A train moves past a telegraph post and a bri | vedclass

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

Question

(D) Let the speed of the train be $v \; m/s$ and the length of the train be $L \; m$.When the train passes a telegraph post,it covers its own length i

Vedclass · Accepted Answer

$79.2$

Vedclass · Answer

(D) Let the speed of the train be $v \; m/s$ and the length of the train be $L \; m$.When the train passes a telegraph post,it covers its own length in $8 \; seconds$:$L = v 	imes 8 \quad ... (1)$When the train passes a bridge of length $264 \; m$,it covers its own length plus the bridge length in $20 \; seconds$:$L + 264 = v 	imes 20 \quad ... (2)$Subtracting equation $(1)$ from equation $(2)$:$(L + 264) - L = 20v - 8v$$264 = 12v$$v = \frac{264}{12} = 22 \; m/s$To convert the speed from $m/s$ to $km/hr$,multiply by $\frac{18}{5}$:$v = 22 	imes \frac{18}{5} = \frac{396}{5} = 79.2 \; km/hr$.

$A$ train moves past a telegraph post and a bridge $264 \; m$ long in $8 \; seconds$ and $20 \; seconds$ respectively. What is the speed of the train (in $km/hr$)?

Similar Questions

$A$ train $800 \; m$ long is running at a speed of $78 \; km/hr$. If it crosses a tunnel in $1 \; minute$,then the length (in $m$) of the tunnel is:

$A$ train $100 \; m$ long is running at the speed of $30 \; km/hr$. Find the time (in $sec$) taken by it to pass a man standing near the railway line.

Two stations $P$ and $Q$ are $110 \; km$ apart on a straight line. One train starts from $P$ at $7 \; am$ and travels towards $Q$ at $20 \; km/h$ speed. Another train starts from $Q$ at $8 \; am$ and travels towards $P$ at a speed of $25 \; km/h$. At what time will they meet?

$A$ train passes a station platform in $36 \; \text{seconds}$ and a man standing on the platform in $20 \; \text{seconds}$. If the speed of the train is $54 \; \text{km/hr}$, what is the length (in $m$) of the platform?

In what time (in $sec$) will a train $100 \; m$ long cross an electric pole,if its speed is $144 \; km/hr$?

Vedclass Test Series

Exam Paper Generator

Online Exam Module