You are in a windowlesspq/ox. h) 8rrkt*x li3 car in an exceptionally smooth train moving at constant velocity. Is there any physicaxtri8xo.r3l)/hk *qp l 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 a red light when, out of the corafqk,a y;aw dhmr8z 0m;ip9.8ner of your eye, you see the car beside you creep forward. Inst8wm;98ra kp .mqzay0id h fa;,inctively 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 movin7d gl65qimk c,g railroad car, and throws a heavy ball straight up (from his point of view). Ignoring air resistance, will the ball land on the 6g 7lq k,mdci5car or behind it?

Does the Earth really go around the Sun? Or is it also valid to say -ifo:.j p35runmyf 5zthat the Sun goes around the Earth? Discuss in view of the first principle of relativity (that there is no best reference frame). f.pyif5r-n5zuj3m: o Explain.

If you were on a spaceship traveling at 0.5c away from a suy fptyn.w86 a73s( xoh9pnd ,tar, at what speed would the starlight pass .wn89p7u6xhpsd( , yt3onfay you?

The time dilation effect is sometimes expressed as “moving cly, -hvyp+ rxu qyvf648ocks run slowly.” Actually, this effect has nothing to do with motio y-+vpy8yrv 4x q,ufh6n affecting the functioning of clocks. What then does it deal with?

Does time dilation mean that time actually passes m sqk1xg/h)x j)ore slowly in moving reference frames or that itgj x))1/hksqx only seems to pass more slowly?

A young-looking woman astronaut has just arrived home frx m20 vnmkdd7mmtajk .( 0ut75om a long trip. She rushes up to an old gra.vktnm7 mdatj 75 (2k0 u0mdmxy-haired man and in the ensuing conversation refers to him as her son. How might this be possible?

If you were traveling away mp zotauqh x: l1at6cp+ .5o./from Earth at speed 0.5c, would you notice a change in your heartbeat? Would your mass, height, or waistline change? What would observers on Earth using telescopes say about lamuo .t56/x :paq.+zptohc1 you?

Do time dilation and length contraction p+4 wf lhk:1q 0d;f1f au/waa-ljayk8 occur at ordinary speeds, say $90 \, \text{km/h}$?

Suppose the speed of light were infinite.geid /r,e0y0k7f:s2ikh7z jz d6 1lst What would happen to the relativistic predictions of length contractionz7 0,f26ik7iygkrs/dst:led j e 0h1z and time dilation?

Discuss how our everyday lives wou5m:+ /fghrpd w1tugb;ld be different if the speed of light were onlyhgf/ ;5drm 1+wu:bpgt $25 \, \text{m/s}$.

Explain how the length contraction and time dilation formulas hm:2m6hu ce70goh* fvmight be used to indicate that c is the limiting speeoehmuh0mv2f *7c:g6h d in the universe.

The drawing at the start of this Chapter shows the4b rq7mb zkobi3u+9h5 street as seen by Mr Tompkins, for whom the qizoh+b9 bum7r5bk34speed 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 tnk +j uyk)qqo*f(es(sp2bt:-o travel at speeds less than c. Does this put an upper limit on the momentum of an electron? If so, what is this upper limit? If not, explaink so qky +pn2se* f-b)(jq:t(u. ----待选择----yesno 

  Can a particle of nonzero rest mass attain the speedp.4 c8 nkspg8p 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, does this meevab 6/4 q5kosan that a spring has more mass when com6e skq5ob v/4apressed than when relaxed? ----待选择----yesno 

It is not correct to say thvtu3 f*;ibs/dat "matter can neither be created nor destroyed." What must we say i;f*u/dv bs 3tinstead?

