You are in a windowless car in2dqrfo-+c b ;5g;dj cd an exceptionally smooth train moving at constant velocity. Is there any physical experiment you can do in the train djdg+5 ;bdcc-2 r; oqfcar to determine whether you are moving? Explain. ----待选择----yesno 

You might have had the experience of being at a red light when, out of the corno f9w(sib)vl9-8p : cagw*vpner of your eye, you see the car beside you creep forward. Instincti :vo-p 99wg v (p)wsfc*ai8nblvely you stomp on the brake pedal, thinking that you are rolling backward. What does this say about absolute and relative motion?

A worker stands on top of a moving rinfw/f.5 vt1vq,+ fzhailroad car, and throws a heavy ball straight up (from his point of view). Ignoring air resistance, willvv/fi1w+fzfqhn. 5, t the ball land on the car or behind it?

Does the Earth really go around the Sun? Or is it al0wa;+ stw,/d 2bt cxqz7-ssqq so valid to say that the Sun goes around the Earth? Discuss in view of the first princiaws 7, +c dsx-tbq;q20qwz/ stple of relativity (that there is no best reference frame). Explain.

If you were on a spaceshll/b 6kt xtt*t*x m7f.ip traveling at 0.5c away from a star, at what speed would thet l.ttx /b*t6kmxl7*f starlight pass you?

The time dilation effect is sometimes expressed as “moving cloc0 3ze.ick5ep oks run slowly.” Actually, this effect has nothing to do with motion affecting the functioning of clocks. W0 ei3p.co5ke zhat then does it deal with?

Does time dilation mean that time actually passes more slowly in moving referencp 6lz 3d4b(tjgw7(caee frames or that it ow( pal7eb j3d (gct4z6nly seems to pass more slowly?

A young-looking woman astronauwcxw-g4j(fa0nl) xk-t has just arrived home from a long trip. She rushes up to an old gray-haired man xw c-0kxn l4jf(-)gwa and in the ensuing conversation refers to him as her son. How might this be possible?

If you were traveling away from Earth at speed 0.5c, would you noticemrmu1 5;ef s2t a change in your heartbeat? Would your mass, height, or waistt21;fuemm5r sline change? What would observers on Earth using telescopes say about you?

Do time dilation and length contractiw-m uv 9-.o r la7sr q0c/es-c:9mqjaxon occur at ordinary speeds, say $90 \, \text{km/h}$?

Suppose the speed of liu 44tf.kayv d(ght were infinite. What would happen to the relativistic predictions of (v f4k4uayd.t length contraction and time dilation?

Discuss how our everyday lives would be different if the speed of lighk4- rbte rv*/nt were only/r4te *r-bn kv $25 \, \text{m/s}$.

Explain how the length contraction and time dilation formulas might tb8-;iw;cb c 8sx1aq;8yqu( rh xwx8w be used to indicate that8yhxaqbw w1cutr8qsx b;i8 w-c;8(x; c is the limiting speed in the universe.

The drawing at the start of this C o*fxs9lu+.oy3 cjk6 uhapter shows the street as seen by Mr Tompkins, fouxl*s+ujo9y f3ko.6 cr whom the speed of light is $c=20 \, \text{mi/h}$. What does Mr Tompkins look like to the people standing on the street? Explain.

  An electron is limited to trav-x skdlz7b u;0el at speeds less than c. Does this put an upper limit on the momentum of an electls0d7zukb-; x ron? If so, what is this upper limit? If not, explain. ----待选择----yesno 

  Can a particle of nonzero rest ma-oi :.(x21qats s pleuss attain the speed of light? ----待选择----yesno 

  Does the equation $E=mc^2$ conflict with the conservation of energy principle? Explain. ----待选择----yesno 

  If mass is a form of energy, d5oh ik biqs,u8xw:l2 6oes this mean that a spring has more mass when compressed than w6ios liuk q:,b5w28x hhen relaxed? ----待选择----yesno 

It is not correct to say that "mattemq7eu bf6s k v0e7se9l(4 or8ir can neither be created nor destroyed." What must we say instieems4q fb7e o8klvu7r69(0s ead?

