Preparation materials: an empty beverage bottle, two foam fruit net sets, a rubber band, a glass bullet.
Process:
1. Take an empty 250 ml beverage bottle, cut off the top half of the bottle;
2. Cut the part of the cut into eight parts, cut with scissors to the neck of the bottle, and then, each part of the cut into the shape of a petal of the same size;
3. Foam fruit mesh set outside the bottle, fixed with a rubber band at the mouth of the bottle;
4. Wrap another foam fruit net cover around a glass bullet, stuff it into the mouth of the bottle, stuff it tightly and expose it for about 1 cm;
5. Cut half a ping pong ball, cover the bottom of the hemisphere over the mouth of the bottle, cut the four edges into whiskers, cover the mouth of the bottle and then fasten it with a rubber band.
6. Beautify the finishing touches, a homemade badminton completed. Play with a badminton racket, see how the effect?
2, homemade soap paper
Materials and tools:
White paper with good moisture absorption, a small piece of soap, a brush and disposable beverage cans.
Making Methods:
First, the soap is chopped up and placed in the can, filled with the right amount of water and put the cup on the stove to heat up the soap melting, cut the white paper into a matchbox size, a sheet coated with soap, and then take out the drying of the soap paper.
3, homemade hot air balloon
1. First we cut out 6 to 8 leaf-shaped pieces of soft paper.
2. Fold them in half and glue their edges together to make a balloon.
3. Tape four strings to the bottom of the balloon. Use playdough to attach the other end of the strings to the table.
4. Turn the hairdryer on as slow as possible. Point the mouth of the hairdryer upwards towards the opening at the bottom and turn the switch on. The balloon will slowly grow in size and pull the cord tight and off the table.
4, homemade flashlight
Specific production methods are: a waste cans (such as Lulu beverage cans) up off one end of the lid, the other end of the round hammer knocked concave. Roll up two #1 batteries on thick corrugated cardboard, with the positive end facing up and the negative end facing down, and put them into the can. Find a suitable plastic lid (e.g., a magical large rolled box lid that fits over the Lulu can) and dig a small round hole in the center of the lid, large enough for the light bulb to fit into. Insert the bulb base into the hole. Take a piece of wire and strip the ends of the wire, wrap one end around the base of the bulb, and pierce the other end through a small hole in the side of the plastic lid. Put the plastic cover on the can. Check to see if the bulb and battery are making tight contact. Here the disposable flashlight is ready. Use, with the thumb from the side wall through the wire pressed from the cans without paint on the weld, the flashlight will glow, thumb away from the wire jump up, the flashlight will go out, the use of very convenient.
5, homemade solar cooker
Find a large flashlight on the concave reflective bowl, with rigid foam or wood to cut a cylinder about 4 centimeters long, the diameter of the reflective bowl can be tightly plugged into the round hole appropriate. At one end of the cylinder drilled a fine hole horizontally, through a diameter equal to the hole diameter of the wire, and then exposed in the cylinder outside the wire ends wrench folded into 90 °, each left 5 cm can be. Plug the cylinder into the round hole of the reflective bowl, and then insert the ends of the wire into a piece of foam or wooden base plate. Sharpen both ends of a thin bamboo skewer and insert one end into the cylinder in the center of the reflector bowl and the other end into a small piece of potato. Place the device in the sun with the bowl facing the sun and patiently adjust the length of the stick so that the potato is in the center of the light. In no time at all, the potato will be cooked by the sun's rays and will give off its flavor.
6, homemade colorful candles
Materials: color crayons, wax
Methods:
1. Find a discarded canned beverage barrel (such as 1.25-liter Coke bottles), neatly cut off the lid of the part of the wax chipped into the barrel.
2. Put the bucket in hot water and stir the wax inside to melt it all. It's best to use boiling water. But ask your parents for help or do this step under their supervision.
3. Pour the melted liquid into a nicely shaped container (such as a heart-shaped box with small pieces of choconai). Don't pour too much. As for why, read on. Of course, you'll want to put the thread for the wick in the container first.
