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 Making a Solar Car

What You Need: How to make a solar car

2 solar cells

2-4 alligator clip leads

Rubber bands

Small electric motor (get one with a motor pulley)

For the car body: cardboard milk carton, water bottle, cardboard

For the wheels: plastic bottle caps, toy wheels 

For the axles: Stiff wire 

Straws or eye screws to mount the axles

 

What You Do: 

1. Choose a material for the car body. 

2. Use a nail to poke a small hole in the centre of your wheels. Make sure the stiff wire or wooden skewers you use for axles fit in the holes tightly. Take an extra cap and cut off the sides, leaving just the top part, which usually has a small inner rim to help keep the bottle from leaking. Glue this cap to one of your wheels. You have just created a pulley for your driving wheel; the inner rim of the extra bottle cap will support your car's drive belt.

3. Now, mount your axles onto the chassis. Depending on what your chassis is made of, you can thread the axle through eye screws mounted on the bottom. Another easy method is to tape straws on the underside of the chassis and thread the axles through them. Mount the motor with glue or tape it in between a small frame of wood or cardboard blocks.

4. Use clear plastic tape to attach the two solar cells together side-by-side; then connect them in a series circuit using the alligator clip leads. Connect the positive terminal of one cell to the negative terminal of the other. Connect the remaining terminals to the motor. If the motor spins the wrong way, switch the leads where they connect to the motor. Once it's connected properly, you'll probably want to use to tape to help keep the wires under control.

5. Mount the solar cells on the chassis at an angle where they will receive the most sun. Take your car outside to a sunny sidewalk, connect the drive belt, and watch it go! 

Taken from: www.hometrainingtools.com

 

How to Make a Solar Bottle Bulb 

Where?water bottel in a box

1. Decide which area of the home/room will be the best place to add the bottle bulb. 

2. Identify any vulnerable areas inside the structure where puncturing the ceiling could cause structural issues. 

3. Consider if you can install multiple solar bottle bulbs. 

Get 

1. Pick up empty plastic water bottles. Remove the label and thoroughly wash the inside and outside of the bottle. Keep the bottle cap.

2. Pick up a gallon of distilled water and a gallon of bleach. The water acts to scatter the light, and the bleach prevents algae from growing inside the bottle.

3. Grab household industrial sealant as you will need to seal the bottle to sheet metal.

4. Purchase sheet metal--enough to surround the bottle and lay along the top of the roof, and pick up a small handsaw.

Design

1. Measure the circumference of the top 2/3 of the bottle and transfer the measurements to your structure’s roof.

Cut a hole in the roof using your handsaw.

2. Transfer the same measurements to the extra piece of sheet metal. Draw a circle for the bottle measurements and then draw a large square around the circle.

Cut out the square and the circle on the sheet metal. Test placing the bottle through the circular hole. The bottle should fit snugly, allowing 2/3 of the bottle to hang down through the bottom of the sheet metal.

3. Fill the bottle almost to the top with distilled water. Don't overfill as you will need to add bleach.

4. Top off the bottle with bleach, approximately 3 tbsp. allow the bleach to permeate through the distilled water without shaking the bottle.

5. Add the cap to the bottle and tighten.

6. Slide the bottle into the sheet metal and add sealant around the base of the bottle. Make sure you add a liberal amount of sealant in order to avoid having rain or other outside elements escape through the hole.

7. Drop bottle through the hole in the roof and allow the sheet metal to keep it in place.

Taken from: www.instructables.com

  

Homemade Thermometer 

What You Need:

Modelling clay/Prestik

Red food colouring

Water

Clear straw

Rubbing alcohol

Clear plastic bottle

Thermometer (optional) 

What You Do:

1. Pour equal amounts of tap water and rubbing alcohol into the bottle until it's a quarter full.

2. Add a few drops of red food colouring, and shake the bottle to mix it.

3. Insert the straw into the bottle, not letting it sink to the bottom.

4. Wrap modelling clay around part of the straw and the opening of the bottle to make it stay. Let part of the straw stick out of the bottle. The clay should be tight around the straw and cover the bottle mouth, but make sure to leave the top opening of the straw uncovered.

