Tag Archives: physics

#TryThisTuesday: Chicken Sounds from a Cup!

Try This Tuesday, , , , , , , ,

This week we are going to make chicken sounds from a cup!

You will need:img_4715

  • plastic cup
  • string
  • paperclip
  • paper towel
  • scissors
  • water
  • pin

 

 

 

First put a hole in the top of your cup. We found it easiest to push a pin through and then make the hole larger with scissors.

Cut a piece of string that is about 20cm long and put it through the hole in the cup.

Tie the top end of string to the side of the paper clip.img_4716

Wet the paper towel. Hold the cup in one hand and wrap the paper towel around the string near the paper cup. Squeeze the string and pull down in sharp jerks to make the chicken noise!

The Science

Sound travels in waves, which cause particles to vibrate and causes the sound. The vibrations from the string would normally be almost silent without the cup.

When you add the cup it amplifies the sound and makes it much louder. This is because the cup is a solid object, and there are lots of closely squashed together particles in a solid object for the sound waves to hit and vibrate. The more vibrations the LOUDER the sound.

 

#TryThisTuesday: Cork Balancing

Try This Tuesday, , , ,

Today we’re challenging you to balance a cork on its round side, on the very end of your finger, whilst keeping your finger straight. 20161018_163129_resized

Could you manage it?

It’s quite tricky, but here’s a hint: two forks could help you out.

20161018_163159_resized

Have you figured it out yet? Remember the cork must be balanced on your finger not the forks.

The solution is to stick the forks into either side of the cork. You should then be able to easily balance it on the end of your finger.

20161018_163223_resized

There are two reasons this works. Firstly the forks add weight to the object you’re trying to balance. Because the ends of the forks hang below your finger, it lowers the centre of mass so that it sits underneath your finger, increasing the stability.

Secondly, adding the forks extends the object. By making it longer, the centre point is also stretched making it easier to locate so easier to balance the object. This is why tight-rope walkers often have long poles to help them balance.

Image result for tight rope walker

#TryThisTuesday: Easter Eggsperiments

Try This Tuesday, , , , , , , , , ,

As Easter is coming up we’re treating you to four experiments instead of one this week! And a little video showing Ellie and Clare demonstrating each of them (or at least attempting to!)

1. Hard-boiled Egg Test

Our first eggsperiment requires a hard boiled egg so we’re going to show you how you can test if an egg is hard boiled or not.

Lay a hard-boiled and a normal egg flat on their sides and spin them. Put your finger on the eggs to stop spinning them and then let go. The one that starts spinning again is the raw egg.

This is all due to momentum. When you spin the eggs you spin their insides too. In the hard boiled egg, the insides are fixed to the shell so it behaves as you would expect. In the raw egg the insides continue to spin after you’ve stopped the shell. When you let go, the momentum of the spinning yolk carries the shell and the whole egg starts spinning again.

 

2. Egg in a Bottle

Now we know which is our hardboiled egg, we need to peel it for next experiment. This one requires a glass bottle, a match and of course, the egg.

If we place the egg on top of the bottle it doesn’t look like it’s going to fit in. But if we light the match and drop it into the bottle then after a second place the egg on top, the egg will squeeze into the bottle.

The match heats up the air in the bottle, causing it to expand slightly. The egg creates a seal so more air cannot enter. As the air cools inside the bottle it decreases the pressure and forces the egg into the bottle.

 

3. Naked Bouncy Egg

To make a naked bouncy egg you will need an egg, white vinegar and a beaker. Place your egg in the beaker and pour in enough vinegar to cover the egg. Leave you egg here overnight.

The egg shell is made mostly of calcium carbonate, this reacts with the acid in the vinegar and dissolves to leave a naked egg. It also produces carbon dioxide gas, so as your egg is soaking you may see little bubbles of CO2 forming around it.

After a day, carefully remove you egg from the vinegar and wipe away any remaining shell. You should see that it’s now quite rubbery and bouncy as well.

 

4. Bouncy Elastic Egg Drop

For this final eggsperiement you can use your bouncy naked eggs but we’re cheating a little bit and using rubber eggs. For this you will need to take two rubber eggs and join them together with a piece of elastic or a string of elastic bands.

When you hold your eggs next to one another and let go they both hit the floor at the same time as you might expect. But what do you think will happen if we just hold the top egg and let the other hang below it, which will reach the floor first when we let go?

Gravitational acceleration is the same no matter the weight or mass of an object, but when we add elastic between the eggs, this adds an extra force that speeds up the drop of the higher up egg as the elastic pulls them together.

 

#TryThisTuesday: Skipping Stones

Try This Tuesday, , , , , , , , , , ,

During our time as STEM Ambassadors, we’ve visited several beaches together. From Newcastle in Northern Ireland to Clear Water Bay in Hong Kong and even beaches closer to home in Whitley Bay and Tynemouth, we always ended up skipping rocks somewhere!

But how do we do it!? Why don’t the rocks just fall into the water?

