Question

Two trains travelling on the same track are approaching each other with equal speed of ` 40 m//s`. The drivers of the trains beging to decelerate simultaneously when just ` 2.0 km apart. Assuming deceleration to be uniform and equal the value to the deceleration to barely avoid collision should be .
A. (a) ` 0.8 m //s^2`
B. (b) ` 2. 1 m//d^2`
C. (c ) ` 11 .0 m//d^2`
D. (d) ` 11 .8 m//d^`

Answer 1

Correct Answer - A
Here, ` u= 40 m//s : destance to be cvered by each train before rest ` S= 1000 m, v=0 , a = "? ` Using the relatin ` v^2 =u^@ + 2 aS, we have ltbgt ` a=((v^ -u^2)0/(2 s) = (0- (40)^2)/(2 xx 100 0 = 0.8 m//s^2` .