Uses of Magnet

Magnet are of many use in our everyday life.What are some uses of magnets?

Refrigerator

- A magnet operates the motor .

- The door closes with the help of a magnet.

Pencil case

- A magnet pulls the lid of the pencil case shut.

Chess

-There is a button magnet on the base of every chessman so that they are stuck to the chessboard

Music box

- A magnet makes the figurine rotate when the box is opened.

Compass

-The needle is made from a magnet

-The needle always points to the direction of the magnetic north.

Bicycle

-The dynamo is operated bay a magnet.

-When the wheel turns,the magnet in the dynamo also turns and this in turn lights up the bulb.

The Light Rail Transit uses magnet to operate.

We will not be able to get electricity without magnets.Without magnets there will be no telephone, radio or television.

 

        refrigerator              compass                            chess

Magnets Attract Some Materials

Materials that are attracted by magnets
- needle
- iron ruler
- key

 paper clip 

                                                                                                         

  drawing pin                                                    safety pin

                                                                                                                

Materials that cannot be attracted to magnets

sliver ring                                                                

coin

• wood
• plastic bottle 
• paper
• marble
• pencil
• book
• handkerchief

Magnets attract things that are made of iron or steel.

Magnets do not attract things that are made of silver plastic or wood.

Magnets can Attract or Repel Each Other

Shape of magnets              
                                                                                     rod magnet

     

                                                       South pole                 North pole 

There are two types of magnets, natural magnets and man-made magnets.

Like poles of magnets repel each other

Unlike poles of magnets attract each other

when you break a bar magnet into two, you do not separate the North poles from the south poles. You will instead get two new magnets.

Magnets will lose their magnetism if:

1.dropped

2.heated

3.knocked

We should keep a magnet properly after use to avoid it losing its magnetism.

External Features of Plants

Surface, colours and shapes of leaves

1. sunflower leaf                  

   surface: smooth

   colour: green

   shape: heart-shaped

2. rose leaf

   surface: smooth

   colour: green

   shape: oval

3.bird's nest fern

   surface: smooth,shiny

   colour: green

   shape: long

4.coconut leaf

   surface: smooth

   colour: green

   shape: comb-like

5.papaya leaf

   surface: smooth

   colour: green

   shape: heart-palmate

Plant with woody stems and soft stems

    Flowering plants and non-flowering plants                                

• Most plants have green leaves.
• The shapes of leaves can be heart-shaped,oval,long,comb-like,palmate and round.
• Flowers function mainly as reproductive organs.

Grouping of Animals

1. Animals can be grouped according to their similar external features.

i. animals with fur

   - bear  - lion                                                 

ii. animals with scales

   -crocodile  -fish

iii. animals with horns

    -cow  -goat 

iv. animals with feathers

     -duck -eagle

v. animals with tail

-deer,tiger

vi. animals with wings

     -bee  -eagle                                                                                              

 A bird has wings and some insects also have wings.

2. Animals can be grouped according to their similarities.                                      

i. animals with                                                                                             

    -beak  -feathers  -wings  -claws  -two legs

     parrot , eagle                                                                                                   

ii. animals with 

    -tail   - scales                                                                                                  

     crocodile , fish

iii. animals with

    -fur  -four legs -tail

     bear , deer

Some animals have fur and some animals have scales on their bodies.       

3. Animals can be grouped according to their number of legs.                                

i. two legs

  -duck, eagle

ii. four legs

   -lion,cow,tiger

iii. six legs

    -mosquito,bee

Birds have two legs. Insects have six legs.

   

 

Similarities and Differences External Features

• Animals have similarities and differences in their external features.
• we can recognise an animal from its external features.

1. Animals which have similar external features.

               
 A mouse and  a cat have claws, fur, legs and tails.




     2.   Animals with different external features.

                                     

    A goat have hair                                A rhinoceros have skin

External Features of Animals

Each kind of animal has its own external features


                                                  External features of a crocodile

                                                  External features of a goat

                                     External features of a peacock