Jaydeep (7) asked “Why do sponges absorb more hot water than cold water?””

Thanks team. I agree with you I don’t have an answer to Jaydeeps question. I think the best I can do is try to carry out an experiment to test the observation that you have made.

I would need a sponge (natural or manufactured), a fixed amount of water and a way of drying the sponge. If we are going to do a fair test the sponge must be the same for both the hot water and the cold water test. It also must be in the same condition (preferably dry). I would also need to be aware that you should weigh the water, the weight of hot and cold water must be the same. As water is heated the volume gets bigger.

Jaydeep …maybe you could also try the experiment above and see whether a sponge does absorb more hot water than cold water. You could let me know the result by telling me your result in the comment box below.

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Luisa 9 asks “How did the first humans appear?”

Thank you Luisa for your second question.  Here are my friends thoughts about how humans appeared.

Thanks team, Luisa let me add some more details.

My friends are correct, it is thought that the first life appeared millions of years ago. The life that formed was not at all like the animals and plants that we see around today. It was very, very small. So small that we would have needed a microscope to see it.  Over the next thousands of years that life changed (we say it evolved) and it reproduced. Sometimes when it reproduced mistakes were made and bigger forms of life were formed. Eventually a mistake in the reproduction led to the first plant (a moss) being formed.

Over the next thousands of years further mistakes were made and  the first animal was born. From then onwards the evolution of animals and plants continued…….UNTIL …..again many thousands of years ago the first apes evolved. The apes continued to have babies and further mistakes were made …… the baby apes walked upright, their brains were bigger, they had less hair, all small changes but over thousands of years small changes can become big changes. The result was that humans were formed and you, me and everybody else are the result.

Things haven’t stopped ….changes (evolution) continues …..we might be very different in many thousands of years time.

Hope this helps. Not happy about something, then ask another question.

Unknown (age 7) asked – “Why is the sky blue?”

Hello unknown. I would not normally answer questions to an unknown questioner, but, as it it such an interesting question I asked my friends for some comments.

You are right. Where does the colour come from? It was in 1671 that the famous scientist, Newton, discovered that white light was a mixture of different coloured lights. He did this by passing white light (the light from the Sun) through a glass prism. Look at what he got……….

Later it was found that some of the blue light in the Sun’s light had difficulty passing through the Earth’s atmosphere. this blue light was scattered as it passed through the atmosphere therefore giving the sky a blue colour.

Some of the blue light still got through and appears as part of the white light in the prism experiment and also in the rainbow. In the rainbow the drops of rainwater act as small prisms.

Hope this makes sense. if you want to give your name please let me know in the comment box.

(amended 21/9/18 – raindrops as prisms added)

“What does “eco” in ecosystem mean?” asks Austin (8)

I will just add a few words myself. Thanks for your input.

I like the idea of an ant’s nest being an example of an ecosystem. The nest is ‘everything’ it’s a home, a place to live and to work from, a creche for baby ants, a food store, a food production place, a protective environment, maybe an ant hospital, and lot’s more. It is an ecosystem.

The word ‘eco’ also combines with ‘logy to form ‘ecology’. This is like the word ‘bio’ combining with ‘logy’ to form ‘biology’.  The word ‘logy’ is a word which originally described lots of learning.

I will stop now. For an eight year old I think everything gets very complicated. I very much like the ant’s nest described as an ecosystem.Maybe you could let me know of other ecosystems?

STOP

“How does speed affect the energy of motion during a collision?” asked Damián Muñoz (9)

Thank you for your question Damian. I asked my friends about it and they had the following thoughts.


Sorry Damian it doesn’t really answer the question you asked. They have just presented you with more questions.
Let’s look at what they said.

Firstly energy is about work. The Energy or Work associated with a moving car is its movement. This type of energy is called Kinetic Energy. We could change the car’s Kinetic Energy by making the slope steeper (move the slope up a rung). It will make it go faster.

How do we measure the energy it is gaining as it moves faster and faster down the slope? Yes it does go faster while it is on the slope (we say that it is accelerating). Remember it starts with no energy at all (not moving). When it reaches the bottom of the slope it is going at its fastest speed.

We could measure the energy by seeing how long it takes to stop moving when it reaches the bottom of the slope. Try it. Make sure the test is fair. Fairness is very important in science investigations.

