Experimental physics for students pdf download

To determine the value of low resistance by the method of fall of potential Expt. To calibrate a polarimeter and hence to Mathiesen and Hopkin's method of determine the specific rotation of a sugar projection solution by means of a polarimeter Expt.

To deterrnine the horizontal component balance of the earth's magnetic field and the Art. Precautions to be taken in performing enrploying magnetometers experiments with a potentiometer Expt. To compare the n-ragnetic moments of two Expt. To determine the'e. To measure the magnetic dip at a place.

JZi a milliammeter Expt. To determine the angle of prism by rotation of the prism table. To draw the characteristic curves of a Michelson intOrferometer. To determine the melting point of a solid by means of a Expt. Helmholtz coil To determine the logarithmic decrement of a ballistic Art. In performing an experiment in the laboratory, one is required to revise thororrghly t.

Thus practical classes serve as a sor[ of revision exercises of the theoretical lectures. Moreorrer, laboratory work n-lakes a student methodical, accurate, diligent and trained to rules of - discipline. The overall aims of the physics practical programme are to help the students learn a to experiment i. Measurement of these quantities involves various errors which are enumerated below. This is due to the personal qualities of the workers.

For example, different time keepers in a sport are found to record different times o[ start ancl finish. Inexperienced observers or observers not in a normal state of health make errors of varying magnitude. Such errors may be eliminated by taking mean o[ several observations.

Faulty graduation of an instrument, in the calculated result. In determining the value of g by simple e Pq4lqx E11gls: When a reading is taken along a scale' pendulum. Due to carelessness in this by a constant amount from the true value. Such errors are respect an error in reading is inevitable' This error in eliminated by different methods. In order to avoid such errors the scale' straight determined and correcti. Thus, these e. Using a spirit level and by adjusting the screws' the experiment.

In determining specific heat of solid or levelling is done. Iiquid by the method of mixture, the loss of heat by radiation g Back-lash Error: It occurs when one part of a is allwed to occur and then this loss is corrected for.

Thus Generallythiserrordevelopsininstrumentspossessingnut in an experiment with meter bridge in finding the null and screw arrangements. With continued use, the screw and point, a tapping error is introduced owing to the fact that the nut wear away due to friction and the space within the the pointer which indicates the position is not exactly nut for the play of the screw increases more and more' The situated above the fine edge of the jockey which makes result is that when the screw is turned continuously in one contact with the bridge wire.

This is eliminated by obtaining direction, the stud at the end of the screw moves as usual; two balance points after interchanging the resistance coils. Inspite of all corrections and move fpr a while.

The error introduced on reversing the precautions taken against all possible known causes, some direction of turning is called back-Lash error.

This is avoided errors due to unknown causes occur which affect the by turning the instrument, before taking any reading' always observations. Such errors are called accidental errors. Errors in the same direction. By applying the theory of which the true value of the constant probably lies. Let us now determine the limits within which the errors of u may lie.

The quantities V are the proportional errors f;, ;,i, ii Find the difference between the observed values in nleasrrrernent ot the respeCtive quantities. When each is and the arithmetic mean.

It is called the deviationd' nrtrll-iplied by lOO, the corresponding percentage o[ error is iii calculate the average value of the deviation without given. As the errors in x,U and z may not be in the same taking their signs in consideration' Call this value 6 direction, the errors in u may be less tltan that given in the average deviation.

The probable error is O'B times this maximum error. It is, therefore. The value of n is known. The value of r is to be The probable error is o. If r be measured with an error not exceeding O'OI final value may. Suppose a physical constant u is to be 1.

It is customary that when the variables are to be plotted in a graph, independent variables are plotted as the abscissae I horizontally from left to right and the dependent variables as a p-r bropt , ordinate upwards. The variables plotted along an axis should o u.

For example, in load E elongation graph, the elongation always changes with the o a change of the load. Hence load is the independent variable E , and the elongation is the dependent variable. First select the minimum value of lD a the two variables.