4. When the original wax has cooled, pour in the melted colored crayon liquid (colored crayons come in handy here) as you did on the other side. In this way, the different colors of wax layer by layer to add, good-looking candle is made.
7, homemade wall hanging baskets
Materials and tools: two Sprite bottles, glue, carving knife, scissors.
Methods:
1. Remove the green bottom set of a Sprite bottle, cut it into a lotus shape, turn it down and glue the bottle into a base.
2. In the green bottom set intercepted 2 cm wide green ring, still set on the bottle.
3. Remove the neck of the bottle, cut out a 13 cm long and 8 centimeters wide wide band on the bottle, and a number of 3 cm wide narrow band.
4. Use a carving knife to carve a pattern on the 3-centimeter narrow strips as shown in Figure 3, then fold these narrow strips outward and insert them into the green ring from the bottom up.
5. Take another bottle and use the bottle to cut six 17 cm capsule leaves with scissors.
6. Nail the basket to the wall, insert the leaves and flowers, and the wall-mounted basket is made.
8, homemade cockroach capture box
Take a piece of cardboard 220 × 150 (mm).
The most important part of the capture box is the capture surface. Take a piece of plastic film, cut it to the same size as the bottom of the box, apply adhesive and lay it on the bottom of the box. Cockroaches can be caught, the key lies in the adhesive. Adhesive has two functions: one is to introduce cockroaches into the box, and the other is to stick them on the catching surface. Preparation of luring agent: Mix 40% meat powder, 50% flour and 10% soybean cake, the total amount is about 20 grams, mix well and wait for use. Adhesive is 20 grams of rosin mixed with 10 grams of vegetable oil, heated to a gelatinous state, the lure and the adhesive mixed and stirred well, that is, made of adhesive.
To mix the above paste evenly coated in the plastic film has been lined with the capture surface, and then folded inward according to the original drawing of the dotted line, and finally the tongue b inserted in the notch a.
Because of the non-drying nature of the rosin and vegetable oil mixture, the bait can be made sticky for up to a week. Place the box in a cockroach-infested area. Because the box is darker and has a bait that the cockroaches like, the cockroaches will crawl into the box and fight for the bait and get stuck to it. Sticky full, both the carton can be flattened and discarded, but also remove the plastic film, plastic film coated with bait, so that the box can be reused.
If the size of the capture box is expanded, and the composition of the adhesive will be slightly adjusted to thicken the coating can be made of paper mousetraps.
References:
When I eat, I use my chopsticks to pinch the beans. It was always impossible to clip them. Then I thought, beans are round: if the chopsticks clip food at one end to dig a semicircular notch on the line, try to make a pair of such chopsticks, go to clip beans, everyone said it is very convenient! The first thing you need to do is to make a pair of chopsticks that can be used to hold food. The owner to give points !!!!!
Responders: 805402586 | Grade 4 | 2010-3-10 20:30
Innovative small invention production methods 1, homemade badminton
Preparation of materials: empty beverage bottles, a foam fruit net set of two, rubber bands, a glass bullet.
Production process:
1. Take 250 ml empty beverage bottle a, the top half of the bottle cut off;
2. Will cut off the part are divided into eight parts, cut with scissors to the neck of the bottle, and then, each part of the cut into the same size of the shape of the flower petals;
3. Foam fruit mesh set outside the body of the bottle, fixed in the bottle with a rubber band at the mouth of the bottle;
4. Wrap another foam fruit net cover around a glass bullet, stuff it into the mouth of the bottle, stuff it tightly and expose it for about 1 cm;
5. Cut half a ping pong ball, cover the bottom of the hemisphere over the mouth of the bottle, cut the four edges into whiskers, cover the mouth of the bottle and then fasten it with a rubber band.
6. Beautify the finishing touches, a homemade badminton completed. Play with a badminton racket, see how the effect?
2, homemade soap paper
Materials and tools:
White paper with good moisture absorption, a small piece of soap, a brush and disposable beverage cans.
Making Methods:
First, the soap is chopped up and placed in the can, filled with the right amount of water and put the cup on the stove to heat up the soap melting, cut the white paper into a matchbox size, a sheet coated with soap, and then take out the drying of the soap paper.