5. Test the thermometer! Have your child put her hands around the bottle. What happens to the mixture when her warm hands are on it? 

What's Going On?

When the alcohol and water mixture gets hot, the mixture expands, sending the water up the straw. How hot would it have to be for the water to come out of the straw? 

Taken from www.education.com

  

Climate change in a bottle 

Material 

Two small plastic bottles (about half a litre), empty, label removed, identical

Marker to label the bottles

Black tape

Two thermometers

Vinegar

Baking soda

One glass bottle (small)

One large and one small funnel

One balloon for CO2

Data sheets

Timer (for whole group)

One lamp between the bottles or two lamps (one by each bottle)

Optional: scissors and soil and duct tape 

Set-Up 

1. Take two plastic bottles – make sure they have caps! 

2. Check to make sure they are dry inside – water will absorb CO2 and change our results!

3. Label one bottle A (air) and the other C (CO2).

4. Take the cooking thermometer and pierce the side of the bottle, close to the top.  

5. Insert the cooking thermometer through the small hole until it is stable.  Make sure you can see the temperature reading.  Also, make sure the end of the thermometer is in air – NOT touching the bottom or side of the bottle. 

6. Put tape around the bottle and the opening where the thermometer goes into the bottle.  Try to seal the opening as much as you can to avoid CO2 leaking out later.

7. Take the glass bottle and pour 50 ml of vinegar in it through the big funnel.  Take a balloon and pour 1 teaspoon of baking soda in it through the small funnel.  Carefully place the balloon over the mouth of the plastic bottle so that it is air-tight and the baking soda falls into the bottle.  The baking soda will react with the vinegar, producing CO2, which will fill the balloon.  Shake the bottle a bit more to get all the CO2 you can. 

8. When the balloon is full, take it off the bottle top and pinch it shut. 

9. Quickly transfer the balloon to the plastic bottle you’ve decided will contain extra CO2, and squeeze gently so that the gas transfers to the soda bottle.  The CO2 will sink to the bottom of the bottle and push out ordinary air. Remove the balloon and put the bottle cap back on so that the gas is trapped inside!

10. Place the lamp in front of the two bottles, making sure it is at the same distance between each bottle.   

Experiment 

1. Run one experiment together.  Give each student a task from the set-up and running experiment sections so they each have a role to do in both.

2. Designated students should take the experimental material and set it all up according to the instructions.

3. Students set to measure temperature and those set to record temperature should take their places.

4. Turn on the thermometers and let them stabilize.  Set them to Celsius. They should show temperatures that are roughly the same. If they don’t, give them more time and if they are still different, write down what the difference is.  

5. Wait until the timer is ready, and everyone countdown from 10.

6. Turn on the lamp! At the first minute, the teacher will ring a bell, and everyone will take the first measurement.

7. Take measurements every minute for fifteen minutes – try to be as accurate as possible. 

Taken from: www.teachingchannel.org

 

How to make a pinwheel wind turbine 

What You Need:

Cardstock

Pencil with eraser

Straight pin or thumbtack

Small electric motor )

Alligator clip leads or insulated copper wire

1.5-volt bulb and bulb holder 

Strong fan (standing or box fan)

What You Do:

Pinwheel 

1. Cut a piece of cardstock into a 4' square. 

2. Use a ruler to draw diagonal lines from corner to corner. Make a small mark along each line 3/4 of an inch from the centre of the square.

3. Cut along the diagonal lines toward the centre until you reach the 3/4-inch mark.

4. Fold the corners marked with circles on the pattern into the centre and staple the layers together. When all four 'blades' are folded in, stick a straight pin or thumbtack through all the layers at the centre. Push the pin through the eraser on the pencil to finish the pinwheel.

5. Hold the pinwheel in front of a fan and watch it spin. The currents of air coming from the fan catch the curved part of the blades, causing them to spin.