  Is our intuitive notion that velocities simply add, as we did in Section 3m,l.ih7 s :sem 6tmy3fw movio228 3is–8, completetmo2mi 27eo 6,3sm8i .iywsm3shfvl :ly wrong? ----待选择----yesno 

  A spaceship passes you at a speed of 0.750c. You meas(w.)igei4m 0q) b/p(sfkwwub l (t /tnure its length to be 28.2 m. How long would it be when at rest i /fimwb )luw(b0sqgp( /e(.kntw4)t? $L_0$ =    m

  A certain type of elementary particle nznv xu-m(fj h*/( 2 v+5quphhtravels 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 intervaljb ts mq(nft(( h:i )kf*cq7v.s depend on the 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 stgk2 vpy5 s 2 c), dv7u4fdjebgmwf*/5sar 125 light-years from Earth at a 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 ocj/k qphi s*3d6a((x aj pg9kbzhtv/o 1957rlifetime 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 82g /bc: /90yjlczgi1t h light-years away. How fast would you have to travel so that to you the distab/zh:tg icc/09jg 1ylnce would be only 35 light-years? v =    c

  Suppose you decide to travel to a star 85 light-years away at a speed that:tmf0 p 9) fu,9qvatol tells you the distance is only 25 light-years. How many years would it take you to make the trip ,)fo: ufvl0aq99ttpm ? 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 ) idf atq )rt 6n ph9:5)t5af-dskm5cwEarth 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 starship Enterprise had just returned from a nox/2+.kb e oifqwh6b:c3 mrt.o(0og5-year voyage whilef 0m+g(/oocb bh6.3kw:i tqx 2oe.n ro 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-yearswh ily x.-d9xv6 xh39k away. How long would it take a spacecraft traveling 0.960c hldh 9.6wxi3x 9- vkxyto 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" swmixu; uwn,90 2j 6zlppacecraft at a speed of 0.660c. It is measured in your frame to be 4.80 m long and 1 6zmj;u92lpxw,u n0 wi.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 travdg()93vzwicm6 y9dx h el 15 m before it decays? The average lifetime, at resh9zv6 3m xwdc d9)giy(t, is $2.6 \times 10^{-8} \, \text{s}$. v =    c

  What is the momentum of a proton travelingr.w:rr)5ni 6ofj v smd;zs 7wy(z9,gw at $v =0.85c$? p =    $ \times 10^{-19} \, \text{kg·m/s}$

  At what speed will an object’s relata3 74j ar)7ry*vgeqtv ivistic mass be twice its rest mass? v =    c

  A particle of rest mass ,mhz5g)dt 3ea$m_0$ travels at a speed $v =0.20c$. At what speed will its momentum be doubled? v =    c

  (a) A particle travels at k5k9zts+ svz6d5p (pj5 5wmps $v =0.10c$. 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 momentum o 7,+;th:a,yyj z ni-mjy(highf a proton that accelerates
(a) from 0.45c to 0.90c,    %
(b) from 0.90c to 0.98c?   %

  A certain chemical r3)ry9 adwa r*lh93ql seaction 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 breakse4tw:1x vqizb8 f)ir4 apart in the process known as fission in a nuclear reactor, the riw4:vtzx4 81qeb f )iresulting fragments have a total kinetic energy of about 200 MeV. How much mass was lost in the process? $\bigtriangleup m$ =    $ \times 10^{-28} \, \text{kg}$

  Calculate the rest energy of an elecsln. ah;xr bxv2,txkt2 r9r:1tron 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 pr4swd c /so1e/l c*o bvdf1b9)(muw-b moton in $\text{MeV}/c^2$. $m_0$ =    Mev/$c^2$

  The total annual energy consumption in the Uni luvjo0mf3k .5ted 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 frn q/r3v poex 9,;ya(dmom conversion of 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 particle when its kinetic energy equals its resthn,,n vc;xgut;n6 2l znvtadxkw )5)) energy? v vncug,,l; )2xk n6 azdtvnx ; )wht5)n=    c

  At what speed will an object's ki.ukcb.0k (m ixqew)na m.2 hn.netic energy be 25% of its rest energy? v =    c