  Is our intuitive notion that velocities simply add, as we did in Sectpc5x5,n0ms3bs l n3jdnojii 2*(itw;ion 3–8, compliwp,52 5n3 0o (ic;nj*t lisjbmx3ndsetely wrong? ----待选择----yesno 

  A spaceship passes you at a speed of 0.750c. You measurzdfc9quxm0 sw )4.b +he its length to be 28.2 m. How lohwuc 0sfz 9mbqx4d.)+ng would it be when at rest? $L_0$ =    m

  A certain type of elementary jhs78 :qo dx6-zk l(ttc)vdqq w)*1s xparticle travels at a speed of $2.70 \times 10^8 \, \text{m/s}$. At this speed, the average lifetime is measured to be $4.76 \times 10^{-6} \, \text{s}$. What is the particle's lifetime at rest?
$\Delta t$ =    $ \times 10^{-6} \, \text{s}$

  Lengths and time intervals depend on the factorkp*hiu53stefq w;8o/jq ao4 p+ re+9j $\beta = \frac{1}{\sqrt{1 - v^2/c^2}}$ according to the theory of relativity. Evaluate this factor $\beta$ for speeds of:
(a) $v = 20000 \, \text{m/s}$ (typical speed of a satellite); $\beta =$  
(b) $v=0.10c \;\; \beta =$  
(c) $v=0.20c \;\; \beta =$  
(d) $v=0.95c \;\; \beta =$  
(e) $v=0.98c \;\; \beta =$  
(f) $v=0.999c \;\; \beta =$  

  If you were to travel to a star 125 light-years from Earth at a speed of x hmi0+s55bml $2.50 \times 10^8 \, \text{m/s}$, what would you measure this distance to be? L =    ly

  What is the speed of a pion if its average lifetime is mz t 3.16 c4oxmvd.2w flp5datuxlh2d, easured to be $4.10 \times 10^{-8} \, \text{s}$? At rest, its average lifetime is $2.60 \times 10^{-8} \, \text{s}$. v =    c

  In an Earth reference frame, akq,z,m4k, ypwr1* io a tij7b- star is 82 light-years away. How fast would you have to travel so that to you the distance would be only 35 kt oqpz,wa*k7 1,bji,m-r4yilight-years? v =    c

  Suppose you decide to travel to a star 85 light-bbzi .f)g w:t5years away at a speed that tells you the distance is only 25 light-years. How many years would it take you5t wzb:i.b f)g to make the trip? t =    y

  At what speed $v$ will the length of a 1.00-m stick look 10.0% shorter (90.0 cm)? v =    c

  Escape velocity from the Earth isp) (sjnno9h wj::qbx,s a+oc3 $11.2 \times 10^3 \, \text{m/s}$. What would be the percent decrease in length of a 95.2-m-long spacecraft traveling at that speed? L =    $ \times 10^{-8}\%$

  At what speed $v$ do the relativistic formulas for (a) length and (b) time intervals differ from classical values by 1.00%? (This is a reasonable way to estimate when to do relativistic calculations rather than classical.) v =    c

  Suppose a news report stated that starshi zbix -beu- br27f:*kbp Enterprise had just returned from a 5-year voyage while traveling at -- f*kbb bbuxi27ez:r0.84c.
(a) If the report meant 5.0 years of Earth time, how much time elapsed on the ship? $\Delta t_0$ =    yr
(b) If the report meant 5.0 years of ship time, how much time passed on Earth? $\Delta t$ =    yr

  A certain star is 10.6 light-years away. How long would it take a splr wc.cd(- fx+acecraft travelingl.cdf- cr+( xw 0.960c to reach that star from Earth, as measured by observers:
(a) on Earth, $t_{earth}$ =    yr
(b) on the spacecraft? $\bigtriangleup t_0$ =    yr
(c) What is the distance traveled according to observers on the spacecraft? L =    ly
(d) What will the spacecraft occupants compute their speed to be from the results of (b) and (c)? v =    c