3, homemade hot air balloon
1. First of all, we use soft paper cut out 6 to 8 leaf-shaped pieces of paper.
2. Fold them in half and glue their edges together to make a balloon.
3. Tape four strings to the bottom of the balloon. Use playdough to attach the other end of the strings to the table.
4. Turn the hairdryer on as slow as possible. Point the mouth of the hairdryer upwards towards the opening at the bottom and turn the switch on. The balloon will slowly grow in size and pull the cord tight and off the table.
4, homemade flashlight
Specific production methods are: a waste cans (such as Lulu beverage cans) up off one end of the lid, the other end of the round hammer knocked concave. Use thick corrugated cardboard to roll up two batteries, the battery positive side up, negative side down into the can. Find a suitable plastic lid (e.g., a magical large rolled box lid will snap right onto the Lulu beverage can), and dig a small round hole in the center of the lid, the size of which is appropriate to allow the light bulb to be inserted tightly. Insert the bulb base into the hole. Take a piece of wire and strip the ends of the wire, wrap one end around the base of the bulb, and pierce the other end through a small hole in the side of the plastic lid. Place the plastic cover over the can. Check to see that the bulb and battery are not in close contact. Here the disposable flashlight is ready. When using, use your thumb to put from the side wall through the wire pressed from the can without paint on the weld, the flashlight will glow, thumb away from the wire jumped up, the flashlight will go out, the use of very convenient.
5, homemade solar cooker
Find a large flashlight on the concave reflective bowl, with rigid foam or wood to cut a cylinder about 4 centimeters long, the diameter of the reflective bowl can be tightly plugged into the round hole appropriate. At one end of the cylinder transversely drilled a fine hole, threaded into a diameter equal to the diameter of the hole in the wire, and then exposed in the cylinder outside the wire ends wrench folded into 90 °, each left 5 cm can be. Plug the cylinder into the round hole of the reflective bowl, and then insert the ends of the wire into a piece of Styrofoam or wooden base plate. Sharpen the ends of a thin bamboo skewer and insert one end into the cylinder in the center of the reflecting bowl and the other end into a small piece of potato. Place the device in the sun so that the reflective bowl is facing the direction of the sun, and then, patiently adjust the length of the bamboo skewer so that the inserted potato sits right on the glowing focal point. It won't take long for the potato to be cooked by the sun's rays and give off flavor.
6, homemade colorful candles
Materials: color crayons, wax
Methods:
1. Find a discarded canned drinks barrel (such as 1.25-liter Coke bottles), neatly cut off the lid of the part of the wax chipped into the barrel.
2. Put the bucket in hot water and stir the wax inside to melt it all. It's best to use boiling water. But ask your parents for help or do this step under their supervision.
3. Pour the melted liquid into a nicely shaped container (such as a heart-shaped box with small pieces of choconai). Don't pour too much. As for why, read on. Of course, you'll want to put the thread for the wick in the container first.
4. When the original wax has cooled, pour in the melted colored crayon liquid (colored crayons come in handy here) as you did on the other side. In this way, the different colors of wax layer by layer to add, good-looking candle is made.
7, homemade wall hanging baskets
Materials and tools: two Sprite bottles, glue, carving knife, scissors.
Methods:
1. Remove the green bottom set of a Sprite bottle, cut it into a lotus shape, turn it down and glue the bottle into a base.
2. In the green bottom set intercepted 2 cm wide green ring, still set on the bottle.
3. Remove the neck of the bottle, cut out a 13 cm long and 8 centimeters wide wide band on the bottle, and a number of 3 cm wide narrow band.
4. Use a carving knife to carve a pattern on the 3 cm narrow strip? As in Figure 3, then fold these narrow strips outward and insert them into the green ring from the bottom up.
5. Take another beverage bottle and, using the bottle, cut out six 17 cm capsule leaves with scissors.
6. Nail the basket to the wall, insert the leaves and flowers, and the wall-mounted basket is made.
8, homemade cockroach capture box
Take a piece of cardboard 220 × 150 (MM).
