Find the initial velocity of a man falling in a boat

In summary, Warren falls over his tackle box and lands in a canoe 0.95 m below the side of the dock. Warren's mass is 70 kg and the canoe has a mass of 72 kg. Warren and the canoe move 1.73 m away from the dock in 1.005 seconds. According to the event pl., there was a collision between Warren and the canoe, and momentum was changed in the process.
  • #1
Brady Aucoin
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Warren falls over his tackle box and lands in a canoe 0.95 m below the side of the dock. Warren's mass is 70 kg and the canoe has a mass of 72 kg. Warren and the canoe move 1.73 m away from the dock in 1.005 seconds.

relating equations are
Vi = Vf - at
v = d/t
A = change in velocity/time interval

Work
I was thinking that I would need to take the the velocity from the end of the problem which is 1.73 m /1.005 s = 1.72 m/s. I think that is my Vf, i just want to make sure that is correct. Because if it was the Vf i still need to find the acceleration. Any help would be appreciated.
 
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  • #2
What happens when Warren hits the canoe? Have you studied collisions?
 
  • #3
Brady Aucoin said:
Warren falls over his tackle box and lands in a canoe 0.95 m below the side of the dock.

As per the event pl. state what you wish to know? apart from given data the 'falling' part is important -how he fell verically down or in a curved path?
 
  • #4
drvrm said:
As per the event pl. state what you wish to know? apart from given data the 'falling' part is important -how he fell verically down or in a curved path?
That is the exact question and all of the information, it only asks me to find the initial velocity, that's why i am coming here because i was hoping some people who are good a physics can help me get past this question.
 
  • #5
Brady Aucoin said:
it only asks me to find the initial velocity,

i hope it is initial velocity of the canoe?

Brady Aucoin said:
Warren's mass is 70 kg and the canoe has a mass of 72 kg. Warren and the canoe move 1.73 m away from the dock in 1.005 seconds.

it appears that there was collision of the two and momentum of canoe changed- the man was on the tackle box and he fell and provided a push to the boat
he fell through a height h so he must have transferred his potential energy to a velocity of fall and ultimately his momentum to the canoe.
so now you can proceed using conservation of momentum.

if you are a physics student you know momentum is a vector so one will ask at what angle he fell and hit the canoe?

Brady Aucoin said:
i was hoping some people who are good a physics can help me get past this question.

well one can not fill in the missing words 'of a question' that will be 'guessing' the thing actually happening.
 
  • #6
Brady, please provide the complete and exact question, word for word, as given to you.
 
  • #7
haruspex said:
Brady, please provide the complete and exact question, word for word, as given to you.
it's sad to say that is the entire problem, i constantly struggle in the class but i don't think it is because of the subject, the highest grade on our most recent test was a 70%, i don't usually go online asking for help but when it comes to this worksheet i really am in disbelief on how hard it is, I'm a senior in a CP physics class, i usually am a 3.5 student and i study my a$$ off for this subject and still can't keep a C. If it really is that bad i'll just confront her about it
 
  • #8
What do you mean "entire problem"? As written in the OP there is no question asked.
 
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  • #9
nasu said:
What do you mean "entire problem"? As written in the OP there is no question asked.
To amplify on this, when you put part of the problem statement in the title of a message, you should still include that portion in the body of the message. The body should be complete and able to stand on its own. It must not depend on the thread title for context or for details.
 
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  • #10
Brady Aucoin said:
it's sad to say that is the entire problem,
ok.
Here are the ambiguities that I see. What moment in the process does "initial" refer to? Before he tripped, nearly zero. So probably it means just before he hit the boat.
What does velocity refer to? It's often used, sloppily, just to ask for speed. If so, is it the total speed (which we could get from the height fallen, if only we knew the height of the man's mass centre before he fell) or just the horizontal component (which we can get from conservation of momentum and the speed of the boat after landing)?
In each of those cases, we only need some of the information given. If it really means velocity, as in magnitude and direction, then we need to figure out both of those.
Putting all that together, my guess is it really is asking for velocity, but you don't quite have enough information. You will have to assume the height given is the height through which the man's mass centre falls.
 

1. What is the equation for finding the initial velocity of a man falling in a boat?

The equation for finding the initial velocity of a man falling in a boat is v = u + at, where v is the final velocity, u is the initial velocity, a is the acceleration due to gravity, and t is the time.

2. How is the initial velocity of a man falling in a boat different from a regular falling object?

The initial velocity of a man falling in a boat is different because it takes into account not only the acceleration due to gravity, but also the velocity of the boat at the time of the man's fall.

3. What factors can affect the initial velocity of a man falling in a boat?

The initial velocity of a man falling in a boat can be affected by the height from which the man falls, the velocity of the boat, and the acceleration due to gravity.

4. Can the initial velocity of a man falling in a boat be negative?

Yes, the initial velocity of a man falling in a boat can be negative if the boat is moving in the opposite direction of the man's fall.

5. How is the initial velocity of a man falling in a boat useful in real-life situations?

The initial velocity of a man falling in a boat can be useful in determining the impact force of the man on the boat, which can be important in rescue operations and accident investigations. It can also be used in designing safety measures for people on boats.

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