a blog on stuff I find that makes me better at other stuff

Oblers’ Paradox and CMBR

September 17, 2015 • 

If you have a spare 20 minutes, this is an excellent explanation of Oblers’ paradox and the origin of Cosmic Microwave Background radiation as evidence to support the Big Bang Theory.

I hadn’t heard of the Hubble Sphere either…

September 17, 2015 •

So while this website is called “I CAN DO PHYSICS“, there is a lot of Physics I have never heard of before. I just stumbled upon this video from Veritasium which students might be interested to watch after studying Hubble’s Law.

It’s totally fascinating. I always thought the universe was finite, but maybe I’m wrong.

Either way, this Physics is so much fun.

Momentum problem in CfE Higher Physics

September 16, 2015 • 

Here is a short video solution to a typical momentum collision problem in Higher Physics. It describes two rugby players who collide and stick together. Using the principle of conservation of momentum, we can determine the velocity of the men after they collide.

The solution also determines if the collision is elastic or inelastic.

Rugby players collide

Tension problems in CfE Higher Physics

September 16, 2015 • 

Tension problems are a particular challenging subset of problem types in the Forces, Energy and Power section of the Our Dynamic Universe unit in Higher Physics. I’ve produced two videos explaining how to solve these types of questions, which are shown below.

The first one relates to three carriages on a track, and the second a more unusual (and rather funny) example of a cow dangling over a cliff! Both can be solved using two simple principles:

1. Find the unbalanced force on the whole system and then use it to determine the acceleration of the whole system.

2. Apply that acceleration to each component within the system to determine the tension providing the forward force for a component of the system.

Get all that…ok, maybe not. Hopefully the videos will make things a little more clear!

Train carriage problem

Cow over cliff problem

Mr Murray Physics

September 15, 2015 • 

When I set up this website, I had at the top of my mind what my USP is. That is, what can I offer on this site that no one else is doing. I’ve put many hours into producing past paper solutions, and I believe these are a highly valuable resource to Scottish students sitting SQA Physics exams.

Turns out, there are plenty of other teachers producing excellent content to support Physics students. I discovered the Mr Murray Physics Youtube channel recently and it’s great. I highly recommend a look.


On the topic of other sites for Physics students and teachers to use, is a great site produced by Nick Hood from Moray House, and contains a vast number of other useful links.

Most of my older classes seem to rave about It’s a great site for accessing past paper solutions and there is plenty of other resources that help students.

Let’s face it, the Physics teaching community in Scotland is vibrant.

Block quote test

Aug 19, 2015 • 

This is a test of the block quote look. It originally looked like this:

Screen Shot 2015-08-19 at 11.52.24

But after a few tweaks I hope you think it looks better (an smaller!)

The blockquote XHTML tag is a fairly useful (if somewhat underused) element. Semantically speaking, a blockquote should be used any time you’re quoting a longer piece of text from another source – another speaker, another website, whatever. It’s a way of setting the text apart, and showing that it came from some other source. Stylistically, you could accomplish all this with a special class on your paragraph tags… but that wouldn’t be as semantically useful, now, would it?

The learning process took 1/2 an hour of course!

Removing the title Category

Aug 18, 2015 • 

Another problem solved by googling.

The problem arose due to a bigger site design issue. I want to have an easy way to upload resources to the site without having to create loads of new pages, and I started to realise that using the blog to do this would be the most straightforward way. In that case, I simply create a post, categorize it as a resource for students or teachers, (potentially within a certain sub-category), and WordPress would automatically put the link in the right place, make it searchable and allow it to be easily found from the appropriate Category page, which would be linked to from the home screen.

The problem came when I made the Category pages. The title of each page was Category: Student Resources and Category: Teacher Resources. Having the word category didn’t look right.

Anyway, I found the solution in the link above. Essentially I pasted this text into the end of the functions.php file in the editor:

add_filter( 'get_the_archive_title', function ($title) {
 if ( is_category() ) {
 $title = single_cat_title( '', false );
 } elseif ( is_tag() ) {
 $title = single_tag_title( '', false );
 } elseif ( is_author() ) {
 $title = '<span class="vcard">' . get_the_author() . '</span>' ;
 return $title;

Now, I’ve no idea what all that means, but it works. I’d love to know how it works, but that’s for another day.

Bending light

August 18, 2015 • 

This is a great video from Physics World on how we can demonstrate bending light using very cheap high street lenses.

I’m definitely going to try this with my classes this coming session.


July 31, 2015 •

Amazing what you learn by googling. I was having trouble with some of the text hyphenating on small screens, I think due to the responsive design of the WordPress theme. Thankfully I found a solution. Simply adding

p {
 -moz-hyphens: none;
 -ms-hyphens: none;
 -webkit-hyphens: none;
 hyphens: none;

to the CSS style in the attribute options of the Page builder widget seems to solve the problem. On an aside, I also discovered how to add the lovely infinity symbol linking to the permalink for the blogpost, just add the html entity &infin; to the text. All works great.

Site development update

July 31, 2015 • 

So things are going well development wise, despite many late nights. My hope is to get the finishing touches done to the Exam support pages and then start uploading solution videos to Youtube to link to from this site. I’ve made a brief start on making videos, but it’s very time consuming.

My aim is to have the site ready for back to school mid August. No promises though! 😉