You are in a windowless car in an exceptionally smooth train movingwuh+b1:f 6u sjp2bh 7d at constant velocity. Is there any physical experiment you can do in tu wf:hb7+pdh2s6j ub1he train car to determine whether you are moving? Explain. ----待选择----yesno 

You might have had the experiencer9 /i,w,h)2e88bzlbuahsf a .j c ah/h of being at a red light when, out of the corner of your eye, you see the car beside you creep forwarj8)wa a 9/fbrh,h2 hi.zhlc 8es/b a,ud. 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 ofhy,m*ff)bje803 n -fx *chqmb a moving railroad car, and throws a heavy ball straight up (from his point of view). Ignoring air resistance, will the ball land on the car f 8m cqhe)3*nbf*hxy-f 0 jbm,or behind it?

Does the Earth really go around the Sun? Or is it also valid to say that the Sqm7)wd +qy 7pwun goes around the Earth? Discuss ipq+ 7qdmy) 7wwn view of the first principle of relativity (that there is no best reference frame). Explain.

If you were on a spaceship traveling at 0.5c away fr ezdomk/5hfn.txe ,p h/n4.;v om a star, at what speed would the /k.pvf; 5nt4em e zh.n ,hod/xstarlight pass you?

The time dilation effect is sometimes expressed as 7wqgogqw10n - “moving clocks run slowly.” Actually, this efqw0onq w1g -7gfect has nothing to do with motion affecting the functioning of clocks. What then does it deal with?

Does time dilation mean that time actually passes more slowly in moving rhi ggsi1, .,ugeference fram.igus, ig h,g1es or that it only seems to pass more slowly?

A young-looking woman astronaut has just arrived home from a long trip. She rxo6n*jk o ;ko5ushes up to an old gray-haired man and in the ensuing conversation refers to him as her son. How might to5j ;6kon*kxo his be possible?

If you were traveling away q5h. p9pmo ds3 lfxf*9k7d*ia 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 tdfol *iapk7pqm* xd. 5f93s9helescopes say about you?

Do time dilation and length contraction occur at ordinary speeds, saq3)n1 kxd3btub d-b/ fy $90 \, \text{km/h}$?

Suppose the speed of light were infinite. .ruz0u 8sj,f kqj(n)aWhat would happen to the relativistic predictions of fjkaqu)(j 0,r8n.szu length contraction and time dilation?

Discuss how our everyday lives would be different if the speed o lzf a;h5t(c6gqj7e 3jf light were only tczg 3(7;hljqf 6 ja5e$25 \, \text{m/s}$.

Explain how the length contt 2dgk yc i-t ;,8*ppkpqsu3f0iu3w l6raction and time dilation formulas might be used to indis36kgp k-fp;p *ci83u lwyt tdu2 ,0qicate that c is the limiting speed in the universe.

The drawing at the start of this Chapter shows the street as seen by Mr x7nl- 92 oeyq40coc/gqnp.j tTompkins, for gyl.ejo tpn/x o2-nq7ccq940whom 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 spee4a*fq-dld1 kdvu1 , xeds less than c. Does this put an upper limit on the momentum of an equ41d,alvx kfe*d1d- lectron? If so, what is this upper limit? If not, explain. ----待选择----yesno 

  Can a particle of nonzero rest mass attain the speedj u,zkikff.+/ 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 thy+qw7g ,m/ -zfca d0obis mean that a spring has more mass when compre wgzo7yq+/ a,-cfd0mb ssed than when relaxed? ----待选择----yesno 

It is not correct to say that "matter can neither be create.u luo7 sy5+ xjnvp)f1d nor destroyed." What must weo ns).u lju5p7fy1v+x say instead?

