Download Tension in Cable  General Physics  Solved Exam and more Exams Physics in PDF only on Docsity! Physics 220 — Final Exam “t
December 15 2000
This mam consista of 25 probleme on 15 pages. Please check that you have them all
All of the formolas that you will need are given below. You may also use a calculator.
sind = y/r ong 8 me tie tan# = y/r r ¥
average speed = Sittence irersimt 9 = 98 m/s A
average velocity = 7 = lepleceneet *
instentapecus velocity = slope of position venmag time
instantansaus acceleration = slope of velocity versus time
For constant acceleration:
5m my + ut + Lov? v= uy + at w= uf +2a(e — 2g}
F = ma FRE, = us (static friction) Fheiatn = pas ¥ (aliding friction)
Fprcity = Sty G@ = 687% 104 Nats?
a = wy EE = bm? W = Fd coed PE satg = mgh
power = work/At B= mi Ap = impylee = F At
Boring = — kr PE pring = Hex? z= Asin(wt}) v= Auwcos(wt)
ws fk w= avafh alm af f=1/T
For constant engular acceleration:
8 = By + unt + dot? w = uy + at w? = w3 + fa(8 — A)
KE=Ju7/2 befw rola @=a/r usufr oma wath
The next page contalos more formulas.
7:
Preseure = Fore/area Pum =1.0 x 10° Pa Arn = Agty
Py + ogh + oj /2= Py + poha + pol/2
Archimedes principle: buoyant force = weight of fuid displaced
AL/L = oAT
PY = ak? Uj = nr 2
Avogadro's number = 6.02 x 10** particles per mole A=43l J}mole K
KEye = UT /2 k= 14x 10°" 1/K av=QW
W = area under P  ¥ carve W =@a~ Qo Ge/Qe = Te/Tu
w= fi r=1/f y = Asin(2a ft — 2ea/d) y= Acos(Dirft — Brad}
Sots = Srowee/(1bufe} vm yf Piim/h)
5. A bullet of mass 0.024 kg ig fired horizontally with a speed of 75 ms from a bridge
which is 24 m above the ground below. How long does it take the bullet to reach the
ground?
—> kw
fa) Be om ame tt
je
(e} Loe ; L
{d} 0.608 Ox yt on Lat
(6) 0.33 6 Cus
223 = 2.35
ty
6. In class we did a demonstration of tha Doppler effect. Which of the following statements
BEST deocribes this effact?
(a) Moving things emit sound.
Com frequency of a wave as detected by ea obearver depends on the speed To)
BOUrce,
{c) The Doppler effect only applies to sound waves.
(d} All sound waves travel at tha same speed.
{e} The Doppler effect makes the frequency of ¢ sound higher.
T. Find the average speed of an angon atom in tha atmosphere, Assume that the at
mosphere can be treated as an ideal gas (this is actually a good approximation) at 4
tamperature of 300 K. The atomic masa of argon is 40 g {not kg).
{a} 14 m/s 7 i
(b) 190 m/s ve > 2k
fe) 530 m/s F Aue
(d) 31 m/s "
ow Te
. Ze he KO «7%

 zat ey ffé02 we
ve Va yO Dee
& You are a lucky child at Christmas and receive 6 special frictionless skateboard. Ta
tey it out you go te the top of a bill and coast down. Tf the hill ig 12m above the
level ground below, how fast will you ba going when you reach the bottom of the hill?
Ignore air resistance.
iw
a} 15 m/s
ra
(b} 240 m/s mash = t ne
(e] 11 m/s = a
( 98 mp (OR Nath = Bes
(e) 5.6 m/s af —
9. A baseball of mesa 0.15 kg ig threw with an initial speed of 35 m/s, You are an
extremely good batter, and hit the ball directly back towards the pitcher. If your bat
imparts an impulse of 15 kg — m/s" to the ball, what is the apaed of the ball just after
it leaves your bat?
_ ms
APs Tas puta OR oA,
fa} 100 m/s y
(b} 15 m/s Aw For ee feu
fe] 3 m/s “ at
‘d) 65 m/s “asf.
a . H7rt 63244
fe) 20 m/s ve 2 [Po ——__
10. A plank is balan: dn two supports aa shown below. The mass of the plank is 25 ke,
and its total length is 3.5 m, The support ou the left exerts an upwarda force F, on the
plank, and the support on the right exerts an upwards force of F'n. Find F;. Assume
that the mass of the plank is distributed uniformly.
2.5 >
=
2.7m
———
he
(a) 130N Vw A
Cy eT beat pout
{c) 4501N F anal DW tyae
(a) 38 N f 44) 70
(2) 190.N F (2.7) wl 88
a a 2etFF 7)
WA  a
an x at
= fia
15. The water pressure in the pipes in your house is 4.0 x 10° Pa. If one of the pipes
springs @ small leak, what is the speed of the water as it sprays out of the leak?
(Potm = 1.0 105 Pa, Suater = 1000 kg/m?) <0 J hea
21 o/s 1 £ gh, t F pa”
(b) 28 mje Papyeet kya BAP 2 Tae
(c} 4.8 m/s al
£ £ par,”
(6 ows oer = flere é vf 2
4 oxeg®
pn?
S$) ptfm fi
P.axeo 
Wh: LM ee
:
16. Consider a piece of metal which is 1.2 m long. If it is cooled by E7G, the length
decreases by 2.2 x 1074 so. Find the coefficient of thermal expansion.
fab 1d = lol yc
fe} 1.9 x 109 72°C og = i, AT "La a
ty
17. Imagine that your are siti room full of oxygen molerples at 300 K. If the mom is
10x 10x23 m°, find the number of axygen molecnles in the room. Pi, = 1.0 x10? Pa.
{a} 40
(b) 4.0 x 10+
40x19 ‘py~* er
PY. at fue
ar
2) 12x 10 * a
) ia 1 Roe: 3% 4 gaxre
yinte > ae
fda = wie ast 27
= 42x
———ar
18. Ifa piston containing an ideal gas is compressed and beat is allowed to flow ia or out as
necessary a0 as to keep the temperature fixed, what will be the nature of the resulting
haat flow?
9) Heat will flow inte the piston from the guzroundings.
(b)_ Heat will Gow out of the piston into the surroundings. 2
{c) There will be no heat Bow inta or out of the piston.
19. You like te ride rollerenasters. Your favorita one hae a circular shape with radius 20 m.
When you are at the top, you fel aa if pour weight is only 6 third of your true weight.
eee ee et
{a} 14 m/s 4
tb) 130 m/s ma v= a
{ce} 1.6 m/s f
(a) 51s
yrs
Ge
ni  2 ws 3
—_ 3
= fleas
—
20. The earth has a radius of 6.4 x 10° m and completes one revalution ebout its axis in
24 hours, Find the speed of a point at the equator.
{a} 1.7 x 10° m/s
b) 570 m/ _ 2 2h 2
Gas VENER
fi)
(9 2  2m bE 2 70%
24: 6060
9