Take the round numbers smaller than the o o a, minimum values as origins for the two variables. In ro 20 30 40 50oC60 70 80 certain cases one or both of the co-ordinates o[ the origin Temperolure in -- may be required to have zero value of the variables, even though the minimum value of the corresponding variables Fig - 1. Therefore' the value of the gas, temperature is the independent variable and pressure is origin for temperature should be O"C Fig. U the dependent variable. First determine the A sample data is shown below: round number greater than the maximum value of the two variables.

Then determine the difference between this round Temperature in "C Pressure in cms. The quotient 35 After marking the These values should be integers, tenths or Then plot the experimental data- Mark each Co-ordinates of the point need nqt be noted unless it is required for quick reference.

Much writing makes the Here the minimum values of temperature and pressure are graph look clumsy. SO'C and 75 cms of Hg respectively. Using a fine h Graphs serveboth iflustrative and analytical purposes. One or two points far away from the curve may be information than tabulated numerical values though it is not ignored Fig.

They are incorrectly recorded. See that as precise- Graphs help identify regions of interest as well as the curve touches the majority of the points and other points the presence of systematic errors. They also emphasize are evenly distributed on both sides of the curve.

When it is a readings that do not agree with others or with the theory. A care to see that it passes through the majority of the points primary function of graphical analysis is to give an empirical Fig. If it is required to two quantities and to indicate the range of validity of this determine the value o[ one variable corresponding to the relation.

In a similar of the ordinate is to be determined corresponding to Lhe way a graphical presentation is the best way of comparing experimental results with predicted theoretical behaviour and the range over which agreement is obtained. Try to anticipate everything that will occur during the oo. Derive the particular relation for the combination of :o.

Tentatively '6 identify the variables with dominant error contributions. Draft a tentative programme for the performance of lhe o 20 40 60 80 too tzo t40 t, , experiment with a detailed procedure for critical or Lood on eoch pon in gms complicat.

Fig 1. From the given point of the Preparation: abscissa, draw an ordinate to cut the curve at a point. From a. Test and familiarize yourself with each instrument or this point of the curve, draw a horizontal line to cut the y- qoql-ponent of the apparalus separately before assembling it. The value of y-axis at this point gives the value Calibrate the instruments where necessary. Assemble the equipment, test that it is functioning Similarly for a given value of the ordinate, the properly and check all zero settings.

Perform a survey experiment running through the com- iii Do not erase or ouentsrite incorrect entries, cross them plete procedure w'hen possible. Use this rehearsal out tuith a single Line and record ttrc correct entrg i to identi-fu ang changes or modifications needed in the beside it. Jrom less tmportant cletails bg emphasizing them' tsi It is adutsabLe to urite on onlg one side oJ a page during elfects.

The errors in these uariables can be estimated. Always be precise in rvhat you write. A precise statement d. Finalize a detailed experimental procedure. Avoid vague expressions such as almost, c-boul; eLc.

Performance: b. Scientific statements should be concise, so use a few a. During the course of an experiment continuously monitor carefully chosen words rather than excessive descrilllion.

The procedure should have built in checks to insure c. To retain control over experimental conditions scientific ations, graphs, emphasis, repetition and summarization are discipline is necessary. This involves following a systematic all aids to clarity. For Lhe purpose of laboratory work trvo note-books- one necessity. IL is essential to control Lhe influence of various indepe- rccorcled in lhe rough note-book. Report on experiments ndent variables.

Always try to isolate each independent should be prepared and written in the fair note-book in the variable to see how the result depends on it. Whenever possible perform the experiment under t. Wrtle the d. Tlrcorg: Here giue Ltrc brieJ ouLline o-f tlrc essent[al e. When keeping a Laboratorg Notebook keep a detailed plrysical principles and tlteoreLical concepts necessaru record of everything that happens as it happens.

Explain clearlg ii Record aLL rano data direcllg into prepared tables. Giue a neat diagram on the btank page to 2. Pictures that are purelg ilLustratiue shoul. A slide callipers consists of a nickel prated steer scare M Results. Wheneuer necessarA, ttrcg shoutd.