  Is our intuitive notion that velocities g h2cm(.v5vb jsbl s1:simply add, as we did in Section 3–8, co (v:.sjs12mh5g vbc blmpletely wrong? ----待选择----yesno 

  A spaceship passes you at a speed of 0.750c. You measure its lenj2vfila n u bm.9b*+aj jh60e+gth to be 28.2 m. How long would j v0m n i*b+b+ lhjfu26aa.ej9it be when at rest? $L_0$ =    m

  A certain type of elementary particle travels at ujk-* (vm-y(s9eebvha 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 fact hnoy (f6*n7ywor $\beta = \frac{1}{\sqrt{1 - v^2/c^2}}$ 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-yea g6 ; -rcm+o;zs6xpccjrs 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-6j9 cus8jyzw,4vvq )*n x ha*wv* ykm average lifetime 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 st196fya y+vwef ar is 82 light-years away. How fast would you have to travel so that to you the distance would be on+1vwf6ae9f yyly 35 light-years? v =    c

  Suppose you decide to traveltaaz d*u/u9pp4:s w;xm,gjm4 to a star 85 light-years away at a speed that tells you the distance is only 25 light-years. How many years would it take ymw9pstm4u,a j4;u*dg: pz/xaou 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 i-cn;z j8bsln* s $11.2 \times 10^3 \, \text{m/s}$. 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 s5( m6heoy/ fjrtarship Enterprise had just returned from a 5-year voyage whiyemo rj f/h65(le 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. How long would it take -w2/s w/io*hcwz5 ah na spacecraft traveling 0.960c to rezoi/hhwa 52/-*cs w wnach 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" spaabvk2 u) 4m;fng 1te,/ x:j+qh-whrcdcecraft at a speed of 0.660c. It is measured in your frame to be 4.80 m long and 1.25 t : - 2g/e,+hkbj;a)4vf dhuxr c1wnmqm 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? The39xto 7a5grmt +nqqm( average lifetimg3qt (mmq7a5 +xrnto9 e, at rest, is $2.6 \times 10^{-8} \, \text{s}$. v =    c

  What is the momentum of a proton travelwh ; -c4y h,mlr:5wll,q)vmqwing at $v =0.85c$? p =    $ \times 10^{-19} \, \text{kg·m/s}$

  At what speed will an object’s relativistic mass be twice is(bp8qkj7k(sw 0zwj f0n45 gzts rest mass? v =    c

  A particle of rest mass xyci -)/1cyofugpwhqbh .--6 $m_0$ travels at a speed $v =0.20c$. At what speed will its momentum be doubled? v =    c

  (a) A particle travels at v-4oz uqilkb5 */ch(t $v =0.10c$. 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 of a proton cy9o;-q4p3ynh0krw v that accelerates
(a) from 0.45c to 0.90c,    %
(b) from 0.90c to 0.98c?   %

  A certain chemical reaction(fzda; 3ak l i ll00f0mc*dpz8 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 known as fisn9. 8e*qrz0l(dkmet- ugn qi.sion in a n*kmq.-90.n( gezqled8 t nuiruclear reactor, the resulting 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 electron in joules an f1r 9vs gqhbh8:(v9 hqmfh: )6jov5xyd 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 fadk.ch51zeityu b*8bc;b9; of a proton in $\text{MeV}/c^2$. $m_0$ =    Mev/$c^2$

  The total annual energy consumption in the United States is aboutuoh*4; /:kooii nfqd2 $10^{19} \, \text{J}$. 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 3 r8eho7dx/rjtq/8xc 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 i*b--of g6psvvo( 3 up4c5ynrj ts rest energy? v = o n6ov rcf-gspj3vy4p(b*-u5   c

  At what speed will an object's kinetic energy be 25% of its rest energy? v z wju7fhsba9kx2z -f7f/ ks, j 3*e11pn, mxvi=    c

  (a) How much work is required to acceleratend um -b(yzjeu ,aw-*7 a proton from rest up to a speed of 0.997c? W = u,ym*n7zbd( we- -jau   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 travx z4.u1xe9, ccim u0hveling $2.60 \times 10^8 \, \text{m/s}$.
KE =    $ \times 10^{-10} \, \text{J}$
p =    $ \times 10^{-18} \, \text{kg·m/s}$

