What are the small productions of the first volume of science in grade five (Beijing Normal University Edition)?

1 reference materials. Three or four 2.5-liter Jianlibao bottles or Coke bottles, several X-rays, several No.3 and No.4 soft rubber stoppers for chemical equipment, a complete set of bicycle valves, a pair of scissors and a knife, transparent adhesive, double-sided adhesive tape and insulating tape, and a piece of 502 adhesive.

2 wing making. Cut the X-ray film into 28 right-angled trapezoidal blocks with the same size with scissors. The trapezoid is 12cm long and 6cm high, and the included angle between the inclined waist and the long bottom is about 45 degrees. In addition, four trapezoids with the same specifications but 8cm high are cut out, the short bottoms are connected and the two sides overlap (used as wing surfaces). Use double-sided tape to closely stick seven small trapeziums into a thick trapezium to make it flat, and then tightly wrap and stick it with a large double-sided trapezium. In order to make the thick surface of the wing flat, it can be flattened and straightened with scissors or a knife, and then the thick surface of the wing can be sealed with insulating glue. Finally, the parts that grow on both sides of the wings are folded 90 degrees outward. In this way, the remaining X-rays are made into three wings according to the above method.

3 fuselage production. Take a Jianlibao bottle (the curvature of the bottle head is too natural, which is conducive to reducing the air resistance as a rocket head), cut it horizontally from the lower end 1 1cm, stick the part with the bottle mouth to the bottom of another bottle with insulating glue, and wrap the interface firmly with insulating glue.

4 air plug making. Take a No.4 soft rubber plug, open a flat hole slightly smaller than the valve core sleeve in the middle of the bottom of the rubber plug with a hole-opening tool, and then cut off the fine end by about 0.6cm； with a knife; Put a big "ring" on the valve core (sold in hardware stores), install the valve core upward from the thin end of the soft rubber plug, put on the same "ring", screw on the screw and tighten it slightly. Finally, grind the gas plug into a cylindrical shape with a grindstone until it can completely enter the coke bottle mouth or be slightly tight, and then the valve core can be used.

5 gun head production. Take a No.3 soft rubber stopper and sharpen it with a knife.

6 Assemble the wing. Take a Jianlibao bottle, cut a cylinder slightly longer than the wings, and then closely glue the four wings into four parts with transparent glue and insulating glue. Finally, put the cylinder with wings attached to it at the bottom of the water rocket so that it is flush with the bottle mouth (this is not necessarily the best position, but it can be adjusted up and down in flight practice to find it), and wrap it with insulating glue to make it stick firmly.

7 others. In order to increase the contact surface between the air plug and the bottle mouth and increase the air pressure in the bottle, the big end of the air plug can be thinned with a knife to make it flat and rough. Because the fuselage has the rocket head part, so the rocket head part is relatively light and unbalanced, so it can be properly stuffed with paper to achieve balance. In order to reduce the air resistance as much as possible, the gun head made of soft rubber plug will be glued to the bottle mouth of the rocket head with 502.

According to the above method, a simple water rocket was made. According to the water rocket developed by us, through practical improvement, the horizontal flight can reach about160m, and the vertical flight can reach 40 ~ 50m.

Water rocket launching method:

1 water regulation. There is a certain proportion between the water consumption of water rockets and the air space of rockets, neither more nor less. The optimum water consumption is about1/4 ~ 2/5 of the rocket air space (the space of 2.5 liters is about 600 ml, which can be determined by multiple tests).

2 launch angle. For horizontal flight, the optimal launching angle is between 50 and 55 degrees due to air resistance, which may be different for different water rockets and can be determined by controlling variables. The best angle of our water rocket is about 53 degrees. Vertical flight is 90 degrees.

3 air plug use. The use principle of air plug is to adjust the tightness of air plug by compressing the volume expansion of soft rubber plug. The greater the compression, the greater the volume expansion, the tighter the air plug, and the greater the air pressure that washes the air plug, that is, the greater the power that the rocket gets. The specific use method is: firstly, remove the valve core of the valve plug, insert the valve plug into the bottle mouth of the rocket as it is, then tighten the screw of the valve plug with a sleeve (a special tool for screwing screws, which is sold in hardware stores), and finally install the valve core to be used for inflation. (Note: The tightness can be adjusted as required. )

4 launch stability control. Only horizontal launch is discussed. Need to make a launch pad, the launch pad should have a navigation track, the navigation track should not be too long or too short, generally 60cm long (three teaching triangles and two broomsticks can be spliced together, in order to reduce the friction of the broomsticks on the water rocket when they are used as navigation tracks, the broomsticks or the models shown in the legend can be pasted with transparent glue). When there is no wind, the target is launching at the best launching angle (the angle between the launching track and the ground). In windy weather, the direction of the target should be properly adjusted according to the wind force and direction to maintain the best launching angle.

