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properHoc

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Key 6

Up a level : Adding velocities
  1.  Forward moving:
    \displaystyle w=\frac{{u+v}}{{1+\frac{{uv}}{{{{c}^{2}}}}}}=\frac{{0.7c+0.8c}}{{1+\frac{{0.8c\cdot 0.7c}}{{{{c}^{2}}}}}}=\frac{{0.7+0.8}}{{1+0.8\cdot 0.7}}c=0.9615c
    Moving toward the back:
    \displaystyle w=\frac{{u+v}}{{1+\frac{{uv}}{{{{c}^{2}}}}}}=\frac{{-0.7c+0.8c}}{{1-\frac{{0.8c\cdot 0.7c}}{{{{c}^{2}}}}}}=\frac{{-0.7+0.8}}{{1-0.8\cdot 0.7}}c=0.2272c
  2. \displaystyle w=\frac{{c+c}}{{1+\frac{{c\cdot c}}{{{{c}^{2}}}}}}=\frac{{2c}}{2}=c
Up a level : Adding velocitiesLast modified: Jun 10, 2025 @ 15:51
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