Birth to 10 Years in 1 Minute 25 Sec

Imagine your parents took a photo of you everyday of your life from birth to 10 years old and then compiled the photos into one large digital flip book? It might look pretty cool.

Well, J A Magic Films did just that, or near enough that, with little Natalie, and A LOT of people have viewed it. In fact, J A Magic Films’ time lapsed video has gone viral and, as of 30 Dec 2010, it has been viewed on YouTube nearly 4.5 million times.

What questions come to mind when you watch this clip?

Here are some of mine:

  1. Over 4.5 million YouTube views; how big is that number? What might I liken it to?
  2. If I was J A Magic Films and I received 1 cent for each YouTube view, would I be financially content? Might the sum pay for Natalie’s university education?
  3. The term “Time Lapse” is part of the title of this clip. I can visualise “time lapse”, but can I describe it in words?
  4. Did J A Magic Films really take a photo of Natalie every day for 10 years? In my correspondence with J A Magic Films, he explained that as Natalie got older it was more and more difficult to get a photo of her each day. He comments on his YouTube channel that 1,254 photos were taken in total.
  5. 1,254 photos taken over 10 years. That would mean Natalie had her photo taken – on average – every how many days?  Hmm… would I be that patient of a subject?
  6. 1,254 photos displayed in 1 minute 25 seconds. On average, how many seconds is each photo displayed?
  7. 1,254 photos. Might the original 1,254 photos fit on a memory stick? To estimate this, what type of assumptions will I have to make?

Have I missed any questions? If so, post your question(s) as a comment below. All contributers welcome!

A big thank you to J A Magic Films at YouTube for creating and sharing the video and Dan Meyer for inspiring me to do this type of lesson! Good man Dan!


Arc Length & Area of a Sector of a Circle

To determine arc length and the area of a sector of a circle, we make use of the circumference and circle area formulae.
By multiplying each formulae by the ratio of the given sector angle to a full 360 degrees, we arrive at the desired measurements.
In this video clip by, the instructor starts with reasoned semi-circle and quarter-circle examples and solutions. He then introduces the angle ratio to extrapolate a general formulae for finding all arc lengths and area.

In this clip from, the instructor uses common sense semi-circle and quarter-circle examples to introduce the general formulae for finding arc length and the area of a sector of a circle.