I know this is probably going to seem like a fairly simply physics problem that I should be able to solve, however, I've been doing physics homework for the past 5 hours and my brain feels completely fried. If someone could help me get started on this, I would GREATLY appreciate it (it's my very last problem). So here it is: A boat moves through the water of a river at 8 m/s relative to the water, regardless of the boat's direction. If the water in the river is flowing at 1.0 m/s, how long does it take the boat to make a round trip consisting of a 175 m displacement downstream followed by a 175 m displacement upstream? At first I tried using the kinematic equation x-xo=vit+1/2at2 and solving for t. I assumed the acceleration was 1.0 one way and -1.0 the other way. However, the second equation (using -1.0 as the acceleration) doesn't give me a time I can use. I was planning on adding the two times together for the answer but now that isn't going to work. I'm pretty sure my brain is just fried and I should try to solve it another way, but at this moment I haven't a clue on how to get started. THANK YOU!!!!!!!!!!!!