H.W. 01 관련

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1. Q-1.10

Suppose that $A'$, $B'$, and $C'$ are at rest in frame $S'$, which moves with respect to $S$ at speed $v$ in the $+x$ direction. Let $B'$ be located exactly midway between $A'$ and $C'$. At $t'=0$, a light flash occurs at $B'$ and expands outward as a spherical wave.

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2. Q-1.13

Suppose that an event occurs in inertial frame $$S$$ with coordinates $x=75\:m$, $y=18\:m$, $z=4.0\:m$ at $t=2.0\times10^{-5}\:s$. The inertial frame $S'$ moves in the $+x$ direction with $v=0.85c$. The origins of $S$ and $S'$ coincided at $t=t'=0$.

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3. Q-1.20(b)

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4. Q-1.22

A nova is the sudden, brief brightening of a star (see Chapter 13). Suppose Earth astronomers see two novas occur simultaneously, one in the constellation Orion (The Hunter) and the other in the constellation Lyra (The Lyre). Both nova are the same distance from Earth, $2.5 \times10^3\:c\cdot{y}$, and are in exactly opposite directions from Earth. Observers on board an aircraft flying at $1000\:\text{km}/\text{h}$ on a line from Orion toward Lyra see the same novas but note that they are not simultaneous.

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5. Q-1.24

The proper mean lifetime of $\pi$ mesons (pions) is $2.6\times10^{-8}\:\text{s}$. Suppose a beam of such particles has speed $0.9c$.

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6. Q-1.37

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7. Q-1.41

A friend of yours who is the same age as you travels to the star Alpha Centauri, which is $4c\cdot{y}$ away, and returns immediately. She claims that the entire trip took just 6 years.

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8. Q-1.44

A burst of $p+$ mesons (pions) travels down an evacuated beam tube at Fermilab moving at $\beta=0.92$ with respect to the laboratory.

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