Tuesday, May 15, 2012
unit 18:air and water
air
Living things need a constant supply of oxygen and carbon dioxide in the air to survive.They also constantly give out carbon dioxide.Oxygen in the air never runs out,and the air is never completely filled with carbon dioxide clue to the oxygen and carbon dioxide cycle.
water
Water never runs out on the earth due to the water cycle.The water cycle is the continuous movement of water from the earth,to the sky and back to the earth.Movement of water in the water cycle requires neat from the sun to take place.
unit 21:Light and Heat
Light
light travels in a straight line and prom one medium to another and causing refraction.
refraction:
-when light passes through.
-a prism.
-droplets of rain.
-waterfall.
-spray of water from a garden hose
(all of these causing dispersion of the component colours of light.)
Colour of Light:
-Red
-Orange
-Yellow
-Green
-Blue
-Indigo
-Violet
Heat
Travels through conduction,convection and radiation.
unit 24:SOIL
Soil is a mixtureof decayed plants and animals,and small pieces of broken rocks,such as sand,silt and clay.The rocks are broken as a result of a process called Weathering.
Weathering is brought about by various agents in our environment,such as:
-Wind
-Waves
-Plants and Animals
-Frozen Water
-Water
-Heat from the Sun
-Human Activities
~SOIL EROSION~
The removal of soil by wind and rain is called soil erosion.Soil erosion occurs when soil gets blown by the wind or washed away by water.
The occurrence of the soil erosion depends on farious factors such as:
-Speed and Volume of running water.
-Amount of vegatation.
-Slope of land.
-Dryness and size of soil particles.
unit 23:Sound
Sound also travels in a similar way.When an object produce a sound, the sound travels away from the object
in all directions.The object producing the sound is called the source of the sound.
The loudness of a sound decreases as the sound travels farther away from the source.So, when we are very close to the source of a sound, it is very loud.As we move away from the source, the sound becomes softer.
Sounds requires a medium to travel.When an alarm clock rings, we can hear the sound because the sounds travels through the air and reaches our ears.In this case air is the medium through which sound travels.A space that has no matter in it is called a vacuum,A vacuum can be created in an empty jar by sucking out all the air from it.We cannot hear an alarm clock when it rings inside a jar with a vacuum,because there is no air or any other medium through which the sound can travel.Sound can travel through solid,liquid,and gas
Sound also travels in a similar way.When an object produce a sound, the sound travels away from the object
in all directions.The object producing the sound is called the source of the sound.
The loudness of a sound decreases as the sound travels farther away from the source.So, when we are very close to the source of a sound, it is very loud.As we move away from the source, the sound becomes softer.
Sounds requires a medium to travel.When an alarm clock rings, we can hear the sound because the sounds travels through the air and reaches our ears.In this case air is the medium through which sound travels.A space that has no matter in it is called a vacuum,A vacuum can be created in an empty jar by sucking out all the air from it.We cannot hear an alarm clock when it rings inside a jar with a vacuum,because there is no air or any other medium through which the sound can travel.Sound can travel through solid,liquid,and gas
REFLACTION
Making an electric circuit is fun but maybe it's a little bit hard.But if we do it really serious and concentrate
we can do it a little by a little.We can make a simple electric circuit.The materials are:
-Batteries
-Alligator clips
-Wires
-Bulbs
-Switch
We must very carefull when we want to cut the wires because when we want to cut the wires,the wire
will easily can be cut.
we can do it a little by a little.We can make a simple electric circuit.The materials are:
-Batteries
-Alligator clips
-Wires
-Bulbs
-Switch
We must very carefull when we want to cut the wires because when we want to cut the wires,the wire
will easily can be cut.
unit 19:gravitational and frictional force
Gravitational force
Gravitational force is a forcethat can act at a distance from an object.Gravitational force is the force of attraction between things and the earth.
Effects:gravitational force is acting on us and all other objects all the time.It is because of gravitational force that we are able to stand on the ground and not float away.Gravitational force also has many other effects.
Weight and Mass
simalirity:Both can be measured.
differences:-Weight:weight is a force.the gravitational force acting on an object.different at different places.the weight of an object is different on the earth,the moon and other planets.-Mass:mass is not a force.the amount of matter in an object.constant.the mass of an object is the same,regardless of where the object is.
Frictional force
Frictional force is a force that opposes motion.It is produced when two surfaces rub against each other.
Effects:-slow down and stop moving effect
-Prevent an object from starting to move.
-affect the movement of objects on different surfaces.
unit 20:ENERGY CONVERSION
Energy cannot be created or destroyed,but it can change from one form to another.
-Burning candle:chemical potential energy,light energy,heat energy.
-Battery operated toy car:chemical potential energy,electrical energy,kinetic energy.
-Paper aeroplane:chemical potential energy,kinetic energy.
-Recorder:chemical potential energy,kinetic energy,sound energy.
-Guitar:chemical potential energy,kinetic energy,sound energy.
-TV:electrical energy,light energy,sound energy,heat energy.
-Speakers:electrical energy,sound energy.
-Electric fan:electrical energy,kinetic energy,heat energy.
unit 21:Light and Heat
Light
light travels in a straight line and prom one medium to another and causing refraction.
refraction:
-when light passes through.
-a prism.
-droplets of rain.
-waterfall.
-spray of water from a garden hose
(all of these causing dispersion of the component colours of light.)
Colour of Light:
-Red
-Orange
-Yellow
-Green
-Blue
-Indigo
-Violet
Heat
Travels through conduction,convection and radiation.
unit 18:air and water
air
Living things need a constant supply of oxygen and carbon dioxide in the air to survive.They also constantly give out carbon dioxide.Oxygen in the air never runs out,and the air is never completely filled with carbon dioxide clue to the oxygen and carbon dioxide cycle.
water
Water never runs out on the earth due to the water cycle.The water cycle is the continuous movement of water from the earth,to the sky and back to the earth.Movement of water in the water cycle requires neat from the sun to take place.
unit 22:ELECTRIC CIRCUIT
An electrical appliance is made up of different components.These components are connected to form an Electric Circuit.
A simple electric circuit is made up of four components.These are the:
-energy source
-wires
-output device
-switch
~CIRCUIT DIAGRAMS~
component:
-Battery
-Wire
-Switch
-Bulb
unit 24:SOIL
Soil is a mixtureof decayed plants and animals,and small pieces of broken rocks,such as sand,silt and clay.The rocks are broken as a result of a process called Weathering.
Weathering is brought about by various agents in our environment,such as:
-Wind
-Waves
-Plants and Animals
-Frozen Water
-Water
-Heat from the Sun
-Human Activities
~SOIL EROSION~
The removal of soil by wind and rain is called soil erosion.Soil erosion occurs when soil gets blown by the wind or washed away by water.
The occurrence of the soil erosion depends on farious factors such as:
-Speed and Volume of running water.
-Amount of vegatation.
-Slope of land.
-Dryness and size of soil particles.
Subscribe to:
Posts (Atom)