the length of train a is twice that of train B and speed of train a is half that of train B if train crosses a man in 4 seconds and then find how long will train be take to cross trainer if they go in the same direction
Answers
1)Given,the length of train a is twice that of train b and speed of train a is half that of train b.
2)Let's assume that the length of train b be x then the train of a will be 2x.And,let's assume that the speed of train b be s then the speed of a will be s/2.
3)Then,as per given the train a crosses a man in 4 seconds then here we will consider the man as a point object.
4)Now,from the formula of speed,we know that speed=distance/time.So,when we compare or calculate the relational values between two things,then the formula will be (speed(a)*time(a))/distance(a)=(speed(b)*time(b))/distance(b).
5)Here,distance is nothing but the length of the trains.
6)By putting the values in the above formula i.e., ((s/2)*time(a))/2x=(s*time(b))/x.
7)The ans will be as time(a)=4*time(b).
8)And,here the time(a) is the time taken by the train a to cross the person which is 4seconds.By,substituting this the answer will be time(b)=1sec.Where time(b) is the time taken by the train b to cross the person.
9)Thus,the answer is 1sec.