Question

A train running at the speed of 60 km/hr crosses a pole in 9 seconds. What is the length of the train?
A.120 metresB.180 metresC.324 metresD.150 metres​

Answer 1

$\blue{\bold{\underline{\underline{Answer:}}}}$

$\green{\tt{\therefore{Length\:of\:train\approx150\:m}}}$

$\orange{\bold{\underline{\underline{Step-by-step\:explanation:}}}}$

$\green{\underline \bold{Given: }} \\ \tt: \implies Speed \: of \: train = 60 \: kmh \\ \\ \tt: \implies Time \: taken \: to \: cross \: pole = 9 \: second \\ \\ \red{\underline \bold{To \: Find: }} \\ \tt: \implies Length \: of \: train = ?$

• According to given question :

$\tt \circ \: Speed = 60 \times \frac{5}{18} = 16.67 \: ms \\ \\ \tt\circ \: Time = 9 \: seconds \\ \\ \bold{As \: we \: know \: that} \\ \tt: \implies Distance =Speed \times Time \\ \\ \tt: \implies Distance = 16.67 \times 9 \\ \\ \green{\tt: \implies Distance \approx150\: m} \\ \\ \green{\tt\therefore Length \: of \: train \: is \: 150 \: m} \\ \\ \blue{\bold{Some \: related \: formula}} \\ \orange{\tt\circ \: v = u + at} \\ \\ \orange{\tt\circ \: s = ut+ \frac{1}{2} a {t}^{2} } \\ \\ \orange{\tt\circ \: {v}^{2} = {u}^{2} + 2as}$

Answer 2

Given Question :-

A train running at the speed of 60 km/hr crosses a pole in 9 seconds. What is the length of the train?

A.120 metres

B.180 metres

C.324 metres

D.150 metres✅

Solution :-

Speed of the running train =60km/hr

Time taken by train =9 seconds

Let the length of the train be x.

As the thickness of the pole is so less that the train crosses it in 9 seconds so it must have just passed the body. Therefore the distance will be equal to the distance travelled by the train.

As we know,

$speed \: = \frac{distance}{time}$

And,

For conversion of km/hr into m/sec, we multiply 5/18.

Therefore,

$60km {hr}^{ - 1} \times \frac{5}{18} = \frac{50}{3} m {s}^{ - 1}$

$x \: = \frac{50 \times 9}{3} = 150m$

Therefore the length of the train is 150 m.