5 precautions. When launching, make sure that the rocket is straight and consistent with the orbit. If it deviates from 1~2 degrees, it will affect the flight stability and fly in the shape of "8" When pumping air, it should be as smooth as possible, and the pumping frequency should be fast, not too slow. In order to tighten the air plug as much as possible, it can be adjusted by tightening the screw of the air plug. The tighter the air plug, the greater the air pressure in the bottle, and the greater the power of the rocket.

Take the first bottle and call it a bottle. Draw a line above and below 1- 1 and 2-2 of the bottle, and determine the positions of the two lines as follows.

1- 1: Select the place where the curvature of the arc on the bottle is similar to that of the rocket foam head.

2-2: Select a place about 0.5cm below the straightening point of the bottom curve of the bottle.

Cut (cut) with a artistic knife (or scissors) from the place about 0.5cm above 1- 1 line and below 2-2 line.

Trim it slowly to the drawing line with scissors, as flat as possible, so that it can be more closely connected with bottle B.

Put the rocket foam head above bottle A, and see if the foam head is in the center of the bottle from the top. If it has been put away, wrap it around the joint with electrical tape and fix it.

Take another bottle called bottle B, take off the cap, and then tighten the nozzle from the mouth.

Connect bottle a and bottle b. Then, as for the flat desktop or rolling on the ground, see if the connection is smooth and whether the rolling is smooth. If there is, fix it with electrical tape.

Connection completion diagram

Take the third bottle, called bottle C, and draw a line at the positions of 3-3 bottles and 4-4 bottles.

3-3: Select 0.5cm below the turning point of the curve above the bottle.

4-4: Select 0.5cm below the turning point of bottle bottom curve.

Cut (cut) with a utility knife (scissors) at about 0.5cm above line 3-3 and below line 4-4.

Bottle completion drawing

Fold the cardboard in half, and then draw four trapezoids with a pencil. Then cut it along the line with scissors.

Note: the size and shape of the tail can be changed to test its influence on flight.

Similarly, slide the film and make it into a trapezoid with the same specifications as the cardboard.

Wrap the prepared glass slide on the outside of the cardboard trapezoid. First, stick the slides and cardboard together with double-sided tape, and then stick them on three sides with electrical tape.

Stick the double-sided adhesive tape to the bottom of the folded part. This step is to stick four complete mantissa years on bottle C.

Four-tailed completion drawing.

Stick the four tail fins on the C bottle, and be sure to cross symmetrically, so as to be balanced.

First, stick electrical tape on both sides of the tail wing. When pasting, pay attention to the length of electrical tape. The upper part is about one tape higher than the tail wing, and the lower part should be folded back to bottle C to increase the firmness. Then wrap insulating tape around the tail wing for about two turns.

Connect bottle C and bottle B with electrical tape.

Note: It is also necessary to keep the water rocket body straight to ensure the accurate flight direction.

Full picture of water rocket in baote bottle.

First, the small balance

Tips: It must be done with the help of parents!

1. First cut the plywood into four pieces: A, B, C and D.

2. The bottom opening of B is the middle opening of C and D..

3. Insert three thin strips as shown in the figure.

4. Nail A to the middle and upper section of B, but be careful not to nail it to death, and be able to move freely.

5. Cut the crescent-shaped target board with plywood and mark it with scales.

6. Cut a small piece and fix it on A with all-purpose glue, as shown in the figure.

7. Cut two disks of equal size.

8. Make four holes at the top.

9. cut a small ditch on each side of a.

10. Tie the chip with a thin thread, and the balance will be done.

Next, you can use your imagination to decorate the small balance and use it as a gadget after the experiment. It's killing two birds with one stone!

Image: /image/6982.jpg

Second, the actor walks a tightrope.

Actors always carry a long stick when walking a tightrope. Maybe everyone will think, isn't this an increase in the burden on actors? When you finish the following experiment, you will change this view.

I. Materials

A blank board, a 10 cm-long iron wire, a thumbtack, a lump of plasticine, a 30 cm-long and 2 cm-wide thin iron sheet, adhesive tape, glue, scissors, ruler, etc.

Second, production.

1. Cut it into the shape of a villain with cardboard, draw the five senses, color it, and stick a support bar behind it. The villain's feet are folded forward and the support rod is folded back. Stick a thumbtack with glue, cut off the extra part, and fold back the thumbtack tip.

2. Straighten the wire, pinch two balls of the same size with plasticine, fix them at both ends of the wire, and then stick the middle of the wire on the villain's "hand" with tape, so that the villain can stand.

3. Touch the center paper of the iron sheet vertically with a ruler, fold the iron sheet into a right angle, put it on the table with the angle down, then fix it with adhesive tape, put the upright villain, align the nail hook with the groove, and let the villain slide down slowly from the upper end to keep it smooth.