  (a) How much work is required to accelerate a proton from re*yjxl,ls( 6)bifgsek(o6 4tmst up to a speed of 0.997c? kfeysm4sxo,l( (b)6j g*il6t 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 of a proton trayx6jaol+cfmcb yc*-6 q3 k +5kr *k*fzveling $2.60 \times 10^8 \, \text{m/s}$.
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, its kinetic energy is 750 MeVtwy a759y0 m;;i wcrf)ii t3s-u dl0pd)-0m;wil) 7;5dyu3i0pcti s tw9y rfad?    $\times 10^{-19} \, \text{kg·m/s}$

  What is the speed of a proton accelerated su4ba0+i)nqtbzy ,u)by a potential difference of 105 MV? v4y)an)quz0b s +, tbui =    c

  What is the speed of an electron whose kinetic energy isjny v,hin18 c0 1.00 MeV? v =    c

  What is the speed of an electron just be7k4 + ng:tfsbbfore it hits a television screen after being accelerated from rest by the 25,0kf bb+:s4tg 7n00 V of the picture tube? v =    c

Two identical particles olco. xx:ph9+of rest 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 of a protas)n7ys+eh;w x q0 mpxoy,4 6uon ($m_0 =1.67 \times 10^{-27} \, \text{kg}$) whose kinetic energy is exactly half
(a) its total energy, v =    c
(b) its rest energy.v =    c

  What is the speed and the moment8nstl2 z/x 0vm 2;qmthum 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 is accelerated t 6 tab60cr g4u.vcgv-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 moaa;(o jr 67 vkejl(e*fjal ;2vmentum 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 nucleus;6hrpi.( fy 3k rjph0zx 0ktr4, $^{241}\text{Am}$, 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 particle l.2c,/fe o:jym5y ttyxxq0,iof nonzero tfm,x:yy2ox ei0.tycq ,/lj 5rest mass, and (b) a particle with zero rest mass.

  What magnetic field intensity is needed to keep 998-GeV protons revolvi3rlf6x8d 0hhn ng in a circle of radius 1.0 km (at, say, the Fel3 dr86xfh0 hnrmilab synchrotron)? 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 respeecu46,mmer uja110j fct to the Earth) observes a meteor come from behind and pass her at a speed she mea1 r6m4j0 1uum e,ajcfesures as 0.50c. How fast is the meteor moving with respect to the Earth? u =    c

  Two spaceships leave Earth i0bp.9ifx c84 lud5ykue2xv m.n opposite directions, each with a speed of 0.50c with respect to Earth. ubid mcvp 4 . .9285x0yulfxek
(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 at 0.71c. A secondmly 9arr+f;lc0ju* c6 spaceship leaves the first at a speed of 0.87c with respect to the first. Calrc*u6a;+jfyl0c9lm rculate 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 vessel approac-h v mxc.v gww3g1v* lm)of1,gh at a speed of 0.60c. The Enterprise comes to the rescue (Fig. Below), overtaking the aliens whil)m1v.cfv3o-*hg,xw g vg m1wle 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 two escape pods in09lt v qf8s3y mg+tzzr3df1*a opposite directions. One travels at *ylt138 tq93fdv g 0fz+marzsa 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. Atkc7 1qg0mmzz/ the same time, rocket B passes Earth moving 0.95c relative to Earth in the same direction. How fast is B moving relative to A k1z0z/qgmcm7 when it passes A? u' =    c

  The nearest star to Earth is Proxima1k c:buua0vy2 hxbqp/;f 4 ay, Centauri, 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+rf t c9/0ethrm 6n4xyegp 3;d traveling faster than about 0.1c is called relativistic - i.e., for which the correction using special relativity is a significant effect. Determine the speed of an electron n;dtrycrfm 04h36t +e9/ge pxin 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 mkidr 7)a/k fmek3i-8 m e7c0g$v$ 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 to be totally deff-x)4 ak0 btw ,cs+ z/usq:xgstroyed to run a 100-W lightbulb for 1 year?4f0suxwxa,+ b c:-ts/ qf)z gk $m_0$ =    $ \times 10^{-8} \, \text{kg}$