Grapl,s slwuld. The grophs should haoe speci,fi. Unless tlrcre is a reason not to, the graph scate sltould- be cltoosen so that the plotted" readings are spread. Calculations shorrld be shousn on the blank page to the leJt. Final result of measwrement should be written at the end in proper trnits. In order to deriue -fiill benefiL from tle laboralory work, it This is the principal scale.

A jaw A is fixed at right angres at is essentfall that the student must knou his uork Jor a one end of the scale. The other jaw B can slide over Lhe scale particular dag beJoreltand and must careJutlg prepare the and can be fixed at any position by means of a screw T. This metter at ltome- movable jaw carries with it Lwo vernier scales v, one on each b. Conting to tlrc Laboratory and.

The i. Under this condition, the a. Tlrc obseruations must be recorded as soon as theg are talcen utitlrout the least delag. Ttrc reading mag be forgotten scale. With such a correcf instrument, when the jaws are in a short time- separated, the distance belween the zero of the vernier scale d.

Euery arithmeticat figure used in recording an obseruation and the zero of the main scale is equal to the distance must be writLen uery distinctlg so that no doubt mag arise as between Lheir edges. The body, of which the rength is to be to its identitg at the time oJ cahculation. Tlte calculatians made to arriue at the fnal restilt must be shoun. The readings of the main and vernier scales gives the ol llrt' lower and upper jaws are in contact.

Through a Iength of the object. The other end of coincide with the main scale zero, there is an fnsl. In such a case, the actual reading of the lrttgth of the rod is such that when vernier reading is zero, scale does not give the true length of the body.

There may be lhe end of the rod coincides with the end of the scale bar. This means that as that of the ordinary callipers. On placing the body between the jaws if the scale ring the upper jaws are inserted inside the cylinders, etc.

To measure the depth of a hollow body, the instrument is b When vernier zero is behind that of the main scale by put in a vertical position and allowed to rest at the end of an amount x mm, the instrumental error is - ve and must be the scale on the rim of the body. The movable jaw is slided added to the actual reading to get true length of the body. Some of the body. Then the usual reading is taken which gives the instruments are provided with arrangement to measure the depth of the body.

The instrumental error, if any, must be taken into consideration in all the measurements. Vernier constant is a meosure oJ the difference in length oJ a scate diuision and a Dernier diuiston in the Lmit oJ the 3 scale druision.

Vcrnier callipcrs. OI cm. Such an instrument is provided with two lower and two Theory : If s be the length of the smallest division of the upper jaws. The product of this vernier reading and the The quantity s - u is called the uernter constant which r, :r'nier constant gives the length of the fractional part. The is a measure of the difference in length of a scale division sunl o[ the main scale reading and the fractional parL taking and a vernier division in the unit of the scale division.

So if L account of the zero error , gives the length of the rod. Take be the reading upto the division of the scale just before the at least five readings and arrange in a tabular form.

Vernierconstant u. OO5 inch. Record this. To be sure, these vt'rrricr zero is in adrrance of the zero line o[ the main scale numbers may be rechecked by moving the vernier to some irrrrl srr1r1 ose [haL the fourth vernier division coincides rvith other position.

Then calculate the vernier constant. Then Lhe error is 4 x r. O2 vernier zero coincides with the main scale zero there is no Ir tclr. If they do not coincide there is an instrumental error. Determine the instrumental error, Tltis instrumentai error must be sublracted from the irpparent lenglh of the body.

When the jaws are in contact, the iv Draw out the movalbe jaw and place the rod between lrurl 'r z. Suppose the jaws. Make Lhe two jaws touch the ends of the rod, aking care to see that they are not pressed too hard or two llr;rl llrr' 4tlr line ie. The drum has a bet,elled end rvith a nrain scale. I circrrk r scale engraved on it. This circular scale contains 5O mrn. This instrumental error must be added to the apparent or IOO divisions. The drum D rvhen rotated, covers or uncovers the scale.

For every turn of the drum, it moves length of the beidy. At the end of the drum there is a friction clutch E. When the screw works in the Note. IJ the radius and cross-section o-f a rod is to be nut Lhe linear distance through whiclt the screw moves is proporlional to the amounl ol rotaLion given to iL.

