Author: roger

primary: which colour for cycling

Most substances reflect some light and that is why we can see them. White light is a mixture of many colours mixed together. When white light shines on say, a blue fabric, the fabric reflects blue and absorbs every colour except blue. Similarly a red fabric reflects red and absorbs all other colours. A black fabric …

primary: which light is brightest?

We need light to see things and light comes from something that is hot or burning. A torch or light bulb has tungsten wire which glows when hot. Candles produce light by burning chemicals. Some light ..

primary: make ear muffs for teacher

Noise is sound being a nuisance or causing ear damage but sound proofing against this is difficult. This is because all sorts of materials vibrate and transmit sound. Having sound absorbers, such as carpets and curtains helps to absorb sound. Also ..

primary: make your hot drink cool

Hot things cool because they lose heat to their surroundings. We can help them to cool by making the surroundings cooler (by blowing) or by conducting heat away with a spoon. The greater the difference..

primary: keep baby warm

Babies and adults are warmer than their surroundings and constantly lose heat to it. Other things being equal, how quickly they lose heat depends on their size and the surrounding temperature. The

primary: taking temperatures

If a cup of hot water has a higher temperature than the room, it loses heat energy to the room. In contrast, ice water, which has a lower temperature than the room, will gain heat energy from the room. Knowing the temperature of

weather station

Weather station With a data logger several sensors can be used together to monitor the weather over periods lasting weeks. Suitable sensors include temperature, pressure, humidity, light or even a rotation sensor to check...

burning a candle

Burning a candle As a candle burns oxygen is used and heat and water are produced. A few sensors can be used to monitor this process – including a light sensor to indicate when...

thermometric titration

Thermometric titration As acid reacts with alkali the pH changes and heat is evolved. This heat of neutralisation can be easily monitored using sensors – to produce a graph of temperature and pH against...

acid-base titration

Acid-base titration As acid drains into alkali the pH changes. This can be monitored using a pH sensor and instantly produce a graph of pH against volume. The volume of acid added is entered...

reaction rate: marble & acid

Rates: marble and acid Apparatus Clamps, bosses, & stands, marble pieces (large, medium and small sizes), 1M hydrochloric acid HCl, flask, bung, delivery tube, a good gas syringe. Interface, position sensor. Setting up Set...