  A friend speeds by you in her "Ferrari q6qy8n+fptl9yv f8o kkf7 s21" spacecraft at a speed of 0.660c. It is measured in your frame to be +yk qf7fksn1 lfovp2 t8 8q96y4.80 m long and 1.25 m high.
(a) What will be its length and height at rest?
$L_0$ =    m
the rest height is    m
(b) How many seconds would you say elapsed on your friend's watch when 20.0 s passed on yours? $\bigtriangleup t_0$ =    s
(c) How fast did you appear to be traveling according to your friend?    c
(d) How many seconds would she say elapsed on your watch when she saw 20.0 s pass on hers?   s

  How fast must an average pion be moving to travel 17n/zgvk rcq0uwq30 h7 5 m before it decays? The average lifetime, at rest, iqzqg07 h7vnwkur0 c/ 3s $2.6 \times 10^{-8} \, \text{s}$. v =    c

  What is the momentum onjkqq5c 4t6o :,4u( ,pkcdmxhf a proton traveling at $v =0.85c$? p =    $ \times 10^{-19} \, \text{kg·m/s}$

  At what speed will an object’s rela8x8mw92ewq ed e7wk0htivistic mass be twice its rest mass? v =    c

  A particle of rest mas m0wc.g.sbjy yq*,es1 d 3i(qfs $m_0$ travels at a speed $v =0.20c$. At what speed will its momentum be doubled? v =    c

  (a) A particle travels ati+ ,hbrc*ixd : $v =0.10c$. By what percentage will a calculation of its momentum be wrong if you use the classical formula?    %
(b) Repeat for $v=0.90c$.    %

  What is the percent change in momen;hi jiub13 t6ttum of a proton that accelerates
(a) from 0.45c to 0.90c,    %
(b) from 0.90c to 0.98c?   %

  A certain chemical reactiontpnd.1u60z7,toet kg, 09bpxe.yncs requires $4.82 \times 10^4 \, \text{J}$ of energy input for it to go. What is the increase in mass of the products over the reactants?$\bigtriangleup m$ =    $ \times 10^{-13} \, \text{kg}$

  When a uranium nucleus at rest breaks apart in the process )-jh+ sj(ebqtz uz6k5)ls,uoknown as fission in a nuclear reactor, the resulting fragments have a total kinetic energy of about 200 M, )6jkhs+toqu)sjzz u5-l(b e eV. How much mass was lost in the process? $\bigtriangleup m$ =    $ \times 10^{-28} \, \text{kg}$

  Calculate the rest energy of an el4cj fla8den w -/)+ftus8gd8x ectron in joules and in $\text{MeV}$ ($1 \, \text{MeV} =1.60 \times 10^{-13} \, \text{J}$).E =    $ \times 10^{-14} \, \text{J} = 0.511 \, \text{MeV}$

  Calculate the rest mass of a protonrhl6n3g8 a9rv lkpm .) in $\text{MeV}/c^2$. $m_0$ =    Mev/$c^2$

  The total annual energy consumptio 18s-op zrs,gmcbij /7n in the United States is about $10^{19} \, \text{J}$. How much mass would have to be converted to energy to fuel this need?    kg

  How much energy can be obtained from conversion of 1.0 grvwp46 b pej5c,am of mass?    $ \times 10^{13} \, \text{J}$How much mass could this energy raise to a height of 0.25 km above the Earth's surface?   $ \times 10^7 \, \text{kg}$

  What is the speed of a particle when its kinetic energy equals its rest wc69 +wne(hbe;u0xr gfuw 2m 2energy? v =gum9 e2hw( f;xwwrbenc 2 60+u    c

  At what speed will a3g9nm 8 0al8bjfg m-l g8tq ujh82oa.f cko*(rn object's kinetic energy be 25% of its rest energy? v =    c

  (a) How much work is required i(-ngs kyt/z8to accelerate a proton from rest up to a speed of 0.997cg 8n/ y(iktsz-? W =    GeV
(b) What would be the momentum of this proton?p =    $ \times 10^{-18} \, \text{kg·m/s}$