The edge measured, Llrc dtameter o-f the rod is to be determined at tuso mutualtg perpendicular direction o-f each o. Circular scale is rotated until the same circlrlar scale mark conles - Discussion: against the linear scale. It consists of a the least count of screw gauge. Tl-ris is the pilch o[ i-he screrv.

It the Lerminal. The disl. It is sometimes found that circular corrnt by dividing the pitch by Lhe number o[ divisions in the scale zero and the linear scare zero do noL coincicre t:lrcular scale. The circular scale zero may be in ii Find out Lhe instrumental error by turning the screw advance or behind the linear scare zero by a certai. If the zero of circular scale coincides rvith the zero of as the circular scare leads or r ags as in vernier scare.

The number of main scale zero, the error is to be subtracted and in the divisions in advance or behind Lhe zero of tlie linear scale oLher case it is to be added to the apparent reading. In the flormer case the error is positir. In such a case rvrren screw is turned in one direction, the stud moves Lhe iii Place the rvire breadth wise in Lhe gap between the as usual, studs. By slorvly turning the friction clutch in one direction but when it is rotated in the opposite direction Lhe stud does not move for a whire.

The error that is thus make the studs just touch the specimen. At each place of error. This error can be avoided by turning the screw in the the wire take two perpendicular readings. Take readings at same direction before taking any reading. EXPT 2. Results: Theory : TIte least count of ilre screw gauge is the pitcli divided by the nunrber of clivisions in the circular A Least CounL.

Procedure : i In reference Lo a metre scale li. It rvorks on the same principle as that of a circrr lar vc screw gauge. At the cenler behirrd. P works and lornrs an adjustable centre leg. Table 2 The screw supports a No. A readlng dir. A small scale ctrl crD I a S, ususlly graduated in b millimeter, is fixed to 2 [a] one of the outer legs A b at right angles to the graduated disc.

Tighl-ening will injure the threads. Tlre least count of the spherometer is equal to the pitch iii Mutually perpendicular readings should be taken at ol'llrr: cenlral leg divided by the tolal number o[ divisions in each position of the wire to avoid error due to the rvire not llrc clrcrrlar scale. See Art. Theory : The thickness of the plate is equal to lhe lf the spherometer is old and if Lhe plane of the disc difference in readings of the spherometer when its cenlral slightly oscillates as it rolates, it is proper to count on11, The least count of the spherometer is equal to the pitch of tlie central leg di'ided by the total number of divisions in Results: A Calctttation oJ Least Counl..

Apparatus : A spherometer, a piece of plane glass base The main scale is graduated in ntillintetres suppose. O5 cnt Description of the spherometer : See description. OOO5 cnrs di,ision of the vertical scale. Iread for a complete turn and obsen,e how far Lhe disc ad,ances or recedes rvith respect to the vertical scale.

Divide the pitch by Readings No. This gives the on obs. Take also tl-re reading of the circular heacl 2 against the linear scale. Tabulate the results. Take five sr:ch readings and take the mean value. Alternate method of measurement of thickness. Take the reading of the main and circular scales. For such an old vi By moving up the central screw, sligliily shift the instrurnent, the lbllorving metltod is convenienl.

Thus go on taking reading five times. Take the mean value. Note Lhe division of the circular scale where a is the nlean distance betrveen Lhe outer legs of the against the linear scale. In the above formula, a is, in [act, the length of the side Screw down the central leg slorvly and count Lhe number of of the equilateral triangle formed by the Lhree legs of the rotations of the circular head, till the central leg touches the spheronreter Fig.

LeL x denote OB, the radius of the base plate. Then, if OD be at right angles to BC, The lolal count is lo be done by two instalments-by ilre number of complete revolutions of the disc and Lhe difference of initial and final disc readings.

Thus we obtain Fig. PQ rneets this circle again in S not shown in Fig. We surface with a spherometer. In measuring thi rength of an are on Lhe scale pan and enter tlrcm in lhe note-book.

