Question

The initial distance between two particles A and B is 300 meters. The particles head towards each other at speeds of 1.5 m/s and 3.5 m/s respectively. When will they meet?

Answer 1

Let the distance travelled by A be x and. distance travelled by B be (300-x)m

Let the both Particle will meet after t second.

For Particle A

Speed = 1.5sec

Distance travelled by A = x

Time taken = t

We know that,

Speed = Distance travelled/Time taken

1.5 = x/t

x = 1.5t

Again,

For Particle B

Speed = 3.5sec

Distance travelled =300-x

Time taken = t

We know that,

Speed = Distance travelled/Time taken

3.5 = (300-x)/t

3.5t = 300 - x

3.5t = 300 - 1.5t

300 = 3.5t + 1.5t

300 = 5t

t = 60 Sec

Extra :- if it is also asked to find distance travelled by both Particle;

x = 1.5t

x = 1.5 *60

x = 90m.

So,

Distance travelled by A = 90m

Distance travelled by B = 300-90

= 210m