Can you tell
me how boats come to a stop ,while cruising in the water? or how
does a boat stop?
the web viewers can have fun with this one. Due to the massive
amounts of mail, I have decided to finally put this one to rest.
Here are most of the answers that we got from my e-mail box:
For power boats, it's easy: put the engine in reverse. Of course,
the sensible way to do this is to put it in neutral, let the
revolutions come down to a much lower level, and then put it in
For sailboats, well, you just gotta figure out how much momentum
your boat has. An important part of learning to sail is learning to
"depower" your boat. You drop your main or jib, turn directly into
the wind, release your sails, backwind your sails, etc. All of these
things will decrease the power your sails are extracting from the
wind. But the boat will still move. After a while, you learn to
judge how far your particular boat will coast without sails, and you
drop your sails at a certain distance from your target accordingly.
If you screw up, you either hit your target, or never make it there,
at which point you take a lap and approach it again. I've taken 5 or
6 passes at an upwind dock while sailing an unfamiliar boat. If you
wanted to get somewhere in a hurry anyway, you shouldn't have taken
stop unless you throw down the anchor, if they had parking brakes
the anchor business would go belly up. Boats when not being
artificially propelled by a motor float in the water and go the same
speed as the current (minus the effects of friction) like a raft
does. Since the boat is rather heavy the friction is large and the
boat doesn't move that much in a straight line (it does move up and
down as you can tell if you have ever been on an anchored boat in
the ocean. What gives the impression of stopping is not breaking but
the propulsion being ended. As nothing is fighting the friction to
push the boat forward once the motor is turned off the boat is over
come by the friction and slows down until it is back again at the
mercy of the current. There you go.
threw out this comment:
I did a stint with the Army Reserves as a Bridge Crewmember (12C),
and there we had breaks on our boats!!! The motors could be turned
backwards with the pull of a handle, and then we'd gun the engine
and stop on a dime (with the entire boat tipping forward in the
process (Yes, we dunked the newbies by telling them to sit on the
prow first :) hehehe )
Most boats only slow down due to the friction between the boat and
the surrounding water. What you see though is that they don't really
stop as fast as you think they do. If you are flying by on a speed
boat, and then cut the motor, your body is thrown forward (you
didn't have much friction with the air) while the boats slows down a
bunch. But if you look at the froth on the dirty lake (I haven't
been in clean lakes) you'll see you are still moving quickly. This
is caused by develocitization, the tendency of your body to get used
to a certain velocity. (Ever went from 100 MPH down to 65? You feel
like you are crawling!!!!, but mostly you are too worried about the
flashing lights behind you. :(
I hope this answer helps. I've had plenty of time on boats, and too
many times in speeding cars.
Stones came up with this idea:
It's the same with cars and aerodynamics. Big bulky cars have a
getting a high speed because of the air resistance pushing against
the front, whereas slick sports cars have less air resistance..
In the case of a boat, it's water, not air.
Jesus, even my DOG could have answered that one!
cruising the New York/New Jersey Waterway System so kindly provided
for by the respective states, I was very careful to observe the
things around me going on with the boat. I noticed a suspicious
package alone on one of the Weehawken ferries, but more relative to
the quetsion, I also noticed how the boats stopped and reversed.
They actually slowed the engines to stop and then floored it in
reverse to stop quickly (and believe me, they do stop quickly). To
go in reverse, they just kept it going. To turn in reverse, however,
they would put one prop in reverse and leave one stopped or spinning
forward. This was a two prop setup though, so I'm not sure about
other types, or what role, if any, a rudder would play in this
to "boats, no brakes"
just like with skateboards on asphalt. skateboards don't have
brakes, but if you let them go on a level surface eventually they
stop. that's the result of friction...amazing.
In the water boats experience a type of friction between water and
boat, this is caused by the weight of the boat pushing into the
water (thanks gravity, you big jerk) and some buoyancy (you know,
the thing that makes fat people float) factors in there somewhere
around the square root of ∏..or something...yeah, friction owns you.
J. Falcone expressed this:
That is easy. you put it in reverse and the motor pulls backward.
Amirsaleh pointed out:
question as to how boats stop in water
When an object is put into motion, it stays in motion forever until
acted upon by a force (one of Newton's Laws, but I can't remember
which one - couldn't that bastard have given his laws better names?)
Of course, in our world forces that work against motion such as
friction, drag, air resistance, etc. everything eventually stops,
- if you push a cart into motion and then leave it alone, it will
stop because of rolling friction between the wheels and the ground
-if you throw a ball off a really high cliff, the ball will
eventually loose its horizontal motion because of air resistance
(I'm not saying that it won't hit the bottom - I'm just saying that
it will stop moving forward and eventually just fall straight down
in a perfect vertical path)
Final Thoughts; I have learned my lesson. You guys slammed
my e-mail box into a never ending spin, it was great, you have 45
unread message in your mailbox. Keep the questions and answers
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