Average Force - General Physics - Solved Exam, Exams of Physics

Download Average Force - General Physics - Solved Exam and more Exams Physics in PDF only on Docsity! Physics 220 - Final Exam a December 12 2001 This exam consists of 25 problems on 15 pages. Please check that you have them all, All of the formulas that you will need ara given below. You may also use a calculator. sin? = y/r cos? = afr tan? = y/x I * cverage peed = Mgmt gy = OB mY average velocity = 7 = “ememest - x instantaneous velocity = slope of position versus lite instantaneous acceleration = slope of velocity veraua time For constant acceleration: z= 2g + we + dat? v= uy t+ at vl = wf + Qa{z — 2) F = ma FRilion = H3N (static friction} Fyriccin = fex N (sliding friction} Fyrovieg = SEY G = 667% 10-1 Nm? /ug? a, = fr KE = bm! W = Fd coad PE yauity = tgh power = work/At j= nit Ap = impulse = F At Faring = — hr PEapeing = bkx? z= Aain(wt} v= Aw cos(iet) w = yfk/m w= Yolk w= 2nf f=1T For constant angular acceleration: & = fy + ont + ba? a = uh + of wt = af + Boff - &) KB=iwt/2 baie tale @safr wor asafr wHdft The next page contains more formulas. Pressure = Forre/area Pum = 1.0 < 10° Pa. Ath = Age Pye pgty + pot /2 = Pet agfig + po /2 Archimedes principle: buoyant force = weight of fluid displaced AL{L = eAT PV =nRT 0, =3nAT/2 Avogadro's number = 6.02 x 10** particles per mole R=6.31 J/molke-K KEg, =SKT/2 SLA KWAK | AU Q-W W = area under P— V qurve W=e—-Qe Qr/Qe = Te/Ty v=fa T=l/f y = Asin(ax ft — 2rz/A) p = Acos(2xfi — 2rzf A) fou = feore((Li w/t) v= YT /(m/E) 5. A block of mass 1590 kg slides down a tramp. There i6 friction between the block and the ramp, and this makes the block glide at a constant speed. What is the work done by Friction ag the block slides from the top of the ramp to the bottom? — 15m (a) 15,000 J l wt wach = Me a ( lixi®) vee () 42x 108 J Le: 1s (F,8)- IS Ll] 7 “m4 a Ss I Pm > 22K © €. A block of mass 55 kg is hanging from two cables as shown below. Find the tansion in the cable on the night. Note that the angles which the cables. make with the ceiling are nto? the same. o 0 45// Th ne ein 5 - n a Ty He 8S Typ sete T wh (a) 550 N — 1 BP Ose (b) 330 N Ty co 30> Ty cn ds > fe © ae )_ 380 N ak oan) F i pe = Ea w 5 & we + i f w a 7. A hockey puck of mage 0.23 kg is sliding op a very eclippery horizontal icy surface. Of the puck has an initial speed of 60 m/s, and slides a distance of 2200 m before coming to rest, find the coefficient of kinetic friction between the puck and the ice. {a} 0.73 (b) 0.008 Ae AK E 40 fe) 0.947 ‘ (d) 0.12 , pa be be cor 083} e™ 4 f L v WG 9 og3 94 8. An arrow is shot with an initial spesd of 62 m/s at au angle of 60° with respect to the horizontal. What ig the speed of the arrow when it reachea the maximum height on ita trajectory? Ignore air resistance. => fc) sero fo peed a ( 9, A clown of mass 75 kg is pulling down om a rope ax shown below. The rope is connected to pulleys, and eventually exerts a force sideways (horizontally) on the clown's feet. The clown pulls harder and harder on the rope until his feet just begin to slide aut from under him, Pind the tension in the rope at that instant. The coefficient of static friction between the elown's echoes and the floor is p, = 0.25. (by 740 m/a , (c) 180 N Tta- myo A= mgt (d) 250 N (e] 88N 14. The figure below shows the displacement as a function of time for 4 mae connected to Wapring, 43 it undergoes simple harmonie motion. At what point is the kinetic energy a maximum? A ‘ : fa) Point 4 d tha St Point C {d) Point D fe} Point E 18. One of the pipes in your apartment springs a smal] leak, anc the water sprays out at @ speed of 16 m/s. What is the water pressure inside the pipe? (Par = 1.0 x 10° Pa, fuoter = OOO kg/ sie) (8) 2.3 x 10° Pa, ng Rt o 4 BIER Py pe f “ps oy fd} 28 x10" Pa {e} O.3 x 104 Pa ” Re Bese, hye 4 {iden (G -— #4 L3xro® Pa eT —— 10 16. A cup initielly contains ice and water in equal amounte (0.50 kg each) at 0 °C, Heat ia then added to raise the temperature of the entire systers to 25°C, How much heat wes added? The latent heat of melting is 3.4 x 10° J/kg and the epecific heat. of {liquid} water is 4200 J/(ke — 70}. fa) tld 1) Oe Qual + Qu c} 2.8% 1 (dj) 43 = WF J - eL + fon, FAR IE AT fe} Ll x 10* J t g. 50 (3 yd) B US5.9) Pou (28) : ' = ftw’ + Lorv ~ 2, Feo T __ —————_—— 17. A piston of volume 1.7 m? contains 4.5 moles of a monatomic ideal gas at 300 K. Find the pressure of the gas. (a) 1.0% 10" Pa (b) 11x 104 B 4 fe) 6.6 10 Fa_. Dye “ eT fd) 8.0% 10? Pa i . H fe) 2.6% 10° Pa ll 18. Ifa piston containing an ideal gas is expanded and heat is allowed to flow in or out aa netesgary £0 ac to keep the temperature fixed, what will be the aature of the resulting heat flow? <7 fa) Heat will fow into the piston fom the surroundings. sy (b) Heat wil flaw out of the piston into tha surroundings. (c) There will be no heat flow into or out of the piston. 18. An ideal reversible heat engine opexates between reservoirs at 650 K and 250 K. If the engine extracts 3500 J of beat from the hot reservoir, how much work is done? (a) 3500 J = Tu J 4 fb} 1600 J - _ fe} 4100) W = ay Qe w td) 400 J de Qe. % Act Qu hl = Oy ~ &? Qy Ct ‘£,) zw [900 TT - aor ~ Fe — es