Then renloue thent one aL a time to their places in LIrc box. Travelling microscope, also known as Vernier microscope, is used in nraking large number o[ accurate measurements of lengths in the laboratory. There are various forms of the instrument, one of which is shown ir,Fig. It consists of a microscope which is mounted on a vertical pillar so that it can slide up and down along the scale 51 by a rack and pinion arrangement.

The vernier scale V1 slides rvith the microscope and serves to determine its position. The vertical scale with the microscope can move about rvithin a groove made on a horizontal base provided wilh levellinS screws and can be flxed at any posiLion by tightening a screw.

On Lhe base just at the border of t. The ntovable base ol Lhe nricroscope is provided rvitl-r anotlter vernier V2. The bases of some insLruments are prorrided witl-r spirit level. The position of the microscope is changed by rack and pinion Fig. For finer adjr-rstment use is made of the scrwes ,lrlt'r The distance through which the microscope rrrrrl llirrailel to the scale The cross-wires in the moves vertically or horizontallS, ssn be read from the scales ilr' ' lirt'rrscd and trre microscope is moved so eye-piece Llia[ the S 1 and 52 rvitl"r the help ol the verniers V1 and V2 moving olr.

By the rvith Lhe nricroscope. The microscope can be filted al out a vt:r'tical nrovernent of ilre microscope, it is focussed on the horizonlal axis.

The nticroscope is then mor. Cross-wires are lltted in Lhe eye-piece which can r ' 1rr7 rrrrrr V2 irre taken. The difference. It is then lirn llr. Tlre ltosition of Lhe carriage C can be read shifted till it is focussed on Lhe other, the line ol;oining the oll'olr tlre scale on the colunrn by means of a rremier V.

The two points being adjusted parallel to Lhe direcLion of motion lrlr:ricolle is providetd rvith a spirit Ievel L on the lop rvhich of the microscope. The dilference betrveen tlte readings for s 'rvcs to shorv when Lhe the microscope positions in the two cases gives Llte distance required. The instrrrm- The inslrument can be used to measure boLh ltorizonlal and vertical distances. To measure the value o[ one division o[ the ttlicronteter colre in Lhe telescope carriage.

The Lelescope is scale. Focus iL and count the nuntber N divisions o[ llror,,ided rrriLh cross- rvires. In measuring the lhe micrometer scale covered by n divisions of Lhis scale. Then the length another and its position of the oblect is d multiplied by the length corresponding to noted from thc vernier.

The difference betweerr 2. A cathetometer is an instrument for accurately Using the Cathetometer. It consisl-s i Before using the cath- of a verlical colurnn AB fixed to a heavy metal sland in such a et. B levelling screws at the base. Along the column a telescope T vertical and the telescope axis is horizontal. To do this. The column the column till the telescope is parallel to the line joining has a scale engraved along one [ace.

The telescope is lrvo ol the levelling screws of Lhe base and by turning these supported by a carriage C rvhich can slide along the column'. Turn the screw attached to t. Next turn the by a microrneter screw E. This carriage D can be clamped to. When rlill the beam oJ the balctncc bc hotlzorttctl? Whal arc llrc requtsltes o-l'tt gaxl balo'ncc? Mtrst be trtrely sensitive' stable and rigid See a text book 4.

Wral is s. Sere theoll' ExPt. Wrry arc lht' u'er'. Disttngulsh betueen mass and u:algltt. It ls an lnvariable quzrntity. Weight rr. As ttre accelcration dtre to gravlty changes fronr place to place, tlrc weiglrt varies. It clecreases rvhen the' bocl. Mrat ts mc'asttt'ec1 bq abalcutc:r'--In 'ss or t'eight'? Here mass is nteasrtred ll1' q6t.

