cod double-body sailboat self-propelled model ship model technology small production small invention teacher xing manual class 鳕鱼号双体帆船自航模型舰船模型 科技小制作小发明邢老师手工课

Cod Ship Sailing Vessel

Scientific Insights: 

Why does a sailboat sail at an angle against the wind?

Place one side of the right-angled triangle ruler tightly against the horizontal tabletop. Place two fingers of the left hand on either side of it to prevent it from falling. Extend one finger of the right hand (or use a pencil) on the hypotenuse, applying pressure downward-right on the ruler. Observe where the ruler will move.   

Scientific Production: 

1,Prepare the materials needed for production.

2,Install by comparing with the image.

3Press and hold to perform debugging.

Scientific Principles:

The set square did not slide to the right, but moved to the left! What’s going on? How did the pressure below to the right become the force that caused the set square to slide to the left?

When the hypotenuse is very smooth, the effect of force F is almost identical to that of a force perpendicular to the hypotenuse and directed downward. Based on the effect of force F, we can further decompose force F into a horizontal leftward force F1 and a vertical downward force F2. Here, F1 is the force that causes the triangle ruler to slide to the left. When the frictional resistance is relatively low, it will move to the left.

When a sailboat encounters headwind, its force distribution is very similar to that of the triangular plate in this small experiment. When sailing against the headwind, a strong direct wind blows from directly ahead. We then move the bow and sail surface in two different directions to avoid contact with the direction of the headwind, allowing the wind to blow diagonally toward one side of the sail. Similar to the situation in the small experiment, the wind force F acting on the sail can be decomposed into a component perpendicular to the sail surface, F', and a component backward along the sail, F".

Obviously, F has little effect on the ship’s progress, while the component force F' perpendicular to the sail surface provides the motive force for movement. F' can be further broken down into a component force F1 along the ship’s keel line, which points in the direction of motion, and a component force F2 perpendicular to the keel line. The component force F1 naturally serves as the motive force for movement, while the component force F2, which pushes the ship sideways perpendicular to its direction of motion, is balanced by the resistance of the water in that direction. In this way, people obtain the motive force to move the ship against the wind! Therefore, a sailing ship that breaks through the wind does not actually face the wind directly; instead, it angles its bow at an acute angle to the wind direction, cleverly “facing” the wind, thereby gaining the motive force to move against the wind.

A sailboat sailing against the wind does not travel in a straight line all the time. When facing against the wind, the boat usually follows an S-shaped course to navigate around. After traveling to the left for a certain distance, the bow and sails are turned toward the right front. At this point, the wind still blows at an angle on the sails, providing the necessary power for forward movement. Thus, the sailboat successfully reaches its destination along the S-shaped route, overcoming the waves caused by the wind. Sailors often refer to this method of sailing against the wind as "rowing with the wind".

Scientific Exploration:

1Why does the vehicle move diagonally upward when driving against the wind?

2The set square did not slide to the right, but moved to the left! What’s going on?

3So how did the pressure in the lower right turn into the force for sliding the triangle tool to the left?

Product Name: Cod Ship
Model Number: C636
Size: 330*200*350 mm