  What is the momentum of a 750-MeV proton xygpapm:- mhroz.ja: du( 7*6 (that is, its kinetic energy is 750 MeV)*.z 6dx: ymp7mpughr: ao(a- j?    $\times 10^{-19} \, \text{kg·m/s}$

  What is the speed of a proton accelerated by a pogk r3.zw55f aztential difference of 105 MV? v z gzr5wfa.k53 =    c

  What is the speed of an electronu5 aaylo1ru -9.rcp7* g(fx no whose kinetic energy is 1.00 MeV? v =    c

  What is the speed of an electron juwme3k tdfc62 m:g -lnyj+eqm je665y+st before it hits a television screen after beinmy 5mkn+qm+eledf3jytc -w:6626 jg eg accelerated from rest by the 25,000 V of the picture tube? v =    c

Two identical particles of rest massc.n0sre. * *o5(cn4zamg am nm $m_0$ 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 proton.hf1znp pgq h84) h2dw 4zci:ic.w 1yv ($m_0 =1.67 \times 10^{-27} \, \text{kg}$) 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 electrze td(rp(;td+on ($m=9.11 \times 10^{-31} \, \text{kg}$) whose kinetic energy equals its rest energy?
v =    c
p =    $ \times 10^{-22} \, \text{kg·m/s}$

  Suppose a spacecraft oqxe ea40tdj4 :f mass 27,000 kg 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 eyxo+m5c i471 hg+x1c c:aferxrf + 8gdnergy 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 nucleus, oa(hrk8dt3d*ys3l 9o$^{241}\text{Am}$, 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 of nonzxxbpc s 06l98aero rest mas9xbslc6p8 x a0s, and (b) a particle with zero rest mass.

  What magnetic field intensity 5z +eu rye+be:is needed to keep 998-GeV protons revolving in a cir eue:eb+yr5+ zcle of radius 1.0 km (at, say, the Fermilab 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 0pzf:.i,j ja(o.50c (with respect to the Earth) observes a meteor come from behiz,o . p(jafij:nd 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 wiq en,mkw3 k v7xxspz06w)vp,2c-l2u c th a speed of 0.50c wi,sl vue pkp7k ,6z)-32qwvxx n2c 0cmwth 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 at 0.71c. A second s 4q4sxfj)k*ho q)pu:nji /(pbpaceship leaves the first at a speed of 0.87c with respect to the first. Calculate the speed (q: ikp 4j*n uh4fo)s/ xqjpb)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 approach at a speed ofg2kkf8.i.7s a oyro3g 0.60c. The Enterprise comes to the rescue (Fig. Below), overtaking the aliens while moving directly toward Earth at a speed of 0.90c relative tgof. 7 o sai2gk8yr3k.o 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 in opposite dire 0x5v:kxvsfjr 7a0 rvi725rvzctions. One trai5x2:kr5f a07s 0jvv v7rzrvxvels 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.a6xf q;ng (f ;)hrku uh.qf51u At the same time, rocket B passes Earth moving 0.95c relative to Earth in the same direction. )nq h kf1;f(rfax uqu;.hgu65How fast is B moving relative to A when it passes A? u' =    c

  The nearest star to Earth is Proxima Centauri, 4.3 light-years fqc enm3-hel-t( 4 -yhaway.
(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 than about 0m8qmesa6 2yz -.1c is called relativistic - i.e., for which the correction using special relativity is a significant effect. Determine the speed of an electas2ymq 6-8ezmron 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 speedxrp tbnf6:5 gzg9(ec6 $v$ 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.xc 1mxl rgph99n;z.j be totally destroyed to run a 100-W lightxl hjgmz ..r19p x9cn;bulb for 1 year? $m_0$ =    $ \times 10^{-8} \, \text{kg}$

