# Homework Help: Motion in one dimension of a swimmer

1. May 23, 2004

### Alice-Shallom

Hi, i need help with the following:

One swimmer in a relay race has a 0.50-s lead and is swimming at a constant speed of 4.0 m/s. He has 50 m to swim before reaching the end of the pool. A second swimmer moves in the same direction as the leader. What constant speed must the second swimmer have in order to catch up to the leader at the end of the pool?

I understand that since the 1st swimmer swims at constant speed, he has zero accelaration.

Is it useful to use this formula? Speed = Distance / Time
If not, which formula can i use?

Thanks.

2. May 23, 2004

### Staff: Mentor

Both swimmers swim at constant speeds. And, yes, V = D/T will be very useful.

Ask yourself: How much of a lead (in distance) does the first swimmer have? How long is the pool? How long will it take the first swimmer to reach the end?

Then ask: How fast must the second swimmer swim if he is to get all the way across the pool in the same time that the first swimmer takes to swim 50 m?