You are in a windowless car in an exceptionally smooth train moving at constanp;b y:kk* aj+wt velocity. Is;wab y+k*kjp: there any physical experiment you can do in the train car to determine whether you are moving? Explain. ----待选择----yesno 

You might have had the experience of being at-l1r fn r cmen)1pf.3m a red light when, out of the corner of your eye, you see the car beside you creep )ep 1fmn rlfcn1r.m3-forward. Instinctively 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 railroatru*l0t q f-p4xmfyf3 s;v- v8d car, and throws a heavy ball straight up (from hirs- v*f0lt m ft4ypxf83vu- q;s point of view). Ignoring air resistance, will the ball land on the car or behind it?

Does the Earth really go around the Sun? Oay -1w 2g*ly,kr59d itt6h qrrc x9k)lr is it also valid to say that the Sun goes around the Earth? Discuss in view of the first principle of relativity (that there is no best refere5k grq,*6xktrrw l it-)hya9c d2ly19nce frame). Explain.

If you were on a spaceship traveling at 0.5c away frbg 92y*0ayp:n d/oof zom a star, at what speed would the star9ypa2b o * zd0on/y:gflight pass you?

The time dilation effect is sometimes expressed as “moving ivqmde-cak3p k0p , 6:clocks run slowly.” Actually, this effect has nothing to do with motion affemk 6 pc0aidkv:,p3q- ecting the functioning of clocks. What then does it deal with?

Does time dilation m9xb- f 5.xatzqean that time actually passes more slowly in moving reference frames or that it only seem9 -azfxqx. 5tbs to pass more slowly?

A young-looking woman astronaut has gfwbru -+dq uzd4h f*lby+).0just arrived home from a long trip. She rushes up to an old gray-haired man and in the ensuing converdg .hyf+u wu +b*-f) r4zdq0blsation refers to him as her son. How might this be possible?

If you were traveling away from Emt;jt+ t2ek b 3q/1,f llkz srw3/yt( fnl9x6jarth at speed 0.5c, would you notice a change in your heartbeat? Would your mass, height, or wai3 qx; el m( k/y,zr16f/t2nwj3ll+bjft9ktst stline change? What would observers on Earth using telescopes say about you?

Do time dilation and length contraction occur at ordinary speedx1pqymdfln;h- 1x 2 +.mu1kjys, say $90 \, \text{km/h}$?

Suppose the speed of light were infinit 2gyg6vb y6e.ve. What would happen to the relativistic prg 6y6gv2 .vyebedictions of length contraction and time dilation?

Discuss how our everyday lives would v8a6n,kj .90wb aw tvybe different if the speed of light were onla6wbajvt , 8k.0n9wyvy $25 \, \text{m/s}$.

Explain how the length contrf1e*e g ox7:e(mj 7e+kp;hk rlaction and time dilation formulas might be used to indicate that c is the limiting speed in the universe7*pxkle 1 ;(e fkm jg7rho:e+e.

The drawing at the start of this Chapter shows the strym4zf2,czqv7o xh*t 6 eet as seen by Mr Tompkins, 276 xcfhzq4zm, t*ovyfor 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 travel at speeds less than c. Does this put an up7n iv9t7d v; if/ke,hdper limit on the momentum of an ;v ,hn7/t v7dfe9ikidelectron? If so, what is this upper limit? If not, explain. ----待选择----yesno 

  Can a particle of nonzero rest mass attain the speed ofyc/93d3 c v uf tk(,uro2zxut( 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, does this mean that a spring has mo iql137lso 9ewre mass when compressed than whl7 ews3i9 q1loen relaxed? ----待选择----yesno 

It is not correct to say that "matter can neither be created nor destroyed." Whag 04yy)cb0tmh+amgm; t must we say insy b40mgy ;0m+cgm)ah ttead?