The most important part of the capture box is the capture surface. Take a piece of plastic film, cut it to the same size as the bottom of the box, apply adhesive and lay it on the bottom of the box. Cockroaches can be caught, the key lies in the adhesive. Adhesive has two functions: one is to introduce cockroaches into the box, and the other is to stick them on the catching surface. Modulation of the lure agent: mix 40% meat powder, 50% flour, 10% soybean cake, the total amount of about 20 grams, mix well and wait for use. Adhesive is 20 grams of rosin mixed with 10 grams of vegetable oil, heated to a gelatinous state, the lure and the adhesive mixed and stirred well, that is, made of adhesive.
To mix the above paste evenly coated in the plastic film has been lined with the capture surface, and then folded inward according to the original drawing of the dotted line, and finally the tongue B inserted in the notch A.
Because of the non-drying nature of the rosin and vegetable oil mixture, the bait can be made sticky for up to a week. Place the box in a cockroach-infested area. Because the box is darker and has a bait that the cockroaches like, the cockroaches will crawl into the box and fight for the bait and get stuck to it. Sticky full, both the carton can be flattened and discarded, but also remove the plastic film, plastic film coated with bait, so that the box can be reused.
If the size of the capture box to expand, and will be slightly adjusted to the composition of the adhesive, thickening the coating can be made of paper mousetraps
Clean erasers with brushes
Write the wrong word, to use the eraser. After erasing, there are always a lot of crumbs left on the paper. Whether you use your hand to shoot or blow with your mouth, it is unhygienic and troublesome. Making a clean eraser won't be such a trouble.
Materials: large eraser, waste brush.
Tools: scissors, glue.
Methods:
1. In the eraser at one end of the dig a shallow small round holes 2. to the end of the waste brush removed, washed and dried.
3. Cut off the tip of the brush head, so that it becomes a small brush
4. Nestle the brush head into the small round hole of the eraser, and glue it
Well, the clean eraser is made. Whenever you finish erasing the eraser, you can use the brush to gently "sweep" the paper debris together, and then poured into the waste paper basket.
A very simple, the key is the idea. When I was in junior high school, I also did a small production, but also won the third prize. The key to this kind of production is to come up with good ideas, production is not difficult. I'd like to recommend you a small production of that year.
Do is a small electronic balance model, note that this is a model, can only weigh very light objects, such as two small confetti. The materials needed to make it are: a board (preferably thin, not too big), a washer, crankpin, awl, soldering iron, a few wires, two light-emitting diodes, and a battery. These materials are very good to find, light-emitting diodes if you do not have can go to the electronics market to buy, very cheap.
The production process is like this: in the middle of the board with an awl to turn a small hole, will be bent into a hook shape of a crosshair, and the board perpendicular to the small hole through the board fixed on the board, the hook can be hung on the washer can be. Then take two of the crank pins and straighten half of them, retaining only one inflection; in effect the straightened portion is the arm of the balance, and the remaining bent portion is the pallet. Do the same with the other curved pin. The two crank pins and the washer are then soldered together, with the washer in the center and the crank pin in a straight line. Then hang the washer onto the hook and adjust the distance between the hook and the board, about 3MM. Then in the two pallets under the fixed two crankpin, crankpin next to the preparation of light-emitting diode for the indicator. Set up a circuit under the board, the balance is equivalent to a single-pole double-throw switch. This circuit is then equivalent to two circuits, *** with one power supply and two light-emitting diodes. As soon as the left side sinks, the tray on the left will be connected to the pin below him, thus the circuit is on and the diodes light up; if the weights on both sides are equal, the circuit is not on and neither diode lights up.
Responders: enthusiastic users | 2010-3-12 21:17
Homemade flashlight
Specific production methods are: a waste cans (such as Lulu beverage cans) up off the end of the lid, the other end with a round hammer knocked concave. With thick corrugated cardboard rolled up two batteries, battery positive pole up, negative pole down into the can. Find a suitable plastic lid (such as the magical large roll of the lid can be fastened on the Lulu can), in the center of the lid to dig a small round hole, the size of the hole to make the light bulb inserted tightly. Insert the bulb base into the hole. Take a section of wire stripped at both ends, one end around the lamp base, the other end from the side of the plastic cover to tie a small hole through. Put the plastic cover on the can. Check that the bulb and battery are in close contact. The disposable flashlight is now ready. When you use it, press the wire from the side wall with your thumb on the unpainted weld from the can, and the flashlight will light up, and when your thumb is off the wire, the flashlight will go out, which is very convenient to use.
