# Lesson video

In progress...

Hi everybody.

Today, we are going to be interrupting time graphs.

So, before we begin put on your hat , tighten those ties and tell the computer, now I'm a mathematician.

Super.

Let's get started.

For today's lesson you are going to need the following resources.

You are going to need a pencil, a piece of paper and a ruler.

If you need to get any of those things, please do so now.

Super, let's get started.

Here is our lesson agenda.

First off, we're going to do our Star Words before looking at Leo's times.

It's then going to be question time before your end of lesson task.

So here are our ♪ Star words ♪ Come on, let's do it together ♪ Star words ♪ Super.

So we're going to look at our time graphs again and we're going to be comparing, reading scales, looking at data, using our axis with our horizontal, turning into dance moves and our vertical.

Super, let's get started.

[Announcer] So, Leo is cycling 20 km's and wants to record his speed.

He records the distance he has travelled in total, every five minutes to the nearest 500 metres.

Why would Leo want to record how far he has cycled every five minutes? Well, this is a really good way at seeing a breakdown of how fast he is going, for example, in the first five minutes, is he cycling further than the second five minutes? So, the first five minutes he might of only cycled 200 metres and then in the next five minutes, he might of cycled 400 metres.

The best way for athletes to maintain their speed is if they try and cycle the same amount every five minutes, which means, he won't get tired because he's not going too far, too fast in one set of five minutes or too slow in one set of five minutes.

So here is his times that he's recorded, so along the top we have the times, starting at 13:00 pm or one o'clock in the afternoon and it finishes at 13:55 pm or one fifty five in the afternoon and you can see that he started off cycling 0 km's.

In the first five minutes he cycled two km's 500 metres.

In the second five minutes he cycled 6 km's, in total, then he cycled 9 km's.

Then he got to 10.

5 km's then 11 km's, so he slowed down there.

Then 11.

5 km's, then he cycled up to 14.

5 km's, then, oh, between 13:40 pm and 13:45 pm he saved 17 km's, so he may of had a little five minute break there and then he started off again because at 13:50 pm you can see, he cycled up to 18 km's and then at 13:55 pm he finished and he had cycled 20 km's, that's really far.

He then plotted his results on a time graph.

So here are some questions, let's have a look at them together.

Did Leo cycle quicker at the beginning or the end of the ride? How do you know? So, I can see here at the beginning of his ride, that is quite a steep curve going upwards, which shows me that he was cycling quicker.

When might he have been cycling uphill? How do you know? Now here, we can see, it's not as steep is it? So, from around here, so, from 13:20 pm to 13:25 pm, just before 13:30 pm he would have been cycling uphill because you can see that the curve is starting to slow down a bit.

When might he have been cycling downhill? How do you know? Well, we're again looking for that steep curve because going downhill is much easier than going uphill, isn't it and you can move a lot quicker.

So, from here we can see in five minutes, he's done just under four km's and again, just under three km's here, so, at this area he would have cycled downhill because he's cycling very, very fast to have covered seven km's.

What may have happened between twenty to two and quarter to two? So, we need to make sure that we go to twenty to two and quarter to two and this is when the readings were both at 17 km's, so, I believe, that he might have had a little break there from all that cycling up and down hills.

For your independent task, you're going to write a diary account of what's happened during each part of Leo's cycle ride.

For example, Time: 13:00 pm to 13:05 pm, this is when he just started.

The cycle started so well, I had lots of energy so I was able to cycle quickly and I knew that a downhill was coming up.

So you need to write a little sentence for every time, for 13:00 pm to 13:10 pm.

From 13:10 pm to 13:20 pm and so on until 14:00 pm.

I'm really looking forward to reading these, so make sure you're using your best spelling, your best punctuation and any of your writer's toolkit techniques that you have learnt.

Don't forget to pause the video.