Question

Two cars leave one after other and travel with an acceleration 4m per s^2 . Two min after the departure of the first distance between the cars become 28km . Time interval between the departure of the cars

Answer 1

1.Time interval between the departure of the cars is 100sec

2.s=ut+1/2at² (formula)

As the cars start from rest we can consider u=0

3.1/2*4((120)²-(120-x)²)=28000

=2((120)^2-(120-x)^2)=28000

=(120)^2-(120-x)^2)=14000

x=100 or 140

4.by rejecting 140 because it is time after 2 min

so 100 sec is correct answer