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

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(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

Vedclass · Accepted Answer

$2: 1$

Vedclass · Answer

(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:

Similar Questions

Wind is blowing in the north direction at a speed of $2 \, m/s$,which causes the rain to fall at some angle with the vertical. With what velocity should a cyclist drive so that the rain appears vertical to him?

$A$ ship $A$ is moving Westwards with a speed of $10 \, km \, h^{-1}$ and a ship $B$,$100 \, km$ South of $A$,is moving Northwards with a speed of $10 \, km \, h^{-1}$. The time after which the distance between them becomes shortest is ........ $hr$.

When is the relative velocity of two cars moving with unequal velocities less than the individual velocity of either car?

$A$ $150\, m$ long train is moving to the north at a speed of $10\, m/s$. $A$ parrot flying towards the south with a speed of $5\, m/s$ crosses the train. The time taken by the parrot to cross the train would be........$s$.

If a $100 \,m$ long train needs $7.2 \,s$ to cross an object moving in a direction opposite to the train's direction with a speed of $5 \,km/h$, then find the velocity of the train. (in $\,km/h$)

Vedclass Test Series

Exam Paper Generator

Online Exam Module