Only the sprirrg balance gives the weight' 3 but tl-re comlllon balance does ttot. This fact is known as "I,lpglg's larv". Doc,s the change ln the ualues oJlergh and. No: such changes only change the turlst- 4. What ts the elfect of change oJ temperahtre on figtdtS? I Wlth the increase of temperature, rigtdity decreases- 3 ro! Dfslfnguish betueen torstonal rlgtdtty r arid. Irlrsional oscillations about a 12 f ,pL -,pit vertical axis. If at any instant Discussions : i The length of the wire is to be measured the angle of twist be 0, the from the point of suspension upto the point at whiclt the Irroment of the torsional couple pointer is attached.

Oral Questions and their Answers 'l'lr e refore, the motion is l. What are shearlng stress and sheartng stratn? What is rigtdttg? What ts its unlt? Frorn l and 2. Z 8nll C -nr4 al;out its axis of suspension. The cylinder will perform suitable clamps, stop-watch, screw gauge, metre scale, etc. The upper end of the wire A is fixed observations calculate the mean period of oscillation' at a rigid support. By means of a detachable screw the cylinder is attached to the lower end of the wire B so that Results: the axis of suspension coincides with the axis of the cylinder.

In some cases the whole arrangement is enclosed A Reaclings Jor the diameter oJ the u;ire' in a glass case to avoid air disturbances. Tabulate as in exPt. Also measure its diameter by Mean radius of the wire. B Readings Jor tle diameler oJ the cglinder Then calculate the mornent of inertia of the cylinder from its Tabulate the result as in exPt. D Length oJ the wire, L. E Readings Jor the time Pertod T. In reference to this pointer, oscillations are 2 counted..

Alternately a telescope is to be focussed from a. How the mass of the spring contributes to the effective iii The e -peimental wire should pass through the axis mass of the vibrating system can be shown as follows.

Consider the knietic energy of a spring and its load iv The pendulum oscillation of the cylinder, if any, undergoing simple harmonic motion. At the instant under should be stopped.

Oral Questions and their Answers. How da the Length and dlameter of the wlre alfect the pertd oJ osctllatlon oJ a torstonal pendulum? See 'Discussion vt ' 2. Does the perlod oJ osctllatlon depend on the omplttude oJ oscfllation oJ the cyltnder? The angle of oscillation may have any value within the elastlc limlt of the suspension wlre.

Hou: ttstll the perlod of osclllatlon be alfected tJ the bob oJ the pendulum be made heotsg? Wlth greater mass moment of lnertia lncreases and te slowly with greater perlod. At this same instant an element dm of the mass m of the spring will also be moving up but with a velocity v which is Theory : If a spring be clamped vertically at the end P, and smaller than vo. It is evident that the ratio between v and vo loaded with a mass mo at the other end A, then the period of isJust the ratio between y and yo.

Draw line"s mass of the spring. The applied force mog is proportional to points. Therefore mg-kl. The spiral spring may be a steel spring capable of supporting sufficient loads. This book consists of a total of fifteen chapters. Authors from eight countries emphasise the same trends despite their cultural and educational differences. The book begins with general chapters describing cognitive processes and how these processes are measured using eye-tracking methods and other psychophysiology parameters and motivation.

Finally, the book concludes the chapters presenting studies in specific scientific fields from chemistry, biology, physics and geology. Resources for Teaching Middle School Science, developed by the National Science Resources Center NSRC , is a valuable tool for identifying and selecting effective science curriculum materials that will engage students in grades 6 through 8.

The volume describes more than curriculum titles that are aligned with the National Science Education Standards. This completely new guide follows on the success of Resources for Teaching Elementary School Science, the first in the NSRC series of annotated guides to hands-on, inquiry-centered curriculum materials and other resources for science teachers.

They are also grouped by type-core materials, supplementary units, and science activity books. Each annotation of curriculum material includes a recommended grade level, a description of the activities involved and of what students can be expected to learn, a list of accompanying materials, a reading level, and ordering information.

The curriculum materials included in this book were selected by panels of teachers and scientists using evaluation criteria developed for the guide. The criteria reflect and incorporate goals and principles of the National Science Education Standards. The annotations designate the specific content standards on which these curriculum pieces focus. In addition to the curriculum chapters, the guide contains six chapters of diverse resources that are directly relevant to middle school science.