2, I believe you must have seen a rocket on TV! The current carrier rockets are chemical rockets, to carry their own fuel as a power source. Now, let's make our own little elastic rockets.
Materials: 1 plastic straw, cardboard, playdough, a small spring, steel cans 1, bicycle steel and a 100 × 50 (mm) board, small nails 2.
Production method:
1. From the cans cut 20 × 100 (mm) steel skin a, according to the figure at both ends were drilled ф3mm holes.
2. The door traveling car wire inserted in the board, according to Figure 2 sets into the thin steel sheet and spring, and then the end of the steel skin with nails fixed to the board, made of launchers.
3. With cardboard cut four wings fixed in the lower end of the plastic straw, so that the bottom of the formation of the "cross" shape. Finally, use playdough to insert into the top of the plastic straw to make a rocket.
Play: the rocket in the launcher on the wire, the hand press the spring steel skin down, and then release, the small rocket will automatically pop up.
In the zoo students love to see monkeys climbing trees, here to teach you to use discarded materials to do a monkey climbing toys, you will love.
3. 1 plastic straw, playdough, plastic bottle 1, pencil drawing paper.
Second, the production method
1. According to Figure 1 to take a straw with an inner diameter of about 4mm, it will be one end with a small group of playdough stuffed, and then use a small cone in the front and back of it on both sides of the line of small holes, holes and holes between the hole of about 5mmi. in the drilling, will be tilted a little bit of cone to be stuffed with the end of the Playdough, all the holes to form the same angle.
2. will remove the cap of the beverage bottle, in the center of the bottle cap drilling a slightly smaller than the diameter of the type of material straw hole, the other end of the straw tightly into the round tie, the tube around the paraffin wax sealing. 3. according to Figure 2 will be screwed tightly with the straw in the cap on the bottle, and then use the lead paper to make a slightly thicker than the diameter of the straw, about 30mm high paper tube (you can wrap the paper around a slightly thicker than the straw chopsticks, the joints with the glue sticking well! ), and put it on the straw. Then use a piece of light paper, fold it and draw a monkey, cut it down into two little monkeys, color it and stick the two little monkeys' bodies to each other, and stick them to the paper tube with their legs apart. In the same way, the pencil drawing paper folded in half, painted on the top of the canopy, cut along the contour line, coloring and then glued to the upper end of the straw, the toy is complete.
Three, play with both hands to squeeze the bottle, the straw on both sides of the small holes diagonally upward of the airflow to promote the rise of the paper tube. The monkey rises with it. If you squeeze the bottle with appropriate force, the monkey will rise slowly.
4. Materials: slender cylindrical plastic milk bottle 1, a bad ping-pong ball 1, a small plastic pill bottle 1, cans 1, cork 1, a small motor 1, 5 batteries 2, a pair of metal snap buttons, the right amount of wire, screws, nuts 2 pairs of Baidu glue.
Production method 1. In the fruit bottle waist open a 40 × 20 (mm) hatch, the front end do not cut, folded upwards. The bad ping pong balls cut in half, take the good half cover the mouth of the bottle and stick. The bottom of the cans to two cut open the reverse volume of the flat, as the case cut into two pieces of wings, installed on both sides of the hull.2. Cut a piece of thin iron 40 × 10 (mm) long, the two ends of the picture folded into 90 ° to do the bracket, will be cut off the upper part of the small plastic bottles, according to the picture with screws, nuts fixed to one end of the bracket, and the other end of the picture shown above the back of the blimp fixed.