  Is our intuitive notion that velocities simply gyl)7 vt o5dkb-:e9v tadd, as we did in Section 3–8, comple95k-dv: o ye7 tlvgtb)tely wrong? ----待选择----yesno 

  A spaceship passes you at a speed sdep(-n.l izw8p.r9hk5gy qhq 1v6th4 ) xi u4of 0.750c. You measure its length to be 28.2 m. How lon4. 6qyiru.- s894hnehtwqd1xp pvzikl5)h(g g would it be when at rest? $L_0$ =    m

  A certain type of elementary particle travels nnakts4m2u /p4mivwt 39t,/eat 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 tt7s.f 2+w)tlsd0ec gygq a.l:he factor $\beta = \frac{1}{\sqrt{1 - v^2/c^2}}$ 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 aw9x4fv( w uaz) speed of $2.50 \times 10^8 \, \text{m/s}$, what would you measure this distance to be? L =    ly

  What is the speed of a pion if its average lifetimyeef;gf) (f p+e is measured 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, a star is 82 light-years away. How fasti;/ sqz )t ps:e,8aflk would you have to travel so that tp;:,)e8skisqazl f/ to you the distance would be only 35 light-years? v =    c

  Suppose you decide to travel to a star 85 light-years away at a speed that te)qd wzfr 3b4oucgt 6pt 5,7e:alls you the ag4 o )czft, 5qwt7rbe:63dpudistance is only 25 light-years. How many years would it take you 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 Earzozyt68y z6:f th is $11.2 \times 10^3 \, \text{m/s}$. 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 st m0kd:ycc3ig;arship Enterprise had just returned from a 5-year voyage c c:k03;ig ydmwhile traveling at 0.84c.
(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. Howmfx 26p4he ;e 8hvxmp. long would it take a spacecraft traveling 0.960c to reach that star fropmp6 4;hvmhe.xfe x28 m 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" spacecraft at a speed of 0.6 7t f(uci5dpg7 gx4:aa60c. It is measured in your frame to be 4.80 m long ax: 7(g54aga7ducit fp nd 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 15 m before it decays? The aqs)iyp 9ys :p5verage liyi:ssp)qy 9 5pfetime, at rest, is $2.6 \times 10^{-8} \, \text{s}$. v =    c

  What is the momentum of a proton traveling a h*(xeho +;q*e mbpd0vt $v =0.85c$? p =    $ \times 10^{-19} \, \text{kg·m/s}$

  At what speed will an object’s relativistic mass be twi7g: rsk45ktpbi 7f7g tce its rest mass? v =    c

  A particle of rest mass nkjv67.tyl(f3 txwzx * 1;cl-rf.blm $m_0$ travels at a speed $v =0.20c$. At what speed will its momentum be doubled? v =    c

  (a) A particle travels at k b92vsmpdnp4/ /v1vm$v =0.10c$. 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 igcri 8uls4tdht q9k4:r(* m1rn momentum of a proton that accelerates
(a) from 0.45c to 0.90c,    %
(b) from 0.90c to 0.98c?   %

  A certain chemical rea ns ++hwbf(x/j n9ne/r /mk9juction 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 procegj qoc;(px3g(2 e dk-zss known as fission in a nuclear reactor, the resulting fragments have a total kinetic energy of about 200 MeV(-zked;c3o xpgq2j( g. How much mass was lost in the process? $\bigtriangleup m$ =    $ \times 10^{-28} \, \text{kg}$

  Calculate the rest energy of amfa0e)l4)5 ,t*u3xs8fl k u)5y l)hkrgclzh gn electron 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 proton,p)s c .7cw9 qbmj8etj in $\text{MeV}/c^2$. $m_0$ =    Mev/$c^2$

  The total annual energy consumption in the United States is about ;fvt/fcl5(, )xp9znune q rk4tkgk22 $10^{19} \, \text{J}$. How much mass would have to be converted to energy to fuel this need?    kg

  How much energy can be obtained from conversion obo g4 +ggdl-;rkcs wgzef ).54f 1.0 gram 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 pmo) gg,etkvk+yp2v/ )article when its kinetic energy equals its rest energy? v = otv pgy/)ke+mk) ,vg2   c

  At what speed will an object's kinetic energy be 25% of its rest energy? v = jcvr,3 n/;0 a n w5efw/oniq8u   c

  (a) How much work is required to accel0 g2fnxs6a.6pz8xk gv erate a proton from rest up to a speed of 08pgg60 .xzka nsvf6 2x.997c? W =    GeV
(b) What would be the momentum of this proton?p =    $ \times 10^{-18} \, \text{kg·m/s}$

