Weather gadgets are so much fun! In Weather 101, we made a thermometer and a weather vane (which, if you remember, tracks the direction the wind is coming FROM!). There are more cool weather gadgets to discover and in this blog post we explore two more:
- an anemometer can be used to track how fast the wind is blowing and,
- a barometer to measure barometric pressure which is the pressure in the atmosphere around us.
Make an Anemometer
- 5 small light paper cups
- 2 straws
- One pencil with an eraser
- Sharpened pencil
- Lump of modeling clay
- Paper plate
- Long straight pin
- Glue or tape
- Use the sharpened pencil to push a hole through the top portion of 4 of the cups, but all at the same place. Go straight through the cups to the other side at about the ¼ way mark.
- Mark the middle point of both straws using a ruler.
- Push a pencil through the middle of the bottom of the 5th cup. Wiggle it around to make the hole a little larger. Push a pencil into and across the midpoint of that cup and push one of the straws through it. Then just below that push the pencil through the midway point from the perpendicular direction. And push another straw through there.
- Push the cups onto the 4 ends of the straws all facing in one way around the circle.
- Glue or tape the cups to the straws.
- Push the straight pin into the center points of both straws and into the eraser of a pencil.
- Push the pencil bottom into a mound of clay.
An anemometer measures the wind speed… but how? While our anemometer isn’t measuring the actual wind speed (miles per hour) it does tell us if the wind is moving fast or slow (or if there is any wind at all!) The moving air hits the cups and gets trapped inside. It doesn’t slow down very much, it just keeps pushing the cups as it moves. If the wind is moving fast, the cups will spin fast; if the wind is moving slowly, the cups will spin much more slowly.
Make a DIY Barometer
- Large mouth jar, cup, or can
- Balloon that has NOT been blown up already
- Rubber bands (2)
- 2 straws or a chopstick
- Large piece of stiff paper like cardstock
- Silicone glue (like rubber cement)
- Cut the open side of the balloon off – close to the mouth.
- Open it up and place it over the mouth of the jar, cup, or can
- Hold it with the rubber bands around the rim.
- If using a straw, squeeze the end of one of the straws so that it fits inside of the first straw to make a longer “pointer”
- Cut the end of the inserted straw into a pointer shape (triangle)
- Glue the end of the original straw to the center of the balloon. And use tape to hold it there until it dries. (could be a few hours)
- Fold the cardstock in half using a hotdog fold, or you can stand it up next to your barometer and allow the pointer to indicate if the pressure is going up or down.
A barometer measures air pressure. Air pressure is how close or how far apart the air molecules are from each other. Changes in air pressure can be caused by many things like the temperature in the air or how far away from the Earth’s gravitational pull you are! When the molecules of air are very close together it is a higher pressure and when they are further away from each other it is a lower pressure. Your barometer can detect the changes in air pressure and you can track weather data over time to see those changes!