Question

The driver of a train is travelling at 115km/h sees on the same track,100m in front of him,a slow train travelling in the same direction at 25km/h. The least retardation that must applied to a faster train to avoid a collosion

Answer 1

@ikram002p hlp

Answer 2

@ganeshie8 hlp

Answer 3

i think differentiation is required

Answer 4

\[\large v^2 - u^2 = 2as\]

\(u = 115-25 = 95kmph = ?m/s\)
\(v=0\)
\(s = 100\)

plug them and solve \(a\)

Answer 5

@ganeshie8 here we will use relative motio properties

Answer 6

this will give u a wrong answer

Answer 7

sorry i didn't see ur the whone thing @ganeshie8

Answer 8

no option like this

Answer 9

@hartnn hlp

Answer 10

@nincompoop @hartnn

Answer 11

pls hlp

Answer 12

@Abhisar hlp

Answer 13

@satellite73

Answer 14

@hartnn save my life tommorrow is my exam

Answer 15

\(\color{blue}{\text{Originally Posted by}}\) @ganeshie8
\[\large v^2 - u^2 = 2as\]

\(u = 115-25 =\cancel{95kmph}~90 = ?m/s\)
\(v=0\)
\(s = 100\)

plug them and solve \(a\)
\(\color{blue}{\text{End of Quote}}\)

Answer 16

an object moving with velocity x, and another with velocity y in the same direction, then relative velocity is |x-y|

an object moving with velocity x, and another with velocity y in the opposite direction, then relative velocity is x+y

Answer 17

ok its 25 i got it thnx @Abhisar @hartnn @ganeshie8

Answer 18

careful about the units

Answer 19

did u get 25 m/s^2 ?

Answer 20

http://www.wolframalpha.com/input/?i=%2895*1000%2F%2860*60%29%29%5E2%2F%282*100%29

Answer 21

no 3.125,/s^2 i was talking about velocity @ganeshie8

Answer 22

how did u get 3.125 m/s^2 ?

Answer 23

90*5/18 to convert in m/s and then pluging the values