I'm in frame $S$, and you are in is in Frame $S'$, which moves with speed $V$ in the $+x$ direction. An object moves in the $S'$ frame in the $+x$ direction with speed $v'_x$. Do I measure its $x$ component of velocity to be $v_x = v'_x$? 1. Yes 2. No 3. ??? Note: * Correct Answer: B

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I'm in frame $S$, and you are in is in Frame $S'$, which moves with speed $V$ in the $+x$ direction. An object moves in the $S'$ frame in the $+y$ direction with speed $v'_y$. Do I measure its $y$ component of velocity to be $v_y = v'_y$? 1. Yes 2. No 3. ??? Note: * Correct Answer: B

With Einstein's velocity addition rule, $$u = \dfrac{u' + v}{1+\frac{u'v}{c^2}}$$ what happens when $v$ is very small compared to $c$? 1. $u\rightarrow 0$ 2. $u\rightarrow c$ 3. $u\rightarrow \infty$ 4. $u \approx u' + v$ 5. Something else Note: * Correct Answer: D

With Einstein's velocity addition rule, $$u = \dfrac{u' + v}{1+\frac{u'v}{c^2}}$$ what happens when $u'$ is $c$? 1. $u\rightarrow 0$ 2. $u\rightarrow c$ 3. $u\rightarrow \infty$ 4. $u \approx u' + v$ 5. Something else Note: * Correct Answer: B

With Einstein's velocity addition rule, $$u = \dfrac{u' + v}{1+\frac{u'v}{c^2}}$$ what happens when $v$ is $c$? 1. $u\rightarrow 0$ 2. $u\rightarrow c$ 3. $u\rightarrow \infty$ 4. $u \approx u' + v$ 5. Something else Note: * Correct Answer: B