# “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

# Imran (age 10) asked “If I was to push a ball , how does it stay moving even after I pushed it?”

Imran. A great question. I would like to answer it in a slightly different way (you can sometimes do that with questions). After you push a ball it starts moving but does it stay moving?

When you push the ball you transferring your push (force)  to the ball and it moves. Newton (a great scientist and questioner) thought “Why does it stop moving? I have transferred my force to the ball and it should keep moving until it transfers that force to something else” But it does stops moving. I put this question to my friends and they came up with the following thoughts.

Why not investigate moving balls over different surfaces. You could use wood, paper, carpet, or the floor as surfaces and see how far the ball rolls BUT you have to make it a fair test. How do you create the same force?  How do you transfer the same force to the ball?

What would be your prediction (educated guess) about what the result would be? All scientist’s make predictions and then they test them.  My last question is, if there is something stopping the ball from rolling …. what do you think it is? has it got a name? If you have an answer you can leave it in the  ‘Leave a Reply’ box below. Want to ask another question …go to

# Maryam (age 10) asked a question on forces. “What do forces have to do with science?”

Maryam

What an excellent question. How do I answer this? Firstly I think we need to know what we mean by science. Here is what my friends said when I asked them the question.

My favourite definition of science is that it is ‘applied curiosity’. People who enjoy science have a curiosity about the physical and natural world that surrounds them. This leads them to investigate it.

Look at the see-saw in the picture above. Why does a small mass seem to balance a larger mass? Lets move the masses around and see if we can get other positions where they balance? This is curiosity in action.

So what about forces, are they part of the natural world or the physical world? What is a force?

The forces we meet every day are pushes and pulls. Pushes and pulls make things move.

Gravity is another force … jump off a chair and you are pulled to the ground, you moved because of the pull of gravity. Another force is friction – how does that affect movement? Force and movement are therefore intertwined. Investigate movement and you are investigating forces. And that leads to lots of questions. Do things always move at the same speed when a force is applied? Curiosity, curiosity, curiosity.

So please show your curiosity by asking more questions and I leave you with a question of your own. Are forces part of the natural world or the physical one, or both, or neither?

I hope this gives you some answers to your excellent question. Any more questions?