Heat, light and sound

What is heat? Heat makes an object hotter. It always travels from hot objects to cold objects. Sources of heat Sources of heat produce heat. There are artificial sources and natural sources. Some artificial sources are: Wood, coal and oil. [...]

Changes of temperature If we put a hot object in direct contact with a cold object, heat will travel from the hot object to the cold object. The temperature of the hot object goes down. We can say that the temperature decreases. [...]

Why can we see objects? We can see objects because of light. It can come from natural sources such as the Sun or stars. It can also come from artificial sources such as candles and light bulbs. [...]

Mirrors A mirror is a piece of flat glass. One side is covered with shiny metal, which reflects light. We see an image of the person or object in front of it. This is called reflection. [...]

What is sound? Sound is produced when an object vibrates. We hear sound using our sense of hearing. We can hear sound from different sources: The human voice produces sound when we talk because the vocal chords in the throat vibrate. [...]

Heat, light and sound are all around us. We can feel heat from the Sun in the summer and from a radiator in the winter. We need light to see people and objects. We get light from the Sun during the day and from lamps during the night. [...]

Do an experiment with heat What do we need? A metal knitting needle. A thick sewing needle. A toothpick. A cork. Three large books. A metal box. A candle. [...]

Heat, light and sound are all around us. We can feel heat from the Sun in the summer and from a radiator in the winter. We need light to see people and objects. We get light from the Sun during the day and from lamps during the night. [...]