  Calculate the kinetic energy and momentukt+r (,mhws 6a ) n9e1dlpjkx (a:0qfhm of a proton traveling $2.60 \times 10^8 \, \text{m/s}$.
KE =    $ \times 10^{-10} \, \text{J}$
p =    $ \times 10^{-18} \, \text{kg·m/s}$

  What is the momentum of a 750-MeV proton (that is thqkcw2 :*xj/, its kinetic energy is 750 MeVq2*j /:ctkwxh)?    $\times 10^{-19} \, \text{kg·m/s}$

  What is the speed of a proton accelerated by a potential difference of 105 MV u5zi0)tk(rq bcb2j ,8vidh c-? v qcvzi()uhc2,5b0t8db krj -i =    c

  What is the speed of an electron whose kinetic 7 vd/g/z.ijaa/uogi(energy is 1.00 MeV? v =    c

  What is the speed of an electron just before it hits a televisi r.nzxv* r:p;aon screen after being accelerated from rest by the 25,000 V of the picture tube? v a v*.xp zn;rr:=    c

Two identical particles of reh;ul+wth-ux o*u py;5 s 4*4wc0xrncjst mass $m_0$ approach each other at equal and opposite speeds $v$. The collision is completely inelastic and results in a single particle at rest. What is the rest mass of the new particle? How much energy was lost in the collision? How much kinetic energy is lost in this collision?

  Calculate the speed ofce-(y ) mwgz5r:eb2 pb a proton ($m_0 =1.67 \times 10^{-27} \, \text{kg}$) whose kinetic energy is exactly half
(a) its total energy, v =    c
(b) its rest energy.v =    c

  What is the speed and the momentum of an,0rikhq he:gw,o 5i4x de q0c4)ed7ka electron ($m=9.11 \times 10^{-31} \, \text{kg}$) whose kinetic energy equals its rest energy?
v =    c
p =    $ \times 10^{-22} \, \text{kg·m/s}$

  Suppose a spacecraft of mass 27,000 kgag4 qy.:bu+mz41 udd0a l d86/lzufzu is accelerated to 0.21c.
(a) How much kinetic energy would it have? KE =    $ \times 10^{19} \, \text{J}$

(b) If you used the classical formula for kinetic energy, by what percentage would you be in error?    %

  Calculate the kinetic energy and momentum of a proton 2.eq y08zb b4*euhjyu($m_0 =1.67 \times 10^{-27} \, \text{kg}$) traveling $7.35 \times 10^7 \, \text{m/s}$. By what percentages would your calculations have been in error if you had used classical formulas?
KE =    $ \text{MeV} \, $ with an error of    %
p =    $ \times 10^{-19} \, \text{kg·m/s}$ with an error of    %

  The americium nucleus, t8jr toh4g0s1$^{241}\text{Am}$, decays to a neptunium nucleus, $^{237}\text{Np}$, by emitting an alpha particle of mass 4.00260 u and kinetic energy 5.5 MeV. Estimate the mass of the neptunium nucleus, ignoring its recoil, given that the americium mass is 241.05682 u. $m_{Np}$ =    u

  An electron ($m_0 =9.11 \times 10^{-31} \, \text{kg}$) is accelerated from rest to speed $v$ by a conservative force. In this process, its potential energy decreases by $6.60 \times 10^{-14} \, \text{J}$. Determine the electron's speed $v$. v =    c

Make a graph of the kinetic energy versus mow:qu a54k xhjfu2rg+)mentum for (a) a particle of nonzero rest mass, and (b) a particle with zer24+5uxqh)jakuf r: wgo rest mass.

