Question

Tom and Donna decide to have a swimming race across a 200m wide lake. Tom gives Donna a head start and waits until she is half-way across the lake before jumping straight down into the water. What minimum acceleration must Tom have to just barely win the race if Donna is swimming at a constant speed of 1.5 m/s? What is his final speed?

Answer 1

Donna swims the lake at a constant speed

Time taken by Donna to complete first half of the total lake's width ( ) is ,

Donna takens another to complete the remaining half.

So to just barely win over Donna , Tom has to cross the lake in a time starting with initial speed

Using

Tom's final speed is