Skipping rocks in Whitley Bay

The key is to get a nice flat rock and throw it quickly at the right angle. The large surface area allows the stone to bounce off the water’s surface.

You need to throw it fairly hard to give it enough speed to gain momentum before it hits the water. When the rock hits the surface of the water it pushes the water down whilst the water pushes the rock up. If the force pushing the stone up from the water is greater than or balances the weight of the stone then it will bounce on for another skip rather than sinking. This is why it helps to have a nice small stone.

20170401_161404

It is also important to get the right velocity. Velocity is the speed of something in a give direction. So we have the speed covered, now for the direction. Scientists have discovered that the optimal angle at which the stone should hit the water should be around 20 degrees. As you probably won’t be able to measure this on a causal day trip to the beach, just aim to throw the stone sideways rather than up or down.

Hopefully you’ll manage more than my measly two skips. Try beating the world record of 88 skips in a row!

Will skipping rocks in Northern Ireland
Will skipping rocks in Northern Ireland

Exoplanet discovery

Articles, , , ,

Recently NASA have found the TRAPPIST-1 Solar System (named after the TRAnsmitting Planets and Plantisemals I Small Telescope). It is 40 light years away in the constellation of Aquarius and has seven Earth size Exoplanets (planets that orbit a star that isn’t the Sun) that have the potential to support life.

This is a big discovery as it is the largest amount of Earth sized planets ever found around a single star and it might help in the search for life on other planets. trappist

How did they find the TRAPPIST-1 Solar System?

  • The Star in the centre of the solar system glows brightest in infra-red light which can’t be detected by the human eye
  • The infra red light was detected by an infra red telescope called the Spitzer. This telescope is in space and follows the orbit of the Earth.
  • The radiation (light) detected from the TRAPPIST-1 star would periodically dim and then brighten again; this could show that a planet could be passing in front of the star.
  • The dips in light were not always the same amount, showing that there were actually seven exoplanets orbiting the star.
  • NASA used the dips in radiation to calculate the size of each planet in the solar system.
  • Space in between the dips in radiation means they can work out how it takes for a planet to orbit the star.
  • The planets were found to be very close together with orbits that interfere with each other due to gravity.
  • They used the estimated size of the planets to work out what the density of each planet is, to work out what the planet might be made of.
  • All seven planets may be suitable of supporting liquid water, with three in the habitable zone capable of having oceans.
spitzer
The Spitzer Telescope

What next?

It’s really rare to find this many planets that may support life in one solar system so its important to find out more about them. NASA are going to use transmission spectroscopy to study the composition of the seven exoplanets. This is a technique that gives information about the chemical composition of a planet and whether a planet has an atmosphere.

They are using more telescopes to study some of the other ultracool dwarf stars (like TRAPPIST-1), to see if they also have exoplanets that could support life.

#TryThisTuesday: DIY Sci-Fi Laser Sound

Try This Tuesday, , , , , , , ,

This week we will show you how to create sci-fi laser sound effects using a slinky and a cup.

16880217_10210650089140843_1066614229_o

The first step is to try and listen to the noise a slinky makes on its own by moving it up and down so the bottom of it bounces off the floor as shown in the picture below.

16901523_10155289747075695_1891472516_n

The next step is to place the cup in the top of the slinky as shown below and try the same movement.

16833383_10210650212743933_948670898_o

The Science

Sound is actually particle vibrations and travels in waves. This means it relies on particles colliding to transfer the sound energy. In a gas such as air the particles are really spread out which means they are less likely to collide. In solids the particles are much closer together which means the particles collide a lot more and the sound energy is transferred more effectively.

partic

This is why the sound is much louder when the sound waves travel through the solid cup as opposed to the air. Rumour has it that they actually used this same technique to make the laser sound effects in the original Star Wars movies back in 1977.

Engineering Education Scheme

Articles, , , , , , , , , , ,

This week we’ve been helping out with the Engineering Education Scheme. Lots of year 12 students from the local area have been working with industry to come up with a project based on real scientific, engineering and technological problems. The students have come in and had a chance to work in the engineering laboratories and workshops that university students and researchers would use. After lots of problem solving and hard work, they presented what they had done so far. These are just a selection of some of the projects.

Mechanical Engineering – Lifting

This group was working on creating a lifting mechanism for a heavy item/box. The current method of lifting isn’t very good as its centre of gravity is in the middle so it wobbles when they lift it. They created a design with a cradle for the box which spreads out the centre of gravity. It is more stable and quicker to lift, saving the company time. The use of shackles mean the box can attached by hand, no tools are needed, again saving time.

img_4247

Mechanical Engineering – Shield

A mechanical engineering group created an extendable shield. This is important for keeping people safe in war. In general all shields appeared to be really big or small, but there were none that could adapt to the situation. Use of cogs allowed the shield to be extended or retracted, solving the problem.

img_4243

Electrical and Civil Engineering – Solar Power

The brief from WSP Global was to provide renewable energy through use of solar panels to the 350 people who work in the office. The students made a to scale model of the office based on blueprints and used a fixed angle light (as the sun) to look at the shading on the roof of the building. They also ran computer simulations to look at which areas would capture the most sun.