  What magnetic field intensity is needed to keep 998-GeV protons revos6 :6ndf1zzs xlving in a circle of radius 1.0 km (at, say, the Fermilab synchrot:ns 6dsx61zzfron)? Use the relativistic mass. The proton's rest mass is $0.938 \, \text{GeV}/c^2$ ($1 \, \text{GeV} =10^9 \, \text{eV}$). [Hint: in relativity, it is still true that $\frac{mv^2}{r}=qvB$ in a magnetic field.] B =    T

  A person on a rocket traveling at 0.50c (with respect to the Earth) observesa.1 y3pj v 1npk*pu9(scw9z py a meteor come from behind and pass her at a speed she measures as 0.50c. How fast is the meteor moving with pp.yc9v1yzw9*(pup k j3s1an respect to the Earth? u =    c

  Two spaceships leave Earth in opposite0mjyw f6*2;+-k iz nalqckbl:a-y kx0 directions, each with a speed of 0.50c wit60zc l ;iy*2+-fb wjk -qy ax:lnamkk0h respect to Earth.
(a) What is the velocity of spaceship 1 relative to spaceship 2? u =    c
(b) What is the velocity of spaceship 2 relative to spaceship 1?u =    c

  A spaceship leaves Earth traveling url fm39 d,dj;+vu+qa a/l.gmat 0.71c. A second spaceship leaves the first at a speed of 0.87c with respect to the first. Calculate the speed of the second ship wfam u +v3j /gml.ud9+q;,lard ith respect to Earth if it is fired
(a) in the same direction the first spaceship is already moving, u =    c
(b) directly backward toward Earth.u =    c

  An observer on Earth sees an alien vessel approach at a speed oe 3 kz9ov hj)/hpub/0of 0.60c. The Enterprise comes to the rescue (Fig. Below), oh03 p) hue9jbovk/oz/vertaking the aliens while moving directly toward Earth at a speed of 0.90c relative to Earth. What is the relative speed of one vessel as seen by the other? u =    c

  A spaceship in distress sends o;ay uva:hb2k3w* -a njut two escape pods in opposite directions. One travelsa b32vu-aj * ahw;:kny at a speed $v_1 =-0.60c$ in one direction, and the other travels at a speed $v_2 =+0.70c$ in the other direction, as observed from the spaceship. What speed does the first escape pod measure for the second escape pod? u =    c

  Rocket A passes Earth at a speed of 0.75c. At the same time, rocket B pa jscr(-wn-ox l tsof0n b5-0n+sses Earth moving 0.95c relative to Earth in the same dires5+-ntl0-jw b on 0r(scfo-nxction. How fast is B moving relative to A when it passes A? u' =    c

  The nearest star to Earth is Proxima Centamocu rhsi :uf)kjx.:k2.dt 59uri, 4.3 light-years away.
(a) At what constant velocity must a spacecraft travel from Earth if it is to reach the star in 4.0 years, as measured by travelers on the spacecraft?    c
(b) How long does the trip take according to Earth observers?$t_{Earth}$ =    yr

  As a rule of thumb, an/o8p7 h ihu:ad;ch 4ssqgbp; (ything traveling faster than about 0.1c is called relativistic - i.e., for which the correction using special relativity is a significanto:hphq4 ihu gas 7p/csb ;d;8( effect. Determine the speed of an electron in a hydrogen atom ($v \approx 2.2 \times 10^6 \, \text{m/s}$) and state if it is relativistic. (Treat the electron as though it were in a circular orbit around the proton.) ----待选择----relativistic not relativistic 

  (a) What is the spee mln2n248a0zr g;rm jm/zjxe.d $v$ of an electron whose kinetic energy is 14,000 times its rest energy? You can state the difference $c - v$. Such speeds are reached in the Stanford Linear Accelerator, SLAC.    m/s less than c
(b) If the electrons travel in the lab through a tube 3.0 km long (as at SLAC), how long is this tube in the electrons' reference frame? [Hint: use the binomial expansion.]L =    cm

  How many grams of matts(g tpe/o)9y ner would have to be totally destroyed to run a 100-W lightbulb fogsyp (n9/teo)r 1 year? $m_0$ =    $ \times 10^{-8} \, \text{kg}$

  What minimum amount of electromagnetic energy is needed to produce an electron a t/ v,+mckstn.f( y;nsik52gsf:t,8 0lqbymw nd a positron together? A positron is a particle with the same rest mass as an electron, but has the opposite charge. (Note that electric charge is conserved in this procqtyb f l50cmv8m(sw 2sk+s.i :t, gkf;/tnny,ess.) E =    MeV