  What minimum amount of electwjix6 //j 3mvghuh .1kny 0pj9romagnetic energy is needed to produce an electron and a positron together? A positron is a particle with the same y/iv6 njj 3kh xg0mhwp.ju/91rest mass as an electron, 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 sx0il;m7;hgg q;fw+ nqd4w8d xpeed of light collides head on with a positive muon tgd+hqd70mxwfqxwinl;4 ; ; 8g raveling at 50% the speed 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, an electron, and a neutrino. Assu87xw rkbbi(gu(,hj-m;i zp k 4me the neutrino's rest mass is zero, and the other masse8zmp-kj4 b x7i( ugribwh;k(,s 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 energyt (z60ef p w9hi+vj-vkctt8pp4z96 ju at a 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 chr9/b4bz*:kp7 rpsw y carge 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 heyj 7nha9 w;pos(.do+ ylium nucleus into its constituents, two protons and two neutrons? The rest masses of a proton (including an electron), a neutron, and helium are, re h7ao jpo+9s;yyw( .ndspectively, 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 (reh; xafr846o mqlativistic) mass of a car traveling 110 km/h as compared to x6;raf4 8mqo hat 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 in the laboratory, are moving towardqf 2) f 6n); x28gqmxydo clhnz-).ekd each other. D)2dy o) 8;xfkm6nc. q-x2) zehfdqglnetermine
(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 momenturn) i; 3ztplsgidi8p8c*n *v /m $p$ and energy $E$ has a speed given by $v = \frac{pc^2}{E}$.

  The fictional starship Enterprise obtains its power by combining matter anuz 419)tg eg *ifhth8sd antimatter, achieving complete conversion of mass into energy. If the mass of the Enterprise is approximately u9egsht 84*g 1it zh)f$5 \times 10^9 \, \text{kg}$, 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.l i*ycrl/xqt 4s8md zli; ii9zon)40 its kinetic energy is greater than its rest ma/8;c 9. *t i isx mi4lzl04qi)loyndzrss $m_0c^2$ 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-m-long pole int b4zx1 hbt*yv eo;.lbh-89p2zwdmi :l o a 12.0-m-long barn ifpyb-d hzo1*ltw9hlb8b ;:.vmi x42ez 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 forthq q810jmf 4e0k upb58uwmc 5+p0 z5kavgc6 rm two moles of water, the energy released is 484 kJ. u re5k10bc m+0 wzj60pkc5ghq pfu5vqa 48m8tHow much 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 two identical parti;6vni-fsu cm .cles are created, traveling in opposite directions. If the speed of ea. misuc6fv;- nch 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 spaesvv,1e 2z f0 q31w(p*z tcexeceship traveling at 0.75c relative to Earth measures his ship to be 25 m long. On the ship, he eats h ( 3c02zeez1v*se,e1fpv xqw tis 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 spaceshiq5x:vs8pgfr. u w 3ie,p at a speed of 0.85c away from Earth. You send a laser v3wu:.,rgi5f8ps exq beam toward the Earth traveling at velocity c relative to you. What do observers on the Earth measure for the speed of the laser beam?

  A spaceship and its occupants have a total mass of 150,000 kg. Thuc9lo mf57zu +e 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 +9fm 75lucz uoto 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 space6nyjnr6bbdqhv *1 p 6i3 k2o9jship left Earth at a speed of 0.99c. What is the spaceship's kinetic energy? Compare with the toj6biq2 3 bkyjvdo *1ph6rn 9n6tal 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 6.0 fsnpc)ljrc(8ue.8 3 -vval4 tq)g8pn light-years from Earth. Passengers on the ship want the (one-way) tripq-narv8. nvue()4p3lclf c8s jg) p8 t 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 on v*v9 bwdu7s3w the end of a spring whose spring stiffness constant7u*wvw93 dvs b 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 mas8 p-dxdex:1ob0;sr gijm 0ab.s $m_\pi$ 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 $KE_\mu = \frac{(m_\pi - m_\mu)^2 c^2}{2m_\pi}$.