Alternatively you could involve it in a collision at the bottom of the slope…..say some cardboard or paper and see how far the car can push the shape it collides with. That would be another way to measure the ‘work’ that the moving car could do.

Damian, think about it. Experiment, and let me know how you got on.

Science Master

Hamish Astra (11) asked “What are electrons and protons and neutrons made of?”

What a question. I suddenly feel very humble because that is a question that I should have asked myself but I never have. Thank you. I asked my friends to help me and here are the responses.

I have, discovered that electrons are still fundamental particles BUT they have found two types of electrons a negatively charged electron and a positively charged electron so they are now called leptons.  That does not however answer your question. What is a lepton made of?

My friends are quite correct Protons and Neutrons are no longer fundamental particles. (A fundamental particle is a particle that is not made of anything else) It was in 1911 that a scientist called Rutherford first discovered the proton and neutron. Then,in 1968, other scientists found that protons and neutrons were made up of fundamental particles called quarks. The next question of course is what are quarks made of?

To be continued

Hayley (11) asks “Were unicorns ever real????”

Thanks for the question Hayley. My friends are back from their holiday so I asked them ….this is their answer.

The fact that there are no fossils does not mean that unicorns never existed. If you look at how modern humans evolved (changed) from apes there are a lot of gaps in our understanding, which could be linked to fossils that have not yet been found.

Where fossils have been found we can get lots and lots of information from them especially from the age of the rock in which they are found. This is to do with something called radioactive decay. This allows the fossils to be placed fairly accurately on the ‘evolution table’.

Evolution is the change in the inherited characteristics of  populations of living things over successive generations. Evolutionary processes give rise to diversity at every level of the population. For example a pair of monkeys might give birth to an albino (white) baby. If that baby, when it is older, gives birth to an albino baby, we could call that an evolutionary change which might, in a few thousand years create a whole population of albino monkeys.

I have two immediate thoughts about unicorns. Firstly they are completely made up and secondly they are a brief part of an evolutionary  story that didn’t survive. For example an animal (horse, deer, goat or other animal) was born with one horn by some biological accident, it lived but it’s children were ‘normal’ so the trait ended.

I prefer the mythical, made up model. I would like your thoughts.

 

Is slime a solid or a liquid? asks Taya (11)

In development.

Hello Taya, many thanks for your question.  Slime is a fascinating substance and the best way of producing it is to mix a substance called Borax, with a substance like PVA with some water. There are other ways to do it but this is the traditional way. Is slime a liquid or solid?  How do we measure how ‘liquid’ something is. We use a measure of the way a liquid pours, or if you drop something (a small metal ball) into it …how quickly it falls through it. This property of liquids is called it’s viscosity. Like most scales of measurement there are usually two extremes  and something in the middle can have a little bit of both of the properties of a solid and a liquid – the slimes.

The Viscosity Scale was established by Newton in (would you believe it 1770 -almost 250 years ago). Slimes are registered as a Non-Newtonian fluids .

Why Borax and PVA? PVA is a substance called a polymer. A polymer is a long molecular particle of repeating units. Polymers usually quite happily slide over each other (not very viscous). Add borax and it’s molecules attach themselves to the PVA polymers and stop the easy sliding. Thus a slime is produced.

Uncertain about things in this answer. Please ask more. You can also look at this previous answer to a similar question.

Jaydeep (7) asks “Why do sponges absorb more hot water than cold water?”

Jaydeep. An interesting question, which I need to think about. I suspect it might be a question of ‘testing’. How did you arrive at the question? Did it include elements of ‘fair testing’? I shall start by passing it over to my friends.

Thanks team. Yes, I agree, science knowledge is based upon fair testing. Jaydeep’s question suggest that he has evidence that sponges absorb more hot water than cold. It is and interesting thought BUT is it true? That’s what a scientist would ask.

What do I think? My initial thought is that as water gets hot it expands, so…., the sponge might absorb less water. From another viewpoint it might be argued that the hot water ‘warms up’ the sponge and causes the sponge to expand, thus absorbing more water. Another argument might be that because both the water and the sponge expand when they get hot …..things cancel out.

The important point is that if the original investigation was not fair all the arguments about Why are meaningless.

Jaydeep ….do a fair test`and then ask the question. Many thanks for an interesting input.