  An electron ($m=9.11 \times 10^{-31} \, \text{kg}$) enters a uniform magnetic field $B=1.8 \, \text{T}$, and moves perpendicular to the field lines with a speed $v=2.5 \times 10^7 \, \text{m/s}$. What is the radius of curvature of its path? r =    mm

  A negative muon traveling at 33% the speed of light collides h0on).p.5 c74 fkvtu0 xjeefuhead on with a positive muon traveling at 50% the spee0hutcp7 .xke e) 4.0jonuf 5vfd of light. The two muons (each of rest mass $m_\mu = 105.7 \, \text{MeV}/c^2$) annihilate, and produce how much electromagnetic energy?E =    MeV

  A free neutron can decay into a proton,e ekep/x;y+ +sby.p -j an electron, and a neutrino. Assume the neutrino's rest mass is zero, and the other masses can be found in the Table inside the front cover. Determine the total kinetic energy shared among the -eyky./ ;+x+ejp bpesthree particles when a neutron decays at rest. KE =    MeV

  The Sun radiates energy at a rate of about l 30j,v;inl5wieqm-f 0 ey vx1$4 \times 10^{26} \, \text{W}$.
(a) At what rate is the Sun's mass decreasing?$\frac{\Delta m}{\Delta t}$ =    $ \times 10^9 \, \text{kg/s}$
(b) How long does it take for the Sun to lose a mass equal to that of Earth?$\Delta t$ =    $ \times 10^{15} \, \text{s}$
(c) Estimate how long the Sun could last if it radiated constantly at this rate.$\Delta t$ =    $ \times 10^9 \, \text{yr}$

  An unknown particle is measured to have a negative charge an5kqmq94 ,f/tls+ 4iknq ji* rcd a speed of $2.24 \times 10^8 \, \text{m/s}$. Its momentum is determined to be $1.07 \times 10^{-22} \, \text{kg·m/s}$. Identify the particle by finding its rest mass.
 ----待选择----electronpositron 

  How much energy would be required to break a helium nucleusl5b 7gr/p rq06-jqlog into its constituents, two protons and two neutrons? The rest masses of a proton (including an electron), a neutron, and helium are, respectively, 1.00783 u, 1.00867 u, and 4.00260 u. (This energy difference is called tg 7 rr0-l6gjbp qq/ol5he total binding energy of the $^4\text{He}$ nucleus.) KE =    MeV

  What is the percentage increase in the (relativistic) mav ql/n -;fvpy-po)b1 lss of a car traveling 110 km/h as compared to at rest? [H)-fvn- /plvl;bo1 pqyint: use the binomial expansion.]$\frac{\left(m-m_0\right)}{m_0}$ =    $\times 10^{-11}\%$

  Two protons, each having a speed of 0.935c in the laboratory, are movin1tap8h-8fwbtx))o fo g toward each 8wpf )t xb81-) ohotafother. Determine
(a) the momentum of each proton in the laboratory, u =    $ \times 10^{-18} \, \text{kg·m/s}$
(b) the total momentum of the two protons in the laboratory,   
(c) the momentum of one proton as seen by the other proton.p =    $ \times 10^{-18} \, \text{kg·m/s}$

Show analytically that a pwqa7a oy 4dt)w a+ z(xs/j(vb/article with momentum $p$ and energy $E$ has a speed given by $v = \frac{pc^2}{E}$.

