Two trains A and B travel on two parallel rai | vedclass

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(C) Let the total length of the two trains be $L$. Since they are moving in opposite directions, their relative velocity is $v_{rel} = v_1 + v_2$.Give

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(C) Let the total length of the two trains be $L$. Since they are moving in opposite directions, their relative velocity is $v_{rel} = v_1 + v_2$.Given that they take $4 \ s$ to cross each other:$L = (v_1 + v_2) 	imes 4$  --- $(i)$When the speed of train $A$ is increased by $50 \%$, the new speed of train $A$ becomes $v_1' = v_1 + 0.5 v_1 = 1.5 v_1 = \frac{3}{2} v_1$.The new relative velocity is $v_{rel}' = \frac{3}{2} v_1 + v_2$.Given that they take $3 \ s$ to cross each other:$L = (\frac{3}{2} v_1 + v_2) 	imes 3$ --- (ii)Equating $(i)$ and (ii):$4(v_1 + v_2) = 3(\frac{3}{2} v_1 + v_2)$$4 v_1 + 4 v_2 = 4.5 v_1 + 3 v_2$$v_2 = 0.5 v_1$$\frac{v_1}{v_2} = \frac{1}{0.5} = \frac{2}{1}$.

Two trains $A$ and $B$ travel on two parallel rail tracks in opposite directions with speeds $v_1$ and $v_2$, respectively. They take $4 \ s$ to pass each other at these speeds. If the speed of train $A$ is increased by $50 \%$, then they take $3 \ s$ to pass each other. The ratio $v_1 / v_2$ is:

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