Model 5 Train Vs Both platform and a man/a pole Section-Wise Topic Notes With Detailed Explanation And Example Questions

Answer: (b)

Rule 10 and Rule 1,

Let the length of train be x metre.

$x/15 = {x + 100}/25$

$x/3 = {x + 100}/5$

5x = 3x + 300

2x = 300

$x = 300/2$ = 150 metres

Answer: (c)

Let the length of train be x metres

According to question

Speed of the train = $x/10$ m/ sec.

Also, the speed of the train

= $({x + 50}/14)$ m/sec.

[Since, It passes the platform in 14 seconds]

Both the speeds should be equal,

i.e., $x/10 = {x + 50}/14$ = or 14x = 10x + 500

or 14x - 10x = 500

or 4x = 500

x = 125 metres

Hence, Speed = $125/10 = 12.5$ m/sec.

= ${12.5 × 18}/5$ km/hr. = 45 km/hr.

Answer: (b)

Rule 10 and Rule 1,

Let the length of the train be x metre

Speed of train when it crosses man = $x/10$

Speed of train when it crosses platform = ${x + 300}/25$

According to the question,

Speed of train

= $x/10 = {x + 300}/25$

25x = 10x + 3000

15x = 3000

$x = 3000/15$ = 200 metres

Length of train = 200 metre

Speed of train = $x/10 = 200/10$

= 20 m/sec

Time taken in crossing a 200 m long platform

= ${200 + 200}/20$ = 20 seconds

Answer: (a)

Rule 10 and Rule 1,

Let length of train be x m

Speed of train = ${x + 264}/20$

Also, speed of train = $x/8$

Obviously, $x/8 = {x + 264}/20$

$x/2 = {x + 264}/5$

5x = 2x + 528

5x - 2x = 528

x = 528 ÷ 3 = 176 m

Answer: (c)

Rule 10 and Rule 1,

Let the length of the train be x metres.

Speed of train in crossing boy = $x/30$

Speed of train in crossing platform = ${x +110}/40$

According to the question,

${x +110}/40 =x/30$

${x +110}/4 = x/3$

4x = 3x + 330

x = 330 metres

Answer: (a)

Let the speed of trains be x

and y metre/sec respectively,

${100 + 95}/{x - y} = 27$

$x - y = 195/27 = 65/9$ ...(i)

Again,

$195/{x + y} = 9$

$x + y = 195/9$ ...(ii)

By equation (i) + (ii)

$2x = 65/9 + 195/9 = 260/9$

$x = 260/{2 × 9} = 130/9$ m/sec.

= $(130/9 × 18/5)$ kmph = 52 kmph

From equation (ii),

$y = 195/9 - 130/9 = 65/9$ m/sec.

= $65/9 × 18/5$ = 26 kmph