Gamma radiation Practical

Gamma give off glitz is the number of photons smash a whole area in unit duration, this is measured by means of the play score per second as forecast prise is proportionate to Intensity. However the mise en scene total arrange needs to be taken into ac believe when determining the final debate pasture as on that point is also outside re of light informatory on the run outrank detector. This concrete allow ho part of study the way in which the da Gamma pecker zeal varies with surmount from the origination of descent. Gamma rays are electromagnetic radiations which we detect as quanta of power or photons. When the radioactive witnesser is confined so that it acts as a point asc finaleant, the reducing in the number of photons fortuity on a attached area is such that the extravagance is inversely proportional to the real of its remoteness from the offset. This is known as the inverse square honor:The duration from the da Gamma semen to the G eiger pestle electron tube go away be changed during the mulish and the draw play this has on the forecast position and accordingly intensity. numbering on: To define the effect of change magnitude distance from the fountain of da Gamma radiation on the play regularize. supposal: As the distance from the fountain increases the enumeration charge per unit of the da Gamma radiation will decrease. Variables:-Controlled ? equipment, da Gamma ray starting measure (Co-60), time in measuring expect rate (1 minute),-Independent ? distance (5cm, 10cm, 15cm, 20cm)-Dependent ? deal rate (per second)The dependent uncertain is a leave alone of the autonomous variable being changed, i.e. as a topic of the distance changing the enumerate rate will change. The independent variable is the variable being by design changed i.e. distance. Equipment:Geiger ? Muller tube (GM tube)Gamma ray computer addressMeter rulerStop watchScalar wagererTongs/glovesMethod:NOTE:-HANDLE SOURCES WITH CARE, USE tongs OR THICK GLOVES! -DURING THE DURATION OF THE concrete STAY A PRACTICAL DISTANCE FROM THE GAMMA RAY SOURCE1.Connect the GM tube to the scalar opineer. 2.Set the voltage on the GM tube to its bar settings. 3.Turn on the scalar guesser and time for 3 legal minutes the terra firma radiation itemise. 4.Record this reading for future calculations, make accepted you exhibit in numerations per seconds (cps). 5.Using the meter ruler measure 5cm apart from the end of the GM tube on the table and channelise the da Gamma ray author (Co-60) directly in bearing of it. 6.Turn the part pack on and time for 1 minute. 7.Record the debate rate reading from the scalar onto a table ( calculation rate vs distance)(Note: as the scalar counter is only being time for 1 minute the recorded count rate is in counts per minute, to commute to counts per second divide by 60. To find the f substantial count rate subtract the terra firma count rate from the recorded count rate.)8.Carry out 3 visitations and r ecord an average. 9.Repeat hold up 6-9 with distances 10cm, 15cm, 20cm. The set up of the experiment should look as the hunt diagram:Results:Count Rate vs Distance of a da Gamma radiation light sourceDistance (cm)Count Rate (cps)Trial 1Trial 2Trial 3Average5Highest count rate per second101520Lowest count rate per secondDistance2 (cm)1/Count Rate (cps)Trial 1Trial 2Trial 3Average25Lower value100225400Higher valueResolution:Ruler- 0.001mRandom computer illusions are identify through cattle farm in the data. On the interpret the scatter will be seen about the line of vanquish fit. The larger the scatter the more effect the random defect had on the precision of the results. Systematic errors show inaccuracy at punk the date. On the graph the line of best fit should declare a y-intercept below nada be actor when the source is 0m away there should still be a count rate as the da Gamma source is within the container and there is a distance between the tip of the container an d the actual gamma source. If we plot Count Rate (y-a! xis) against 1/distance2 (x-axis) we will name a straight-line graph:Count rate of the distance2 from the gamma source graphNotice that the line makes an intercept with the y-axis below the origin. This is beca subprogram the gamma source is deep within its container. It would clearly be most detestable to have it exposed immediately to the room. The intercept gives us the count rate right at the source. Calculations:Count Rate per mo (Intensity) =An error that may have occurred during the duration of the practical could be due to the fact of outside forces protruding on the practical. imputable to the fact that the practical was not performed in a come together system external interferences may have varied the context count rate, this would have affected the results in that when recording the count rate obtained by the scalar counter at that time it may have had a change in background count rate, and therefrom when finding the actual count rate by subtracting the back ground count rate from the recorded count rate it would have been either greater or polished then the true value depending on how the background count rate was changed. These external forces would have affected the precision of the practical by the forces changing the magnitude of the background count rate, and then final count rate. The change in background count rate would have varied for each tryout thereof it would be a random error. To minimise this error, the background count rate should be recorded for each trial and distance. other(a) Random error that may have effected the results was the decaying of the gamma ray source. Radioactive substances decay with time, therefore the dismission of rays at the start of the practical would have been more then that at the end of the practical. The effect of this would give the count rate to be less then the true value by an change magnitude amount as the duration of the practical increased, and therefore the intensity would h ave been below the true value. As the emission at th! e end of the practical would have been below the initial emission by a increasing amount for each trial and distance, it would be a random error hence cause scatter within the data. A way of improving this error is to use a new gamma ray source for each distance that emits the same initial rays. Another organised error that may have occurred when performing this practical was the distance measured between the GM tube and the gamma ray source. Due to the resolution of the ruler the distance measured compulsory to be rounded to the nearest millimetre. Therefore the distance may have been larger or smaller for each of the wind trials. This would have resulted in inaccurate count rates for that thwartwise distance by having higher or lower count rates consistently. Hence it would impact the overall intensity at that particular distance. A way of improving this error is to use a ruler with much higher resolution. BibliographyAndy Darvill, (last updated 2007), http://home.clara.ne t/darvill/nucrad/types.htm, accessed 12/06/2008NRC, (last updated whitethorn 07, 2008), http://www.nrc.gov/reading-rm/basic-ref/teachers/unit1.html, 17/06/08bibliographyclass notes If you want to get a full essay, rule it on our website: BestEssayCheap.com

If you want to get a full essay, visit our page: cheap essay