In the absence of wind and currents, the boat will remain still.

when the fan is turned on, the wind created by the fan is insufficient to power the boat forward and will remain stationary.

Or maybe the weight and vibrating fan will cause an opposite pulling force and cause the boat to go in circles in the same spot.

Will provide answer to riddle later.

The 'correct' answer from the judging panel was the boat goes forward, and it was argumented as follows: the fan's wind caused a pressure on the sail causing it to move forward tensioning the sail, and with this it pushed the mast hence boat forward. This is bull because the fan's forces don't feature in this at all, however many entries on the net preach this false answer as gospel.
The law of impulse (action=reaction) is a more complete representation of the forces at work: the fan creates a force backward buy pushing air forward, however the (much bigger) sail 'catches' all this wind causing it to exert the exact same force forward... and therefore the boat will not move. Again many entries favouring this answer will be found on the net.
However, there's friction hence an efficiency at work: the by the fan ejected air is moving/turbulent and loses speed, and by the time it reaches the sail some of the speed hence energy has been lost - which causes the force on the sail to be less than that of the fan.
It is for this reason that the boat will move backwards - and it will too.

A boat floating in water is akin to a shaft spinning in an oilfilm in a white-metal bearing: it does not make any mechanical contact as it is completely suspended by a fluid, therefore the friction is quite low . A floating boat is comparable in this sense, therefore it takes a minute force only to create movement of the boat: even with a small fan the boat will move. However, take the sail off, turn the fan around, drive it with an engine and one gets a fan-propelled boat many of which do service around the world, the Everglades spring to mind.


Look forward to the A's for the riddles.

What am I?

1. My life can be measured in hours,
I serve by being devoured.
Thin, I am quick
Fat, I am slow
Wind is my foe.

2. I can be small, I can be big
And with friends I dance and jingle,
Hide and seek is my favourite game
And it's more fun when I am single.
What force can take days to do
I can do it in seconds.

Answer to 1. A candle

Answer to 2. A key

Dam, I would never have guessed that!

1) If you have only one match and you walked into a room where there is an oil burner, a kerosene lamp, and a woodburning stove, which would you light first?

2) How many animals of each sex did Moses take on the Ark?

3)Two men play five games of checkers. Each man wins the same number of games. There are no ties. Explain this.

4) Why can't a man living in the USA be buried in Canada?

5) If there are three apples and you take away two, how many do you have?

1. The match

2. Noah took animals to the ark, not Moses

3. They each won 2 games each, the fifth game is still in progress.

4. The man is still alive, he is not dead

Number 3 is wrong .
What about the answer for question 5 ?

Woahhh i think i spot the trend in the q's!

That then makes it 2 apples-> tell me i'm right :)

On 2016-03-07 11:11:04 Executive123 said:
Woahhh i think i spot the trend in the q's!

That then makes it 2 apples-> tell me i'm right :)

You are right boss

Number 3. the players are not playing each other?
Number 5. ?