Question

Q.10) A train travelling at v54km/hr and cross a pole in 12 sec,what is the length of train?​

Answer 1

Answer:

• The length of train is 180 m.

Step-by-step explanation:

Given that:

• A train travelling at a speed of 54 km/hr and cross a pole in 12 sec.

To Find:

• What is the length of train?

Converting the speed of train in m/sec:

• 1 km/hr = 5/18 m/sec
• 54 km/hr = (54 × 5)/18 m/sec
• 54 km/hr = 15 m/sec

Finding the length of train:

We know that.

• Length of train = Speed × Time

We have.

• Speed = 15 m/sec
• Time = 12 sec

⟶ Length of train = 15 × 12

⟶ Length of train = 180

∴ The length of train = 180 m.

Answer 2

${\large{\pmb{\sf{\bigstar \:{\underline{Understanding \: the \: Question...}}}}}}$

★ This question says that we have to find out the length of the train which is travelling at velocity/speed of 54 kilometres per hour and it is crossing a pole in 12 seconds. Let us solve this question properly!

${\large{\pmb{\sf{\bigstar \:{\underline{Given \: that...}}}}}}$

★ Velocity of the train = 53 km/h

★ In 12 second it cross pole.

${\large{\pmb{\sf{\bigstar \:{\underline{To \; find...}}}}}}$

★ Length of the train

${\large{\pmb{\sf{\bigstar \:{\underline{Solution...}}}}}}$

★ Length of the train = 180 m

${\large{\pmb{\sf{\bigstar \:{\underline{Using \; concepts...}}}}}}$

★ Formula to find out the length of the train.

★ Formula to change km/h into m/s

${\large{\pmb{\sf{\bigstar \:{\underline{Using \; formulas...}}}}}}$

${\small{\underline{\boxed{\sf{\bull 1 \: km/h \: = 5/18 \: m/s}}}}}$

${\small{\underline{\boxed{\sf{\bull Length \: of \: train \: = Speed \times Time}}}}}$

${\large{\pmb{\sf{\bigstar \:{\underline{Full \; Solution...}}}}}}$

~ Firstly let us use the given formula and let's convert km/h into m/s

${\small{\underline{\boxed{\sf{\bull 1 \: km/h \: = 5/18 \: m/s}}}}} \\ \\ :\implies \sf 1 \: km/h \: = 5/18 \: m/s \\ \\ :\implies \sf 54 \: km/h \: = \dfrac{5}{18} \times 54 \\ \\ :\implies \sf 54 \: km/h \: = 5 \times 3 \\ \\ :\implies \sf 54 \: km/h \: = 15 \: m/s$

${\underline{\frak{15 \: m/s \: is \: velocity \: of \: train}}}$

~ Now by using the given formula let us find the length of the train.

${\small{\underline{\boxed{\sf{\bull Length \: of \: train \: = Speed \times Time}}}}} \\ \\ :\implies \sf Length \: of \: train \: = Speed \times Time \\ \\ :\implies \sf Length \: of \: train = 15 \times 12 \\ \\ :\implies \sf Length \: of \: train = 180 \: m$

${\underline{\frak{180 \: m \: is \: the \: length \: of \: train}}}$