Generator 

1. Remove the pinwheel from the pencil and punch the shaft of the motor through the centre. (Try putting a couple strips of masking tape on the back of the pinwheel before you punch it through - this will make a tighter fit on the motor shaft.) If your motor came with a little cap for the end of the shaft, put that on to hold the pinwheel in place. If you don't have a cap, use a piece of clay or cork.

2. Use the alligator clip leads to connect the motors wires to the light bulb.

3. Now hold the motor/pinwheel close in front of the fan again. Does the bulb light up? Look closely - you should at least see the filament begin to glow. The brightness of the bulb will depend on how much voltage your turbine is producing, which can change with the size of the pinwheel and the strength of the fan. 

What Happened?

When you attached the motor to the pinwheel and put it in front of the fan, you transformed the motor into a generator, which converts mechanical force (the spinning of the pinwheel) to electricity. It does this with the help of a magnet inside the motor. When you connected the wires of the motor to the light bulb, you made a complete electrical circuit, allowing the electricity to flow from the motor through the bulb and back again.

One way to measure power is in volts. A volt measures the amount of electricity flowing through a circuit. The faster a generator spins the more volts it will produce. With our simple wind turbine, a smaller pinwheel will produce more volts because it can spin faster. To fully power the bulb, your turbine would need to produce 1.5 volts. If the bulb just glows dimly, it means the turbine is producing less than 1.5 volts.

Real wind turbines have very large blades, so they have gear boxes that increase the rotational speed (how fast the shaft spins). For example, the main shaft might turn only 22 times per minute, but the gears in the gearbox can use that power to make a smaller shaft turn up to 1500 times per minute, creating a lot more voltage!

Taken from: www.hometrainingtools.com

 

Making a water turbine

Materials

2-liter plastic soda bottle

Ruler

Marker

Craft knife 

Scissors

2 corks

1 wooden barbeque skewer

Sewing thread (16 inches)

Small objects to lift (an eraser)

Sink

Duct Tape

Large Funnel

Paper clips 

Procedure

1. Using your marker and ruler, measure and mark a few dots 6 cm up from the bottom of the bottle. Connect your dots and cut off the bottom using the craft knife.

2. Measure an 8cm section from the cut part of the bottle. Cut out this section so that you have a cylindrical section of plastic.

3. Cut four 2 cm-wide strips from the 8cm section with your scissors. Cut these strips in half so you are left with eight curved strips that measure 4 cm by 2 cm.

4. Draw 8 evenly spaced lines lengthwise on the cork, and make slits along each line with your hobby knife. Making sure that the plastic pieces all curve in the same direction, slide each 4 cm by 2 cm plastic piece into its own slit. Why do you think it’s important that the strips all curve in the same direction?

5. Unfold two paperclips and flex one end of each to create a small loop. These paperclips will act as supports for the water wheel’s axle

6. Affix your supports on opposite sides of your plastic funnel using your duct tape.

7. Cut the skewer in half and poke each half into one side of the wheel cork. Guide each end through a loop on your paper clip support. Make sure your paper clip’s loops are loose enough to allow the wheel to turn freely.

8. Insert one of the skewers into the other cork and tie thread tightly around it. Tie the loose end of the thread to a weight or other small household object.

9. Place your completed water wheel under a gentle stream of water in your sink. Slowly run water over the wheel so that the plastic pieces on the cork catch the falling water and turn it into mechanical energy

Taken from: www.hometrainingtools.com

 

Paper mache bowl 

What you need

plenty of recycled paper, for example: lolly wrappers, coloured paper, coloured foil, envelopes, comics, newspaper, magazines, wrapping paper

paint and paintbrushes

newspaper ripped into small pieces/ strips (4-5cms wide and at least 15cms in length).

a balloon

a wide cup/ small bowl

Vaseline

scissors

homemade glue 

paintbrush

strip of card, approx. 2cm x 25 cm

stapler

masking tape

Activity

To make bowl:

Lie newspaper out on the table and create a work area.

Blow up the balloon and fasten with a knot.

Spread plenty of Vaseline all over it.

Sit the balloon in the cup with the knot facing into the cup.

Brush over some paste with the paintbrush on the top half of the balloon.

