What is "centripetal force"?

What is "centripetal force"?

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Centripetal force is an inward pull. It's almost like if you were thinking about a satellite orbiting the earth and the earth's gravity would create this inward pull. In fact, we could use a simple science toy to demonstrate this. If you take a balloon, this is a clear balloon (you can use any balloon to do this) and if you just go into mum or dad's little area where they keep old left over parts, just grab yourself a six sided nut and take the nut and drop it into the balloon. By the way, this is a very inexpensive toy. Once it's in there, you blow up the balloon. Now the balloon is going to represent the centripetal force on the nut and the nut is going to represent the satellite going around the earth. The earth would be positioned inside, right in the centre of the balloon. Now, once we get this nut moving it's going to make some noise. It's going around like this; it is moving around in a circle mainly because the gravitational pull of the earth keeps the satellite in that orbit and this balloon is representing this gravitational pull. Now, as this nut rolls around, you notice that it makes a little noise. If we roll this around again, it's making noise because we have a six sided nut; it's not very smooth, and every time it rolls over one of the bumps it makes a noise. It's almost like your car tire rolling over the bumps on the side of the road if you get off too far. OK, so it makes that same noise. Now, we can do the same thing and get a better look at the satellite end with a nickel and a balloon. So, we'll put the nickel in the balloon. This increases the value of the science toy by four cents I think. Now, we'll put this in here and then we'll blow this up and tie a knot in this balloon. Now, the nickel is going to represent the satellite going around the earth. The balloon is representing the gravitational pull keeping it in orbit, and as it's going around like this, you can see the satellite, our nickel, going around and the earth would be centred right in the middle of the balloon. The balloon is actually kind of representing the earth's gravitational pull, pulling it in. As soon as our gravitational pull balloon would break, the nickel would fly off into space.