3. Cut three oval blades 30mm long, equidistant from each other at an angle inserted in the small cork around the paddles, and then installed in the small motor rotating shaft, and then according to the diameter of the plastic bottle in the motor wrapped around a few layers of cardboard, so that it can be tightly plugged into the bottle fixed.4. The small battery loaded into the cabin, the back of the cabin drilled holes, and the battery connected to the wires through the switch with snap buttons, the motor, battery and switch connected. Connect the motor, battery and switch. Operation: the speedboat into the pool, close the snap button, the circuit is on, the speedboat will sail forward, such as the blimp traveling backwards can be the lead wire poles to the right, such as the center of gravity of the boat is unstable, can be glued to the bottom of the boat to do the counterweight.
5. Simple camera
Purpose: 1, to demonstrate the structure of the camera.
2,Demonstrate the process of taking pictures with the camera.
Materials:
Printing paper, convex lens, scissors, glue, sulfate paper.
Method:
1, make the camera body: cut the body parts from the card drawing, glue the body.
2, make the lens barrel: cut the parts, glue the lens barrel.
How to use:
1. Aim the lens at a bright scene.
2. Adjusting the lens can change the sharpness of the image on the negative.
The experimental setup of "Ping-Pong ball moving against the air current" was made. The procedure is as follows.
Required materials: a mineral water bottle with a cap, a section of about 10cm long, inner diameter of about 6mm rubber or plastic tube (can also be replaced by a waste pen), a ping-pong ball. Tools needed: hole punch, scissors, transparent tape, 502 adhesive.
Production method: scissors mineral water bottles from the lower part of the bottle cut, in the bottom of the bottle to play 3 ~ 5 diameter of about 6mm hole, the ping-pong ball into the bottle, and will cut the bottle set or bonded together, so that the bottle height of about 15cm; according to the rubber tube or plastic tube diameter, in the bottle cap to play an appropriate hole, insert the tube into the hole and stick good. As shown in Figure 1, "against the air flow and move the ping-pong ball" experimental device is produced.
Experimental demonstration: hand-held rubber tube (plastic tube), let the mineral water bottle naturally sagging, so that the bottle of ping-pong balls fell to the bottom of the bottle, through the rubber tube (plastic tube) to the bottle blowing, you will see the ping-pong balls in the airflow will be against the airflow upward movement, and finally be "sucked" in the neck of the bottle and will not be blown away by the airflow.
Principle explanation: when the air flow down through the upper surface of the ping-pong ball, due to the surface of the ping-pong ball raised, increasing the distance of the air flow, the flow rate of the air flow to accelerate, the pressure becomes smaller, so that the ping-pong ball on the upper surface of the gas pressure is less than the lower surface of the pressure, resulting in the direction of the upward pressure difference, ping-pong ball by the upward "upward lift" when the force is greater than the ping-pong ball's gravity, ping-pong ball will be Against the airflow upward movement, and finally be "sucked" in the bottle.
6. According to the aforementioned method of production of a vertical plane detector (do not want to horizontal axis), and in the lower part of a standard protractor, as shown in Figure 2.2-4. After installation on the standard platform, check whether the re-plumb line and the protractor on the 0 scale line match, otherwise should be corrected.
How to use
Place the measuring device on the plane to be measured and observe which scale line of the protractor coincides with the heavy vertical line. If the plumb line passes through the 0 scale of the protractor, the plane to be measured is horizontal. If the plumb line is to the left or right, the angle of inclination can be read directly on the protractor.
7. vacuum pump 8. atomic planetary structure model:
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9. ballpoint pen wobbling upright in front of the pen holder does not fall down, you feel strange this is a magic show The answer is no, this is actually the role of magnetic force caused.
A, the production method
1, 6 × 3 (mm) magnet 2, the old toothbrush handle 1, a small piece of plexiglass, 502 glue.
Two, the production method
1, do stand. Find an old toothbrush, with a hobby knife or small saw, cut off the bristles. (Figure 1)
2, and then sawed off the end of the toothbrush handle with a hole in the section, grinding cross-section, according to Figure 2 in the distance from the head of 25 (mm) in the place of the hairdryer heat (can also be baked on the gas stove), so that the toothbrush handle softened and bent at a right angle, and then in the bending surface of the designated location, with 502 glue to fix a small magnet.