Cover the top half of the balloon (that is covered in paste) with strips of newspaper.

Make sure the newspaper is wet entirely with glue – add more if required.

Paste the strips horizontally and vertically as this will strengthen the bowl.

If you end up with an air bubble or glue lump, tear a smaller bit of newspaper and press it firmly over it, to smooth it out.

Cover the ends that haven’t been glued down properly with glue.

Add at least six layers of newspaper and glue to the top half of the balloon.

Leave it to dry in a warm, sunny place for the day.

When dry remove the newspaper mould from the balloon.

Trim off the rough edges, using scissors.

To make a base for the bowl:

Turn the bowl upside down.

Make a loop / circle with the strip of card, and staple in place.

Attach the loop to the base of the bowl with masking tape.

Paste on some glue and cover it with newspaper pieces / strips.

Once the bowl and base are completely dry it is ready to be decorated.

Essentially you are decoupaging (paper collaging) the bowl.

Cover it entirely with your selected paper and glue.

Paint if you desire.

Decorate until all of the newspaper is covered with colour and patterns.

Notes:

Wallpaper paste will work well for this activity. You can buy this from hardware shops. Put about a tablespoon in a bowl. Add water and mix until it binds together. It should be thick enough to brush onto a surface.

Alternatively to using a balloon, mould your bowl around a plastic bowl from your  

Taken from: www.kidspot.com

 

How to Propagate Plants

 Follow these 5 easy steps:

1: Pinch off the tip portion of a stem only.  You don’t want to use another parts below this, as the newer growth at the tip of a stem will produce better roots.  You don’t need any more than one inch of stem, depending on the plant.  Cut between two nodes, which is the part where a leaf meets the stem.

2: Remove lower leaves, leaving only a few on the tip.  Set aside for at least a day to allow the stem to callous, or heal over.  This will allow better root formation.  You can also use the leaves to make new plants.

3: I like to stick the new cuttings in a flat when allowing for time to grow roots.  I use a traditional peat/perlite potting mix for houseplants.  I never use cactus mix as it is too sandy and have found that my succulents have grown better in the general potting mix anyway.  It looks pretty too.

4: Once they have developed roots, it’s time to plant them into your frame, container or terrarium. 

5: Once planted, little care is needed.  Keep in a low light area for about two weeks before moving them to receive sunlight.  Water when the soil dries out. 

Caring for your Succulents:  If your new plants become “leggy” pinch off the tips and start a new plant.  The original stem should develop smaller shoots. I like to keep my creations pinched back and have a continuous supply of baby succulents.  I never know when I need a little gift for something.  These little treasures make great gifts when planted in small terracotta pots. 

TIP:  Want to increase the variety of your collection of succulents?  Share this post with friends, and have each of you purchase a succulent plant, propagate, and hold a plant swap.  Soon you will end up with many different varieties.

 

Pizza box solar cooker

You will need:Pizza box top removed with foil

1. Large pizza box

2. Aluminium foil

3. Black construction paper

4. Pencil

5. Box cutter/scissors

6. Ruler 

7. Plastic wrap or large transparent plastic bag

8. Clear tape

Method:

1. Make sure the pizza box is clean

2. Draw a square on top of the pizza box, 2.5cm in from the edge of the top

3. Use box cutter or knife to cut out three of the four sides

4. Bend the uncut side of the square to create a flap that stands up

5. Cut a piece if aluminium foil big enough to cover the inside if the flap and secure with tape

6. Cover the bottom of the pizza box with foil and secure it with tape

7. Line the bottom of the pizza box with black construction paper

8. Cut two pieces of plastic wrap that are the same size then wrap the inside and outside of the pizza box; making a window

Tips:

1. Use a black dish to have the dish absorb heat

2. The aluminium foil reflexes the rays of the sun

3. The plastic wrap insulates the heat inside the box

4. Black paper absorbs the heat from the sun

5. The oven should be at 94®C degrees to cook

What the solar cooker can do:

The pizza box can heat small meals like a slice of pizza and melt cheese or even warm left over plate of food.

It can cook an egg in one hour or a vegetable stew the whole day.