img_4242

Civil Engineering – Leisure Centre

The brief was to design a leisure centre on land near to St James Football Park. There were lots of problems to be overcome in the design. The centre was to be built on top of an old mine shaft, which might mean the building would fall into the ground. They calculated that it was too expensive to fill the land underneath with concrete, so calculations had to be made for how heavy each part of the leisure centre would be.

img_4249

Marine Engineering – Underwater vehicles

This marine engineering group was helped by engineers from BAE systems. They looked at making an underwater unmanned vehicle. They had to do some problem solving with getting the submarine to sink, working out the exact amount of weight required to make it neutrally buoyant. They used electromagnets to power the vehicle.

img_4240

Marine Engineering – Underwater pipes

This group worked with GE oil and gas looking at using flexible pipes underneath the seabed. They compared two different materials; thermoplastic and thermoset.  They did lots of tests, looking at things such as compression (squashing) and torsion (twisting) to find out its properties. They also looked at factors such as the price. Testing found that it was really important that there were no faults in the thermoplastic as it broke a lot easier. Underwater pipes are really important for transporting things like oil and gas.

img_4245

 

#TryThisTuesday: Book Pulling

Try This Tuesday, , , , , , ,

You’ve probably got exams coming up, maybe you’re supposed to be revising now, chances are you’re surrounded by textbooks. If so here is a quick little experiment you can try.

All you need is two large books with lots of pages, around 200 or so.

20170110_142811
Start by interleaving the pages one on top of the other to sandwich the books together, like so:

This doesn’t require any kind of glue or tape but the two books should now be securely stuck together. Challenge your friends to try to pull the books apart – no matter how strong they are, they won’t be able to do it!

So if there’s no glue, why is this? It’s all because of friction. Friction is a force that occurs when one object moves over another – it is the resistance that is felt. When you try to pull the books apart there is friction acting on each page opposing the movement. If you consider there are over 200 pages, this force is multiplied and so becomes super strong!

When you pull the books the pulling motion squishes the pages in the middle with a greater force, this in turn makes the force of friction greater as it acts to oppose this force. So the harder you pull, the more difficult it is to separate the books!

Our top STEM jokes!

Listicles, , , , , , , ,

It’s nearly Christmas and that means it’s time for awful Christmas cracker jokes. Hopefully our favourite STEM jokes will be a bit more funny! Scientific explanations are underneath each one.

joke7

Neutrons make up the middle (nucleus) of atoms and don’t have any electric charge, unlike protons (positively charged) and electrons (negatively charged).

joke5

Light is made up of small particles, these are called photons. Therefore, a photon is travelling light.

joke6

The chemical symbol for oxygen is O and potassium is K.

joke4

H2O is water, but H202 is hydrogen peroxide. Hydrogen peroxide would cause chemical burns and choking if it was drunk.

joke3

Atoms are very small and make up everything, including us.

joke9

Schrodinger’s Cat is a thought experiment in physics, where a cat is kept in a box with a radioactive source and poison. Until the box is opened, the cat can be assumed to be both dead and alive.

joke1

Helium is a noble gas, this means it is doesn’t react with other elements so is inert.

joke10

Extrapolation is when you estimate what the result may be beyond what you measured. The joke is that some people can’t extrapolate from data so can’t work out the end of the joke

joke2

Binary is a way of using two different symbols, 0 and 1, to represent any number, this is often used to create code for computers. 10 in binary is the same as writing 2. Therefore, there are two types of people, those who understand binary and those who don’t.

joke12

If an atom loses an electron (a negatively charged particle) it will become positively charged.

joke11

If time travel is ever invented, it doesn’t matter when as you can just travel back in time with the time machine.

jokes8

Anti gravity is a place or object that is free from the force of gravity, so would float around.                       joke13

This is a play on words, as the atmosphere in a restaurant is how you feel when you are there, but in science terms the atmosphere is a mixture of gases that surrounds the Earth. The moon has a much thinner atmosphere than the Earth and was originally thought not to have one.

 

#TryThisTuesday: Pop or not?

Try This Tuesday, , , , , , , , , , ,

Today we will be experimenting to see what happens when you put a lighter or a flame underneath a balloon filled with two different states of matter: air and water.

popornot

You will need two balloons, some water and a lighter

  1. Blow up one of the balloons with air and tie it up.
  2. Fill the other balloon with a little bit of water, blow it up the rest of the way and tie it up.
  3. Hold the lighter under the balloon with the air in it and see what happens. Be careful as it should pop!

    Balloon with air in
  4. Light the lighter under the balloon with some water in it, be careful to hold the lighter under the part of the balloon where the water is. The balloon won’t pop!

    Balloon with water in

The Science

This happens because water can absorb heat a lot easier than air and is a better conductor of heat. Water keeps the heat away from the balloon. This is called its ‘heat capacity’ and is why water is often used to cool things down in places such as power plants. The air is not very good at absorbing the heat, so the balloon heats up and pops!