the power supply to the circuit together were twisted to minimize electrical pickup * A coloour scheme was used for wiring * The sho rtest possible length was always used to connect between components to avoid making big loops * The integrated circuit was wired around * The circuit was always built up one section at a time. Then this part was tested to see if it works first before continuing.2.3 The procedure for practical work: part I DC bias of a common emitter amplifier.A basic transistor amplifier known as a common emitter amplifier was built using transistor BC109 as shown in the circuit belowFigure 2: A circuit for pat I CITATION Dep15 \l 1033 (Electronics)Step 0: oscilloscope calibration * Channel 1 and channel 2 of the oscilloscope were calibrated. The test waveform was ensured that they appear as expected.Step 1: power supply connections * Two long wire, a red and a black, were taken, their ends were striped and were twisted together. * One end of the red wire was connected to the positive terminal of power supply and the other end of the black wire to the negative supply. * The other end of each wire was connected to one of the parallel sets of line along the edge of SK10. The red wire was put onto the top line and the black wire onto the bottom line. * Using the oscilloscope with proper scope probes, the power supply was set to 15 V and this voltage was checked if it was seen along the positive supply rail on the SK10.Step 2: Base bias * A note of the percentage and absolute tolerance of all resistors used in the experiment were made using the resistor colour codes. These values were put in the table. * Resistors R1 and R2 were connected on the figure 2. The top lead of R1 was attached to the positive supply rail with the bottom lead into one of the central conductors of SK10. ...