3, cut off a piece of 40 × 50 (mm) of plexiglass, polished edges, do the base of the pen holder.
4, the good stand (according to Figure 3), with 502 glue fixed in the designated part of the base plate. Along the top of the stand magnet in the vertical line, in the base plate corresponding to the point of shallow drilling a 2 (mm) recessed holes.
5, at the top of the ballpoint pen with 502 glue on a magnet, the requirements of the stand and the pen on the magnet bonding surface of the same polarity.
6, the ballpoint pen upright, so that the tip of the pen in the bottom of the concave holes, the ballpoint pen will be wobbly stand on top of the pen.
Answer: _z_t_y_ | Level 2 | 2010-3-15 21:31
1. We know that we usually find some old batteries in the drawer, but we do not know that there is still no electricity, if you put into the electrical appliances to test is very cumbersome and can not know that it is the amount of electricity remaining. So, you can make a small checker. The method is simple as follows: use a small light bulb, very small kind (like a pendant or toy light on the hardware store are sold). Then connect two thin enameled wires to each of the lamps. The other ends of the two wires are used to connect the positive and negative terminals of the battery you want to test. According to the brightness of the small bulb, you can judge the battery power. 2. Take a broken umbrella, remove the cloth, take a wire, connect one end to a TV or radio, and one end to the top of the umbrella, which is a good signal receiver. If you want to be more professional, just wrap a few more turns of wire around the top of the umbrella. It's the cheapest and quickest way, and it's just a bit funny. 3. Place a match and a large needle from a quilt together, wrap them tightly in aluminum foil from a cigarette pack, then bend the foil over the end with the match head to seal the twist. Then put a directional tail near the end and pull the needles out to make a very simple recoil rocket. To experiment, place the small rocket on a wire stand, light a match, and heat it against the part of the aluminum foil tube wrapped with the match head. When the temperature rises to the ignition point of the match head, the matchbox in the foil is ignited, causing the surrounding air to expand dramatically and gas to spew out of the tail port at high speed. Due to the recoil effect, the bazooka then flies forward from the rack. If you wrap two matches placed head to head in aluminum foil, neither end is closed. It is placed on and heated from the center. When the matches in the tube ignite, gas is ejected from both ends and the aluminum foil tube remains on the rack, thus illustrating the conservation of momentum of the system. 4. to two of the same protractor in the center of the circle riveted together can rotate flexibly, the above protractor along the right end of the frustration of a long l cm notch, measure the angle, so that it is open and to be measured on both sides of the angle coincides with the notch indicated by the scale is the angle of the number of degrees; draw the angle, the notch is aligned with the prescribed scale, and then along the opening of the drawing of two rays on the completion of the. This protractor can also measure the angle of three-dimensional objects (such as nuts). Because this protractor is used like scissors, we call it "scissors protractor". 5. I put my classmates that year's small production recommended to you. He made a small electronic balance model, note that this is a model, can only weigh very light objects, such as two small scraps of paper. Production of materials needed are: a board (preferably thinner, not too large), a washer, crankpin, awl, soldering iron, a few wires, two light-emitting diodes, a battery. These materials are very good to find, light-emitting diodes if not you can go to the electronics market to buy, very cheap. The production process is this: in the middle of the board with an awl to turn a small hole, will be a curved pin bent into a hook shape, and the board perpendicular to the small hole through the board fixed on the board, the hook can be hung on the washer can be. Then take two of the crank pins and straighten half of them, retaining only one inflection; in effect the straightened portion is the arm of the balance, and the remaining bent portion is the pallet. Do the same with the other curved pin. The two crank pins and the washer are then soldered together, with the washer in the center and the crank pin in a straight line. Then hang the washer onto the hook and adjust the distance between the hook and the board, about 3mm. Then in the two pallets under the fixed two crankpin, crankpin next to the preparation of light-emitting diode for the indicator. Set up a circuit under the planks, the balance is equivalent to a single-pole double-throw switch. This circuit is then equivalent to two circuits, *** with one power supply and two light-emitting diodes. As soon as the left side sinks, the tray on the left will be connected to the pin below him, thus the circuit is on