The faculty of science of the University of Hong Kong held The SMArt Weekend earlier this month, inviting students from secondary schools to science projects including making a pinhole camera on their own. This is Jeanie's report.
Knowledge comes first
On the first day, the programme started with a lecture about ceramics, followed by one about ferrofluid, which is a liquid that becomes a magnet, and surfaces that are superhydrophobic - meaning they cannot mix with water.
After that, there was a break where we got refreshments. I spoke to a few of my peers, and they were as happy to be there as I was. A lecture about sugar and another about pinhole cameras followed. Although students had to sit for four lectures in a row, they didn't seem bored - they even helped Professor Aleksandra Djurisiae, from the physics department, make butterflies out of sugar and sugar bubbles.
"I love cake making and am fascinated by kitchen science. The reason I teach students about sugar, despite having my hands burnt all the time, is that I want them to know about the physics and chemistry behind it," Djurisiae said.
No sitting on the armchair!
Four workshops were next - "Making Artistic Ceramics for Fun and Practical Use"; "Liquid Magnet and Water-Hating Super Coatings"; "The Sweet Adventure: Creating Your Own Sugar Art"; and "PinHoleCam-ology". In the ceramics workshop, participants worked with the creative team members to build an object with every shape we could imagine.
In the next workshop, we made our own liquid magnet and water-hating super coating as well as learning the science behind the amazing properties.
The sugar workshop was perfect for sweets lovers. We enjoyed turning sugar into other tasty forms, such as cotton candy, marshmallows and honeycombs.
I thought the pinhole camera-making workshop was the most fascinating, as we made our own camera and learned the theories behind it. We took a metal box, and stuck black tape to the inside to cover up the reflective surface. This makes sure that no unwanted light reaches the film. We drilled a hole in the box, and cut a small strip of very thin aluminium. We made a pinhole in the aluminium and taped it over the hole in the box. The purpose of this is to let light stream in through the small entrance and form a picture on the light-sensitive material, in this case, photo film.
When we were all ready, we switched off the lights in the room and replaced them with red ones to prevent the film being exposed to white light, which would ruin the final picture. We loaded the photo film into our cameras, then covered up the hole with black tape before running around the campus to find good picture spots. When we did, we just peeled off the tape to take a picture. The last step was to put the film into two liquids, the developer and fixer, to develop the picture. Even though most of the pictures somehow went wrong, we were still so delighted we could make our own pinhole camera.
7-metre balloon pyramid!
On the second day, we built a large balloon pyramid. Participants built a fractal in the shape of a Sierpinski tetrahedron, which is a pyramid with four triangular faces and a square as a base. A "fractal" is a naturally occurring pattern that repeats itself. It is also common in art. It helped me to understand complex, dynamic systems.
With the HKU student helpers, I used two balloons to make a small pyramid, classified as level one.
When we tied four of them together, a level-two fractal was formed. The aim was to build a balloon pyramid with six levels, which was more than seven metres tall, and we made it!
Balloons burst and fingers ached from tying them, but we had a great time.