  Calculate the kinetic energy and momentum xdi9 +;qei-b gof 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:7fwov*wkf/9;vw w m6c yw qw1 a 750-MeV proton (that is, its kinetic energy is 750 MeV)? 9yw/1wwfv: wmfkoc76 vqw *w;   $\times 10^{-19} \, \text{kg·m/s}$

  What is the speed of a proton accelerated by a potentimt 64- iu*y+rvq-l4d0umesv-kg9zdv al difference of 105 MV? v = ryiv4-sl9veuvdz ug6-0+tmdq -k*m4    c

  What is the speed of an electron whose kinetic eb*1b x :qwyzr9nergy is 1.00 MeV? v =    c

  What is the speed of an electron just before it hits a television screen af m yive2, k:+yycv cmi9-4jnu5ter being accelerated from rest by the 25,000 V of the pic yumv2km-4 +9ev 5y,ij cinyc:ture tube? v =    c

Two identical particles of rest mass, ymozw.h3xel 5v z2y- $m_0$ 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 of a prot 44s5nsw nl9gji/rb4won ($m_0 =1.67 \times 10^{-27} \, \text{kg}$) whose kinetic energy is exactly half
(a) its total energy, v =    c
(b) its rest energy.v =    c

  What is the speed and the momentumn ;)y.o5mmuhq of an 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 kg );mlf;1mjdqy9mwf z8 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 ee,54 vqsok wu*nergy and momentum of a proton ($m_0 =1.67 \times 10^{-27} \, \text{kg}$) 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 nucleushnoiy13 tce 1,lfj 1i/, $^{241}\text{Am}$, 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 momentum for (a) a pk8h q9o/5xpj carticle of nonzerokc/p8 5 xojqh9 rest mass, and (b) a particle with zero rest mass.

  What magnetic field intensity is needed tojflna;em 204 x keep 998-GeV protons revolving in a circle of radius 1.0 km (at, say, the Fermilab synchrotron)? Use the relativistic mass. The proton's rest mass40 jnmea;2 lfx 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 respectaob5w ki*)b 1hshlzd fa+ ,12a to the Earth) observes a metedhs,kaa *21 1abbh)wi 5ol+f zor come from behind and pass her at a speed she measures as 0.50c. How fast is the meteor moving with respect to the Earth? u =    c

  Two spaceships leave Earth in opposite directions, each with a speed of 0.50c )*b36ovchn pdwith respec opb*vn)d63h ct 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 hpy,4t1 zve ;l 0fdrwh,,f e0qtraveling at 0.71c. A second spaceship leaves the first4,0hervple, h01 , fztfd;qyw at a speed of 0.87c with respect to the first. Calculate the speed of the second ship with 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 ydfr*g n)h1t: vessel approach at a speed of 0.60c. The Enterprise comes to the rescue (Fi *yfd rtgn1h):g. Below), overtaking 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 out 2r- xf+yy i-ex8puh0:e cd7ng two escape pods in opposite directions. One travels at a s-uexrp fyd:x8n-c20 7 i gy+ehpeed $v_1 =-0.60c$ 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 s38t* 9kx g.sn8rohkn pame time, rocket B passes Earth moving 0.95c relative to Earth in the same direction. How fast is B moving relative to A when s8t9 .h n8okkx3n*gprit passes A? u' =    c

  The nearest star to Earth is Proxima Centy8 g zcg*s4)9rftba5 asna-r.p svq/)auri, 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, anything traveling faster tha 6kxx/x)p8oqj n about 0.1c is called relativistic - i.e., for which the correction using special relativity is a significant effect. Determine the speed of/6o xx) p8kqxj 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 speed q/fou e g8cc1a;v 7c*q$v$ 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 matter would have b;mk3hbq86 xuto be totally destroyed to run a 100-W lightbulbh6; 8 3mubqkbx for 1 year? $m_0$ =    $ \times 10^{-8} \, \text{kg}$

  What minimum amount of electromagnatx,ek2tklmh8h t) 1 mp;v7v;etic energy is needed to produce an electron and a positron together? A positron is a particle with the same rest mass as an electl 87t2 m, )tkx;ph ;1vmkvaethron, but has the opposite charge. (Note that electric charge is conserved in this process.) 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 head 1 o+if.vae1acar 1ks- on with a positive muon traveling at 50% the speed of lightersk i v+1-fca1a1o a.. 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, an electron, and a neutrino.u)wmtp /t8w( a 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 tuwat p tw8()/mhree particles when a neutron decays at rest. KE =    MeV