Third, reveal secrets.

Objects are attracted by the earth, and the balance of objects depends on the position of their center of gravity. The lower the center of gravity, the more stable the object is. A long and drooping stick can lower the center of gravity, and the increase of weight is also beneficial to balance. Therefore, an actor walks a tightrope with a stick.

Image: /image/626 1.jpg

Third, make a hot air balloon (Kongming Lantern)

Let's make a hot air balloon together. The hot air from the hair dryer can make it rise slowly, just like a real hot air balloon.

1. First, we cut 6-8 leaflike pieces of paper from soft paper.

2. Fold them in half and stick the edges together to make a balloon.

3. Stick the four connecting wires to the bottom of the balloon with adhesive tape. Fix the other end of the line on the table with plasticine.

Try to set the speed of the hair dryer very slowly. Aim the air outlet upward at the opening at the bottom, and then turn on the switch. The balloon will gradually get bigger, tighten the line and leave the table.

You can be a turtle sweeping the floor. You have a shoe brush. Grind off the handle of the shoe brush, press the motor on it, then stick a cake plate on it, do some decoration, start the motor, and the little turtle will leave!

Prepare materials and tools for making sand table: chassis, track, pigment, grass powder, turf, silicone gun, waste newspaper, white glue, gypsum, etc.

According to the need, you can design the shape and height of the track yourself and add it with hot silica gel. (Note: it must be firmly bonded, and there can be no looseness or inclination. )

Stick masking paper on the track to prevent impurities from entering in the production process and should not be removed. Molded into a pre-designed shape with waste newspapers, it can be fixed with masking paper, then covered with plaster bandage and sprayed with water.

After the basic shape is fixed, pouring gypsum will make the whole shape more three-dimensional and easy to color. (Note: avoid the track when pouring gypsum)

Glue the building to the already made shape.

Color, color is to pay attention to draw dark color first, then draw medium color, and finally draw highlights, weathering effect, and then plant vegetation.

Plant vegetation and sprinkle grass powder, and the simple sand table will be basically ready. Finally, don't forget to hit the track with sharpie, and it's over.

Make a Kongming Lantern!

It can fly by itself!

2. 1 materials and production

① Take a large and thin plastic handbag and cut it flat in the portable part.

(2) Take a thin copper wire with a length of about 60cm (one of many soft copper wires can be used), and tie both ends to both sides of the opening of the convenient bag.

③ A simple Kongming lantern was made by wrapping a proper amount of cotton in the middle of a thin copper wire. As shown in the figure.

2.2 release

Choose a place where there is no wind (or indoors). One person holds the two corners at the bottom of the convenient bag with both hands, so that the opening is downward, and the thin copper wire wrapped in cotton naturally hangs down. Pour a proper amount of alcohol on cotton and light the alcohol. In a few tens of seconds, Kongming Lantern will fly.

2.3 attention

① Alcohol cotton should not be overweight. Generally, it can make the total mass (the total mass of convenient bag, fine copper wire and alcohol cotton) easier to take off below 5g.

(2) The length of thin copper wire should be appropriate to avoid dissolving plastic bags after alcohol combustion, and pay attention to fire prevention.

(3) If you want to pull it down, you can tie a thin copper wire in the middle of the thin copper wire in advance to make it droop.

Actors always carry a long stick when walking a tightrope. Maybe people will think, isn't this an increase in the burden on actors? When you finish the following experiment, you will change this view.

I. Materials

A blank board, a 10 cm-long iron wire, a thumbtack, a lump of plasticine, a 30 cm-long and 2 cm-wide thin iron sheet, adhesive tape, glue, scissors, ruler, etc.

Second, production.

1. Cut it into the shape of a villain with cardboard, draw the five senses, color it, and stick a support bar behind it. The villain's feet are folded forward and the support rod is folded back. Stick a thumbtack with glue, cut off the extra part, and fold back the thumbtack tip.

2. Straighten the wire, pinch two balls of the same size with plasticine, fix them at both ends of the wire, and then stick the middle of the wire on the villain's "hand" with tape, so that the villain can stand.

3. Touch the center paper of the iron sheet vertically with a ruler, fold the iron sheet into a right angle, put it on the table with the angle down, then fix it with adhesive tape, put the upright villain, align the nail hook with the groove, and let the villain slide down slowly from the upper end to keep it smooth.

Third, reveal secrets.

Objects are attracted by the earth, and the balance of objects depends on the position of their center of gravity. The lower the center of gravity, the more stable the object is. A long and drooping stick can lower the center of gravity, and the increase of weight is also beneficial to balance. Therefore, an actor walks a tightrope with a stick.

