1. Mechanics: ① Force can change the shape of an object: pinch it hard to flatten it. ② Under the same conditions, the rolling friction force is less than the sliding friction force (or static friction force): build an inclined plane, let the cans roll down vertically, and compare the distance. ③ Liquid pressure: Scheme 1: Press the top seal of the can into the water to compare the deformation of the can at different positions; Option 2: make a few holes on the side to see the distance of water flowing out; Scheme 3: Cut the jar into a cylinder, tie three round holes in the side, seal the side and bottom with a rubber film, and then pour water to see the protruding degree of the rubber film. First, it can prove that the water pressure is related to the depth, and second, it can show that the water pressure is omni-directional.

2. Heating: ① Put ice (or dry ice) into the tank and stir it with chopsticks, and the bottom of the tank will be frosted. ② Fill the jar with water, seal the top with a rubber stopper (be careful not to screw it too tightly), and heat it to make the rubber stopper rush out, so that the internal energy in the demonstration can be converted into mechanical energy.

3. Sound phenomenon: it can be proved that sound is produced by the vibration of objects, or changes the tone, etc.

4. light phenomenon: bottom ... 1. mechanics: ① force can change the shape of an object: pinch it hard to make it flat. ② Under the same conditions, the rolling friction force is less than the sliding friction force (or static friction force): build an inclined plane, let the cans roll down vertically, and compare the distance. ③ Liquid pressure: Scheme 1: Press the top seal of the can into the water to compare the deformation of the can at different positions; Option 2: make a few holes on the side to see the distance of water flowing out; Scheme 3: Cut the jar into a cylinder, tie three round holes in the side, seal the side and bottom with a rubber film, and then pour water to see the protruding degree of the rubber film. First, it can prove that the water pressure is related to the depth, and second, it can show that the water pressure is omni-directional.

2. Heating: ① Put ice (or dry ice) into the tank and stir it with chopsticks, and the bottom of the tank will be frosted. ② Fill the jar with water, seal the top with a rubber stopper (be careful not to screw it too tightly), and heat it to make the rubber stopper rush out, so that the internal energy in the demonstration can be converted into mechanical energy.

3. Sound phenomenon: it can be proved that sound is produced by the vibration of objects, or changes the tone, etc.

4. Light phenomenon: the bottom is perforated, the back is sealed with translucent paper, and small holes are imaged.

That's all I can think of.