S4 reaction times

When we started the transport unit a couple of weeks ago, we investigated the reaction times of different people in the class by getting them to time how long it took for Andrew’s plasticine to fall from the ceiling to the floor.

I found a great game on the BBC website that will allow you to measure (and perhaps improve) your own reaction time .  Why don’t you try it for yourself and post your best times in a comment.

S3 – movement from electricity

Last week we looked at using electricity to get things moving. We looked at examples of an electric bell and the movement of a current-carrying bar of copper in a magnetic field. We’ll be taking an electric motor apart this week to see how it works but in the meantime, here is a link to an animation of an electric buzzer (same idea as the electric bell).

If you want to read someone else’s explanation of how an electric motor works, you could go here or here. There are animations of a dc electric motor here and here (this is the example I used in class).

almost there!

We have almost completed the Using Electricity unit. We will start looking at magnetism tomorrow as an introduction to movement from electricity. The closer we get to the end of a unit, the nearer we are to test time.

You might want to download a copy of this electricity revision booklet to help you check how well you understand the topics we have covered. It also contains some useful revision questions in the homework section.

series or parallel?

We’ve been looking at the different properties of series and parallel circuits over the past week or so.  Since there are only 91 days left until Christmas, I thought I would ask you all for some shopping advice.

tree

I need a new set of Christmas tree lights.  Should I be in the market for a set of lights built in series or parallel?  Don’t forget to tell me what information influenced your choice!

If you’re not sure why the series/parallel decision would make a difference to tree lights, you might want to check this site.  There’s also some information on series and parallel circuits here.