PHYSICS. Time allowed: 90 minutes. Section A is a set of questions on data analysis. It requires work on graph paper.

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Baldric Mosley
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1 PHYSICS EXAMIATIO FOR ETRACE SCHOLARSHIPS JAUARY 7 Tie allowed: 9 inutes Section A is a set of questions on data analysis. It equies wok on gaph pape. Section B consists of nine questions. Attept as any as tie allows. Use the notebook(s) povided to wok out you solutions. Clealy indicate each question nube and please highlight you final nueical answes (including units) by, fo exaple, undelining o faing the. Coect appoaches, thoughts, and ethods will be aked, even if the final answe is incoect. o negative ak will be given fo wong answes. Section A is woth 3% and Section B 7%. The nubes in backets at the end of the questions ae the aks fo coplete answes. Standad booklets of fundaental constants o foulae, povided by you school, can be used. Howeve, the lists on the next page should be enough fo answeing all the questions. Calculatos ae allowed to be used. Fundaental Constants Electon chage e.6 9 C Electon ass e 9. 3 kg Gavitational constant Plank s constant Speed of light Gas constant G 6.67 h 6.63 c 3. R 8.3J K 3 kg s 34 kg 8 /s ol s

2 Futhe Useful Constants Gavity Mass of the alpha paticle g 9.8.s kg Wate density Density of ion w Fe 3 kg kg 3 Boltzann constant Astonoical unit k.38 3 AU.5 J K Ångstö Å = Electonvolt Avogado nube ev.6 A J ol Tepeatue convesion T T o C K Useful Foulae PV kt PV nrt n A M n dx t v t t dt a dvt dt T a v s t s ut t at t vt u at t E kin v p GM Epot E gh qq F e k pot E hf c f h L B p t / t F PA GM E c g R V A U IR Q CU E UQ Q It I i U i p q f

3 SECTIO A Expeiental Data Analysis A etal tank, filled with g of hydogen gas, was heated, while its tepeatue and pessue wee onitoed. The values wee ecoded nine ties. T ( o C) P (kpa) a) What is likely to be the uncetainty ( e P, eading eo) on the pessue due to the esolution of the eading? [] b) Wok out the tepeatue values on an absolute (Kelvin) scale. [] c) Daw a PT (pessue against tepeatue) diaga. Label the axes, and add eo bas to the data points to indicate the uncetainty on the pessue data. [5] d) The ideal (o pefect) gas law, PV nrt, indicates a linea elationship between the pessue and tepeatue of an ideal gas. Do all the nine easueents see to follow this law? [3] e) Daw a line that fits the accepted easueents and ead its gadient. [4] f) One ole of hydogen gas weighs g, that is, the ola ass of the hydogen olecule is M = g ol ; and R is the univesal gas constant (see the list of Fundaental Constants ). Using the foula nm, evaluate the poduct nr. [4]

4 SECTIO B [5] High up in the ai, a balloon aiship is ising with a constant speed of u.7 s when a bag of ass 5kg is thown out of it with a hoizontal speed of w.4 s. What will be the kinetic enegy of the bag t 4 s late? (Ai esistance can be ignoed.) [5] Two electonic devices, R and R, ae connected in paallel to a battey, as shown in the left cicuit below. The eadings on the aetes ae I 3 A and I 5 A. What is the eading on the aete when the two gadgets ae connected in seies, as shown in the ight cicuit, with the sae battey? 3 [5] The adius of the cicula path of an electon about a agnetic field line is.. What is the de Boglie wavelength of the electon if the agnetic field stength is B 3 G? 4 [5] In an expeient with thuliu-68, a adioactive isotope, the initial count ate was easued to be counts pe hou. Afte 3 days, the count ate had dopped to 4 counts pe hou. How long would it take fo the count ate to dop fo 4 to 4 counts pe hou? 5 [5] What is the atio between the angula speeds of the second and hou hands of a clock?

5 6 [5] 9 4 In a nuclea collision, 4 Be and He fuses into 6 C. What is the othe paticle that is geneated? 7 [5] A thin optical lens of focal length 3 c fos an iage of a catepilla of length cawling towads the lens. How long is the iage of the catepilla when its head is at a distance of fo the lens? 8 [5] Spica, the only fist-agnitude sta of the constellation Vigo, is 6.4 illion AU (astonoical units) away fo us. How any yeas does light take to tavel fo Spica to Eath? 9 [5] When the distance between single point chages q and Q is d, the electostatic foce between the is F. What is the foce on Q when eight point chages, each with chage q, ae aanged aound it at gid points A to H as shown, whee point chage A is halfway between gid points C and G? (Each of the ten indicated distances between neighbouing point chages equals d.)

Unit 6 Practice Test. Which vector diagram correctly shows the change in velocity Δv of the mass during this time? (1) (1) A. Energy KE.

Unit 6 Practice Test. Which vector diagram correctly shows the change in velocity Δv of the mass during this time? (1) (1) A. Energy KE. Unit 6 actice Test 1. Which one of the following gaphs best epesents the aiation of the kinetic enegy, KE, and of the gaitational potential enegy, GE, of an obiting satellite with its distance fom the