Rapid Revision for CSIR NET Part A: Formula Sheets on Problem On Train - Check Here!!!

By Astha Singh|Updated : January 27th, 2022

CSIR NET Part-A Formula Sheet: During the preparation, the candidates study different formulas to solve problems, but at the last moment, these formulas might not be remembered by the candidates due to exam fear or pressure. We at BYJU'S Exam Prep do not want our students to lag anywhere during the preparation, so we have come up with a concept of a Formula Sheet that will help them revise the important formulas at the last moment. This formula sheet will be a short revision tool and contain only important formulas that need to be studied at the last minute to boost the score. Our experienced subject-matter experts have meticulously designed this CSIR NET General Aptitude Formula Sheet to provide you with the best authentic material.

In this article, we will cover the CSIR NET General Aptitude Most Important Formulas of Problem On Train. Aspiring candidates can check all the most important formulas of Problem On Train for the last minute revision. Scroll down the full article to find out!

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PROBLEMS ON TRAINS

BASIC CONCEPT

POINTS TO BE REMEMBER

⦁ Time Taken by Train to cross any point, pole, object or a Platform –

This type of question may be asked where the students have to calculate the time taken by a train to cross a point, pole, object Platform or stationary body.
⦁ Time Taken by two trains to cross each other –

In this type of problem, students may be asked to find out the time taken by two trains to cross each other.
⦁ Train Problems based on Equations –

There could be two cases asked where the question and the candidates will have to form equations based on the condition given in the question.

FORMULAS

When a train crosses a single post or pole or man or tree, then the train will move a distance equal to the length of the train.

So time is taken by train to cross =

⦁ When a train crosses a platform or a bridge, the train has to cross the distance equal to the sum of the length of the train and bridge.

So time is taken by train to cross =
⦁ If two trains of length 'x' meters and 'y' meters move in the same direction with speed S1 m/s and S2 m/s resp.

Where S1 > S2 then relative speed = (S1 – S2) m/s and Time is taken by faster

train to cross the slower train =

⦁ If two trains of length 'x' meters and 'y' meters move in opp. direction with speed S1 m/s and S2 m/s resp.

Where S1 > S2 then their relative speed = (S1 + S2) m/s and
Time is taken to cross each other =

⦁ If two trains (or objects) start at the same time from opposite points A and B towards each other and after crossing they take a and b sec in reaching B and A respectively, then: (A's speed) : (B's speed) = ()

EXAMPLE
1. A train is running at a speed of 99 km/h. If the train is 565 m long, then what will be the time (in seconds) taken by it to cross a 975 m long tunnel?
A. 54
B. 40
C. 56
D. 42
Answer-C
Solution-Speed of train = 99 kmph
Length of train = 565 m
Length of tunnel = 975 m

As we know,

According to the question

Hence, Time required by train to cross the tunnel = 56 m

2. If a person travels at a speed of 48 km/h, he will reach his destination on time. He covers two-thirds of his journey in five-sixths of time. At what speed (in km/h) should he travel to cover the remaining distance to reach his destination on time?
A. 96
B. 48
C. 50
D. 100
Answer-A
Solution-
Let the total time taken in journey = x hour
We know that:
Distance = time × speed
= (x) × 48
= 48 km
Now, two thirds of his journey covered by him in five – sixths of time
So, remaining distance to be cover = (48x) ×   = (48x) ×   = 16x
Remaining time = (x) -   =
Therefore, required speed to cover the remaining distance of time =   = 96 km/h

3. Trains A and B of lengths 329 m and 296 m, respectively, are running in opposite directions on parallel tracks, at the speeds of 85 km/h and 65 km/h, respectively. In what time in seconds) will they cross each other?
A. 15
B. 16.5
C. 15.5
D. 14
Answer-A
Solution-
Total distance = 329 + 296 = 625 m
Relative speed = (85+65) km/h = 150 × m/sec = m/sec
Therefore, required time taken by train A and B to cross each other= 15 sec

4. A train starts running at a uniform speed of 60 km/h from station P towards station Q. At the same time another train starts running from station Q towards station P. If the distance between stations P and Q is 275 km and the trains meet in two and a half hours, then what is the speed of the train running towards station P in km/h?
A. 50
B. 40
C. 44
D. 48
Answer-A
Solution-Let train X starts running at a uniform speed of 60 km/h from station P towards station Q.
At the same time, another train Y starts running at a uniform speed of S km/h from station Q towards station P.
Distance between the stations P and Q = 275 km
Both trains meet in two and a half hours.
If two trains are moving towards each other then net speed will be some of the speeds of two trains.

Hence, Required speed = 50 km/hr.