Making pinhole camera

Method:

Pinhole camera

According to the principle of pinhole imaging, a pinhole imager can be made and a clear image can be seen on its screen. If you put a photosensitive film on the screen, you can take a clear picture and become a pinhole camera. However, this requires a "shutter" and a slot for loading negatives. In addition, the requirements for sealing are stricter than those for making ordinary pinhole imagers.

The structure of pinhole camera is shown in Figure10.6-L. The camera body is made of toilet paper and is divided into two parts: the front cover and the back cover.

manufacturing method

Draw it on the toilet paper according to the size of figures 10.6-2, 10.6-3, 10.6-4 (δ is the thickness of toilet paper), cut it along the solid line of each figure, and then gently carve it with a knife along the dotted line. Don't cut it, so as to fold the straight edge when bending. Then paint both sides of each block black.

Bend the cut front cover outer layer development drawing (Figure 10.6-2) by 90 degrees along the dotted line to form a five-sided paper box, and stick it with adhesive tape. Then stick a piece of 120 film black lining paper on one side with a round hole, and tie a small hole with a diameter of about 0.4 mm on the lining paper in the center of the round hole with a needle (the diameter of 12 sewing needle is about 0.4 mm). Then, as shown in figure 10.6- 1, stick a paper slot on the edge of the small hole and insert a hard paper strip in the paper slot, which can be used as a blind and keep the small hole clean.

Bend the cutting development diagram of the inner layer of the front cover (Figure 10.6-3) by 90 degrees along the dotted line, make it into a square cylinder, and attach the joint (the tongue is attached to the inside of the square cylinder). Then, fold the trapezoidal tongue at the notch end into a paper frame, align the notch with the reinforcing frame (Figure 10.6-4) and stick them together. Cut a paper frame with cardboard according to the size of the reinforced frame, align the gap and stick it on the reinforced frame, and stick this paper frame with the square tube outside with adhesive tape, so that a paper slot is formed between the reinforced frame and the rigid paper frame, and the negative can be loaded or taken out from the notched side. This gap is designed to facilitate the loading and unloading of negatives. After the inner layer is finished, the outer layer should be glued, that is, each trapezoid uvula at the other end of the square tube should be bent 90 degrees along the dotted line, coated with glue, aligned with the gap, and inserted into the outer layer. At the same time, a piece of toilet paper should be inserted between the inner layer and the outer layer of each face to ensure the same gap between the inner layer and the outer layer. After the front end of the inner layer is stuck to the surface with a round hole in the outer layer, the inserted toilet paper is pulled out, and the front cover is completed.

As for the manufacture of the back cover, except that the side width is 80+26 mm and there is no hole in the bottom surface, everything else is the same as the outer layer of the front cover. You can refer to the development diagram and corresponding dimensions of the outer layer of the front cover to make it.

Application mode

1. The pinhole camera has a fixed image distance of about 64 mm and a fixed aperture of 0.4 mm, so the aperture is also fixed. Experiments show that the pore size is about 160. When the brightness of the subject is different, it can only be adjusted by exposure time. Because the aperture number of a general camera is about 22, it is impossible to find out the exposure time of aperture 160, so it can be determined according to the ratio of exposure time equal to the square of aperture ratio (that is, t 1: t2 = (f 1: f2) 2). For example, when shooting a scene, the exposure time of aperture 16 is 1/30 seconds, then the exposure time of pinhole camera aperture 160 should be 3.3 seconds. The best exposure time should also be determined by experiments.

2. When taking photos with a pinhole camera, the framing method is shown in Figure 10.6-5. Stick one eye at the midpoint of one side and look out at the opposite ends. Then, the part sandwiched at this angle is the range to be taken. Moving the distance between the camera and the scene can change the image size.

3. Exposure: Take a good picture, calculate the exposure time, open the cardboard covering the small hole and close it until the scheduled exposure time.

4. Film loading and unloading: a single 60×60 mm 2 film is often difficult to buy, so it needs to be cut with a large film. Film loading, unloading and film cutting should be carried out in a dark room without light.

Matters needing attention

1. Be careful not to leak light when making.

2. Pinholes should be round and smooth.

3. Due to the long exposure time, it is advisable to shoot still life.

Ruler (30 cm long), candle, soft paper, thread, transparent tape.

How?

1. Make a spiral belt with a diameter of about 6cm with soft paper and draw a snake head in the middle.

2. Cut the thread into about 15cm long and stick it on the snake head with adhesive tape.

3. Hold one end of the thread with your hand and put the paper snake 20 cm away from the candle to see what will happen.

At this point, you will find that the paper snake is spinning and dancing.

Why is this?

When a lighted candle heats the air above it, the air becomes hot and expands the distance between air molecules. The heated air becomes lighter and then rises, while the surrounding cold air rushes to its position. The hot air is pulling the paper snake in the rising, so it makes it dance. Hot air rises and cold air falls. This repeated circulation of air is the cause of the wind. )