  What minimum amount of electromagnetic energy is needed to produce an electronxjo 0 0),hbvee and a positron together? A positron is a particle with the same rest mass as an electron, but has the opposite charge. (Note that oje0bhvx, e0 )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 o x*-xi9y7dpi at 33% the speed of light collides head on with a positive muon traveling at 50% the xd97i-yipo*xspeed 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 6n*7cqdrx zu3/ omck) into a proton, an electron, and a neutrino. Assume the neutrino's rest mass is zero, and the other mass 3c m*c7 qunko/dxz)6res can be found in the Table inside the front cover. Determine the total kinetic energy shared among the three particles when a neutron decays at rest. KE =    MeV

  The Sun radiates energy at 0f8hifkd5s/j+ vf +dho.2llja rate of 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 negative charge and a spe)o8d srt+ r/kmucz44k thny96ed 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 hf-1h8t.ih 4ju xg (.(+cx cdbbqu dq.eelium nucleus into its constituents, two protons and two neutrons? +(bqh d.-t 4.hf bc xq.(gd1 xcujuei8The 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 the total binding energy of the $^4\text{He}$ nucleus.) KE =    MeV

  What is the percentage increase in the (relativistic) mass of a car ))8b eepkfggbut; .v5 traveling 110 km/h as compared to at rest? [Hint: use tvggf)b p);u8.bt 5eekhe binomial expansion.]$\frac{\left(m-m_0\right)}{m_0}$ =    $\times 10^{-11}\%$

  Two protons, each having a speed of 0.935c in the0*has2vj-jgn* b q5ke laboratory, are moving toward eacv*ejqsng 205abk*j - hh other. 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 partic*nj**d pmwj3zle with momentum $p$ and energy $E$ has a speed given by $v = \frac{pc^2}{E}$.

  The fictional starship Enterprise obtains ita7y+5 csb+ gsiu mv2.cs power by combining matter and antimatter, achieving comsy +c 52acm7ubsvi+.gplete 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 6 d36a qxvqe4kis greater than its rest massvk4ad6q6x3eq $m_0c^2$ 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-mv5p 6jti32o nh7p9irn-long pole into a 12.0-m-long barn if he runs fastopin2 6nti3 7pv5r9hj 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 moles ofb,jj*c) vo/3 xz:e sd;6yuvbi water, the energy released is 484 kJ. How mued,szjyb)*6b/; 3ovvu:c jixch does 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 j6 +n*twdt,bqtwo identical 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? u6q,tbn *+wtdj =    c

  An astronaut on a space)l / sv9oypl7 0)esqclib s*t3ship traveling at 0.75c relative to Earth measures his ship to be 25 m ly)9st7v/bspsl0l)e*q3i colong. 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 azutm:i omb)(0t a speed of 0.85c away from Earth. You send a laser beam toward the Earth traveling at velocity c relative to you. What do observers on the Earth (z om)ib utm:0measure for the speed of the laser beam?

  A spaceship and its occupants have a total mass of 150,000 kg.bl u,ai:b-ogz5/ b 0lxg;:ktb, reo.o The occupants would like to travel to a star that is 25 light-years gag,:k, /t .ebiro 5boo -xz;0l :lbbuaway 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 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 left Earth at a speed of 0.99c. b(goo1s wnk z:z+) fs2What is the spaceship's kinetic energy? Compare with the total U.S. annual nz:kz2f+ s1w(sog bo)energy consumption (about $10^{19} \, \text{J}$). KE =    $ \times 10^{20} \, \text{J}$

  A 42,000-kg spaceship is to travel to thq9- nu, xdrswx37ni 4te vicinity of a star 6.0 light-years from Earth. Passengers on the ship want the (one-way) trip to take no more than 1.0 year. How much work must be doxit 9u,d-q nnw4x rs73ne on the spaceship to bring it to the speed necessary for this trip? u =    c

  A 1.68-kg mass oscilla3dz sp,p; 8sbhtes on the end of a spring whose spring stiffness constant ipzps;db hs,83s $k=48.7 \, \text{N/m}$. 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 mavbdo dgdr)p6h0;(pn2 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 $KE_\mu = \frac{(m_\pi - m_\mu)^2 c^2}{2m_\pi}$.