  The Sun radiates energy at a rate of dx );/tvoxsisk6u i6, about $4 \times 10^{26} \, \text{W}$.
(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 * a1wwzd4cmf1d(s2 rdnegative charge and 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 jz+mg5ow snxe348y .op+z t8knucleus into its constituents, two protons and two neutrons? The rest masse 5k.zot4n+ym3px8esw+ zg8 ojs 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 the total binding energy of the $^4\text{He}$ nucleus.) KE =    MeV

  What is the percentage increase p7 i1kp 1kfj 1l q:9in)wubhx)in the (relativistic) mass of a car traveling 110 km/h as compared to a9lwkj1ikfq1p1 u7 xh:p)b )i nt rest? [Hint: use the binomial expansion.]$\frac{\left(m-m_0\right)}{m_0}$ =    $\times 10^{-11}\%$

  Two protons, each having a speed of 0.935c imu7 18nm vpyt laple,,j +ygkfbl- 05;i5h,hon the laboratory, are moving toward each other. Deter0hpb7 u 5,nva ,ye8tj-fkhpo, 5+y gmi1;lllm mine
(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 particle with momen svqx 2t.;bo7stum $p$ and energy $E$ has a speed given by $v = \frac{pc^2}{E}$.

  The fictional starship Enterprise obtains its power by combining r5hmbpvk;h/uqy nj 8bp 9 n/5av1o k,3matter and antimatter, achieving complete conversion of mass into energy. If the mm hhn5,/avjp8/9qu5; rnk bp 3kv1boy ass 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 itq97cn1 :mkr26wch qu*nat qs,s kinetic energy is greater than its rest mass t,am qkhq17qru 9:n 2*csw6n c$m_0c^2$ 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 physicsyi8 m+f7sokso9ae dkyyyfz1q zzd . 71;o5(+j believes that he can fit a 15.0-m-long pole into a 12.0-m-long barn if18k(+7d.;7e1ij fdo9 zfm ysoy 5+ay kzsqzoy he runs fast enough (carrying the 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 form two molx9yonw-vb (0i,w8vrc ,y8 ibves of water, the energy released is 484 kJ. How much does the mass of the elements decrease vvv o ,yrxc8-b w,0( w8yiib9nin 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 identicalq/ (uhego 7.gs243kikd3uwzr particles are created, traveling in opposite directions. 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 = do/gqkue 3w.4 7 rsz(u3hkgi 2   c

  An astronaut on a spaceship ts1kx z1b1ncqj3cw)o *g7 hhl2 raveling at 0.75c relative to Earth measures his ship to be 25 m long. On the ship, he eats his3o1w7zhhc) gc21 xkbsqn j*l1 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 awayb+o 3ijb(a7.nupli6pasy )(hfyv 4( i from Earth. You send a laser beam toward the Earth traveling at velocity c relative to you. What do observersu jb isl y7hypn6.ofb((i)ia +av(4p 3 on the Earth measure for the speed of the laser beam?

  A spaceship and its occupants have a totalx* yfnbm5/1qf 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 w5m/ynb* 1qf xfill be converted to energy to accelerate the spaceship 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 lefyf )la4v egkhfy,yub o; :z,b t5b0q+kf8gl)1t Earth at a speed of 0.99c. What is the spaceship's kinetic energy? Compare with the to4lh)k0)b,y1uyg+ a qo8f b:l ,be;k tzyfvfg5tal U.S. annual 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 +ywndw88y mv9xw4ud;6.0 light-years from Earth. Passenger;8d49wymy uwd +vx8wn s 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 speed necessary for this trip? u =    c

  A 1.68-kg mass oscillates onn+ * ole8oclrv q:423puf -jgv the end of a spring whose spring stiffness constant is jrl vp nve:o2g 843q+o-ufcl *$k=48.7 \, \text{N/m}$. 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 masth d3n,s9- 2 hybynjt6s $m_\pi$ 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 $KE_\mu = \frac{(m_\pi - m_\mu)^2 c^2}{2m_\pi}$.