SSC GD Constable 4 Feb 2025 Shift 2 Paper

Relative speed when two objects move towards each other $=$ Speed of first object + Speed of second object Time taken to cross each other $=$ Total distance $∕$ Relative speed
Calculation:
Relative speed $=50\mathit{k}\mathit{m}∕\mathit{h}\mathit{r}+70\mathit{k}\mathit{m}∕\mathit{h}\mathit{r}$
⇒ Relative speed $=120\mathit{k}\mathit{m}∕\mathit{h}\mathit{r}$
Convert speed to $\mathit{m}∕\mathit{s}$ :
$\Rightarrow 120\mathit{k}\mathit{m}∕\mathit{h}\mathit{r}=120\times \left(1000∕3600\right)\mathit{m}∕\mathit{s}$
$\Rightarrow 120\mathit{k}\mathit{m}∕\mathit{h}\mathit{r}=33.33\mathit{m}∕\mathit{s}$
Total distance $=$ Length of first train + Length of second train
⇒ Total distance $=180\mathit{m}+180\mathit{m}$
⇒ Total distance $=360\mathit{m}$
Time taken to cross each other $=$ Total distance $∕$ Relative speed
⇒ Time taken $=360\mathit{m}∕33.33\mathit{m}∕\mathit{s}$
⇒ Time taken $=10.8$ seconds