Tagged: primary

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