  The fictional starship Ensb3-a:b; 7yrl8ueorw agd5 a8terprise obtains its power by combining matter and antimatter, oar7g8urlys; :e3bbw -a85 daachieving complete conversion of mass into energy. If the mass of the Enterprise is approximately $5 \times 10^9 \, \text{kg}$, how much mass must be converted into kinetic energy to accelerate it from rest to one-tenth the speed of light?    $\times 10^7 \, \text{kg}$

  An electron is accelerated so that its kinetic energy e4qbij5shl9ge5 2z8 *xyt bh3is greater than its rest mass b4ihs5by8 j2 e3* ehzxt9gl 5q$m_0c^2$ by a factor of
(a) 5.00, v =    c
(b) 999. What is the speed of the electron in each case?v =(1 -    $ \times 10^{-7}c$)

  A farm boy studying physics believes that he can fit a 15.0-ne i;lnz tu,4.m-long pole into a 12.0-m-long barn if he runs fast enough (carrying th;ltu ni4zn. ,ee pole). Can he do it? Explain in detail. How does this fit with the idea that when he is running the barn looks even shorter to him than 12.0 m? ----待选择----possiblenot possible 

  When two moles of hydrogen and one mole of oxygen react to./w 9x4 l*se dujs8bbb form two moles of water, the energy released is 484 kJ. How much dwl4s .d*ujx/bbb s9e8 oes the mass of the elements decrease in this reaction?
$\Delta m$ =    $\times 10^{-12} \, \text{kg}$
What % of the total original mass of the system does this mass change represent?    $ \times 10^{-8}\%$

  In a nuclear reaction two identical partiy q9dimm-pa(* cles are created, traveling in opposite directions.d9m iq-pmy(*a If the speed of each particle is 0.75c, relative to the laboratory frame of reference, what is one particle's speed relative to the other particle? u =    c

  An astronaut on a spaceship traveling at 0.75c relative to Earth measureze/a-/6v,sygstee/k s his ship to be 25 m lk//6gtse,e -vs/ya ze ong. On the ship, he eats his lunch in 23 min.
(a) What length is the spaceship according to observers on Earth? L =    m
(b) How long does the astronaut's lunch take to eat according to observers on Earth? $\Delta t$ =    min

You are traveling in a spaceship at a speed of 0.85c away from Earth. ka:)x h pr9h((bv/xuo You send a laser beam toward the Earth traveling at velocity c relative to you. What do observers on the Eara9k(ox)r b/huxh:vp (th measure for the speed of the laser beam?

  A spaceship and its occ7 pzy7) ,jrxhaupants have a total mass of 150,000 kg. The occupants would like to travel to a star that is 25 light-years away at a speed of 0.60c. To accelerate, the engine of the spaceship changes mass directly to energy. How much mass will be converted to energy to accelerate the s h zp)ry77,ajxpaceship to this speed?    kg
Assume the acceleration is rapid, so the speed for the entire trip can be taken to be 0.60c, and ignore decrease in total mass for the calculation. How long will the trip take according to the astronauts on board?$\Delta t_0$ =   y

  Suppose a 12,500-kg spaceship left Earth at a speed of m9-/av joplf50.99c. What is the spaceship's kinetic energy? Compare with the total U.S. annua o-5/9maflpjv l energy consumption (about $10^{19} \, \text{J}$). KE =    $ \times 10^{20} \, \text{J}$

  A 42,000-kg spaceship is to travel to the vicinity of a star 6.0 light-yea.cb- qf+4t/nud shg ;xrs from Earth. Passengers on the ship want the (one-way) trip to take no more than 1.0 year. How much work must be done on the spaceship to bring it to the speeq x .-+c /4fbgt;unhdsd necessary for this trip? u =    c

  A 1.68-kg mass oscillates on the end oyd v9m1r(t8g*c)vm mvb lc4 .uf a spring whose spring stiffness constantc lty mg d(vv.1)*cmv94mru8b is $k=48.7 \, \text{N/m}$. If this system is in a spaceship moving past Earth at 0.900c, what is its period of oscillation according to
(a) observers on the ship, T =    s
(b) observers on Earth? $T_{earth}$ =    s

A pi meson of rest mangav g-p(7ljkd gl9 .)ss $m_\pi$ decays at rest into a muon (rest mass $m_\mu$) and a neutrino of negligible or zero rest mass. Show that the kinetic energy of the muon is $KE_\mu = \frac{(m_\pi - m_\mu)^2 c^2}{2m_\pi}$.