Among these is a chapter on educational software and multimedia programs, chapters on books about science and teaching, direct. Dickinson, is an invaluable resource for IB Physics teachers, whether new to teaching the course or a seasoned veteran.

This second edition has been fully updated to align with the latest requirements of the Internal Assessment IA aspect of the IB Physics Guide first assessment Written in plain English with an international audience in mind, it is the ideal teaching and learning resource for both standard and higher levels of the IB Physics course.

To browse Academia. Log in with Facebook Log in with Google. Remember me on this computer. Enter the email address you signed up with and we'll email you a reset link. Need an account? Click here to sign up. Download Free PDF. Faith Bancolo. A short summary of this paper. A pretest-posttest matched group design with experimental and control groups, consisted of 21 students each that undergone matching procedures were used in the conduct of this study.

Descriptive statistics like mean and standard deviations, and t-tests were used to interpret and analyze the data. This effect size can be operationally defined as learning gains due to experimental treatment. Findings suggest that the developed laboratory manual in Physics was found to be effective in enhancing the conceptual understanding of the students during their Physics laboratory class.

Thus, this positive result indicates a strong support for a utilization of the learning material for instructional and institutional use. Introduction The noble objective of Science education poses a great challenge for Science teachers to accomplish significant contributions in the field. Since the national goal for education has been set, educational institutions should align their practices to this goal that would create learning environment employing varied learning activities.

In effect, life-long learners today will i Correspondence: email faith. All Rights Reserved. Instructional materials as one of primary sources of science learning content for both students and teachers can also serve as a primary influence on how teachers should teach science Reiser, et al, The constructivist principle holds that learners actively construct new knowledge by fashioning it to meet their needs and capacities and integrating it into their existing cognitive structure University of Mass.

Physics Education Research Group website, , as cited in Hudgins, Furthermore, according to Duit and Confrey , the applicability of science and mathematics must be student-centered in a way that promotes learning activities which develops acquisition of 21st century skills.

These skills include collaboration and communication, creativity and innovation, critical thinking and problem-solving skills. And to strengthen further the need for developing an instructional material, one of the recommendations of the Accrediting Agency of Chartered Colleges and Universities in the Philippines, Inc. As science educators, we all know that constructing any instructional material aims to provide a better understanding of the subject matter for both students and teachers.

However, the processes used to select those materials are critical and must be properly evaluated in order to provide students and teachers a solid foundation for achievement and successful teaching. Hence, with the purpose of providing relevant material for instruction to the Industrial Technology students taking General Physics, the proponent developed a laboratory manual in Physics to address the need of the students, teachers and the institution.

Because of the dearth of research-based instructional materials for use in physics classroom, this study aims to determine the effectiveness of a developed laboratory manual in Physics for Industrial Technology students. Specifically, it sought to answer the following problems: 1 What are the pretest and posttest scores of the students for the experimental and control group? Moreover, the lack of laboratory manual in a General Physics course paved the way for the development of a learning material that was anchored on Outcomes Based Teaching and Learning OBTL utilizing cooperative constructivist approach and experiential cognitivist learning strategies.

Before this learning material could be utilized in the college, proper procedures of evaluating its effectiveness through research-based study must be accomplished. Material and Methods A. A comparison was made between an intact class exposed to the use of the laboratory manual and another intact class without the developed material.

In particular, the study used pretest-posttest matched group design. According to Dimitrov and Rumrill , this kind of nonrandomized experimental design does not disrupt the existing research setting especially when intact groups were the participants. The reactive effects of the experimental procedure were reduced thus improving the external validity of the design but making the design more sensitive to internal validity problems.

However, these were reconciled by carefully matching the participants in terms of their age, gender, past grades in Mathematics for the Modern World GECMAT which was a pre-requisite subject and both classes were handled by the same teacher. This Physics instructor had atleast 3 years of experience teaching the subject. In connection with this study, the developed laboratory manual was intended for these students since this was one of the courses that require General Physics as prescribed in the prospectus of their College.

The said intact classes were composed of heterogeneous students in terms of intellectual ability. Random assignment was used on which group will serve as experimental and control.