1.Name five objects which can be made from wood.
1.Name five objects which can be made from wood.
Explanation:
Wood is a versatile material and can be used to make a wide range of objects. Here are five examples:
Furniture: Wood is commonly used to make chairs, tables, beds, and other pieces of furniture.
Musical Instruments: Many musical instruments, such as guitars, violins, and drums, are made from wood.
Utensils: Spoons, bowls, and cutting boards are commonly made from wood.
Tools: Handles for hammers, axes, and other tools are often made from wood.
Toys: Wooden toys are a popular choice, with examples including building blocks, puzzles, and dollhouses.
2.Select those objects from the following which shine: Glass bowl, plastic toy, steel spoon, cotton shirt.
2.Select those objects from the following which shine: Glass bowl, plastic toy, steel spoon, cotton shirt.
Explanation:
The objects that shine are the glass bowl and the steel spoon. Glass is known for its reflective properties and steel has a polished surface that can reflect light. The plastic toy and cotton shirt do not have a shiny appearance.
3. Match the objects given below with the materials from which they could be made. Remember, an object could be made from more than one material and a given material could be used for making many objects.
3. Match the objects given below with the materials from which they could be made. Remember, an object could be made from more than one material and a given material could be used for making many objects.
Explanation:
Book is made of Paper (because it is lightweight and easy to print on).
Tumbler is made of Glass or Plastic (because they are transparent and easy to shape).
Chair can be made using Wood Or Plastic (because they are sturdy and durable).
Toys are generally made of Plastic or Wood (because they are lightweight and easy to shape).
Shoes can be made using Leather (because it is flexible and comfortable).
4.State whether the statements given below are ‘true’ or ‘false’.
(i) Stone is transparent, while glass is opaque.
(ii) A notebook has lustre while eraser does not
(iii) Chalk dissolves in water.
(iv) A piece of wood floats on water.
(v) Sugar does not dissolve in water.
(vi) Oil mixes with water.
(vii) Sand settles down in water.
(viii) Vinegar dissolves in water.
4.State whether the statements given below are ‘true’ or ‘false’.
(i) Stone is transparent, while glass is opaque.
(ii) A notebook has lustre while eraser does not
(iii) Chalk dissolves in water.
(iv) A piece of wood floats on water.
(v) Sugar does not dissolve in water.
(vi) Oil mixes with water.
(vii) Sand settles down in water.
(viii) Vinegar dissolves in water.
Explanation:
(i) False - Stone is usually opaque, glass is transparent.
(ii) False - Notebook has no lustre, eraser can have.
(iii) False - Chalk doesn't dissolve, it's insoluble.
(iv) True - Wood is less dense than water.
(v) False - Sugar dissolves in water.
(vi) False - Oil and water are immiscible.
(vii) True - Sand is denser and settles.
(viii) True - Vinegar is soluble in water.
5. Given below are the names of some objects and materials: Water, basketball, orange, sugar, globe, apple and earthen pitcher.
Group them as:
(a) Round shaped and other shapes
(b) Eatables and non-eatables
5. Given below are the names of some objects and materials: Water, basketball, orange, sugar, globe, apple and earthen pitcher.
Group them as:
(a) Round shaped and other shapes
(b) Eatables and non-eatables
Explanation:
(a) Round shaped objects: basketball, orange, globe, apple.
Objects with other shapes: water, sugar, earthen pitcher.
(b) Eatables: orange, sugar, apple.
Non-eatables: water, basketball, globe, earthen pitcher.
6. List all the items known to you that float on water. Check and see if they will float on oil or kerosene.
6. List all the items known to you that float on water. Check and see if they will float on oil or kerosene.
Explanation:
Some items that float on water include wood, plastic, rubber, cork, and foam. When tested, these items will also float on oil or kerosene since they have a lower density than the liquids. Other liquids with higher densities like alcohol, gasoline, and many oils will cause these items to sink.
7.Find the odd one out from the following:
(a) Chair, Bed, Table, Baby, Cupboard
(b) Rose, Jasmine, Boat, Marigold, Lotus
(c) Aluminium, Iron, Copper, Silver, Sand
(d) Sugar, Salt, Sand, Copper sulphate
7.Find the odd one out from the following:
(a) Chair, Bed, Table, Baby, Cupboard
(b) Rose, Jasmine, Boat, Marigold, Lotus
(c) Aluminium, Iron, Copper, Silver, Sand
(d) Sugar, Salt, Sand, Copper sulphate
Explanation:
(a) Baby, because it is not a piece of furniture like the other items.
(b) Boat, because it is not a type of flower like the other items.
(c) Sand, because it is not a metal like the other items.
(d) Sand, because it is not a soluble substance, unlike the other items which dissolve in water.
8.Why do we need to group materials? Give one reason.
8.Why do we need to group materials? Give one reason.
Explanation:
We need to group materials to classify and organize them based on their common properties or characteristics. This helps us understand the properties and behavior of materials and how they can be used for different purposes. It also helps in identifying the appropriate materials for specific applications, such as selecting materials for construction or manufacturing.
9.Suggest two bases on which we can group objects.
9.Suggest two bases on which we can group objects.
Explanation:
Two bases on which we can group objects are:
Physical properties - This includes properties such as size, shape, color, texture, and density. Objects can be grouped based on these properties, such as grouping all red objects or all objects that are soft to the touch.
Material composition - Objects can be grouped based on the materials they are made of, such as grouping all objects made of wood or all objects made of plastic. This helps in understanding the properties and behavior of materials and how they can be used for different purposes.
10.Which material is generally used for making pens? Wood, aluminium, plastic, cotton.
10.Which material is generally used for making pens? Wood, aluminium, plastic, cotton.
Explanation:
Plastic is the material that is generally used for making pens. This is because plastic is durable, lightweight, and can be molded into different shapes and sizes easily. It is also relatively cheap to produce and can be mass-produced, making it a cost-effective option for pen manufacturing. Wood and aluminium are not commonly used for pen making, while cotton is not used at all.
11.Name two objects which are made from opaque materials.
11.Name two objects which are made from opaque materials.
Explanation:
Two objects which are made from opaque materials are a brick and a book. Bricks are made from materials like clay or concrete which are opaque, while books are typically made from paper or cardboard which is also opaque.
12.Which is harder, sponge or iron?
12.Which is harder, sponge or iron?
Explanation:
Iron is harder than sponge. Sponge is a soft and porous material that can be easily compressed or deformed, while iron is a dense and rigid metal that is much harder to compress or deform. Iron is used in a variety of applications that require a strong and durable material, while sponge is typically used for cleaning or padding purposes.
13.Why is a tumbler not made with a piece of cloth?
13.Why is a tumbler not made with a piece of cloth?
Explanation:
A tumbler is not made with a piece of cloth because cloth is not a suitable material for holding liquids. Cloth is porous and can easily absorb liquids, causing them to leak or spill. Additionally, cloth is not rigid enough to hold its shape and could collapse when filled with liquid. Instead, materials such as glass, plastic, or metal are used to make tumblers.
14.What are the similarities between iron, copper and aluminium?
14.What are the similarities between iron, copper and aluminium?
Explanation:
Iron, copper, and aluminium are all metals that are good conductors of electricity and heat. They are also ductile, meaning they can be easily drawn into wires, and malleable, meaning they can be easily shaped into different forms without breaking. Additionally, all three metals are commonly used in a variety of industrial applications due to their desirable properties.
15.Metals have lustre (shine). Give a reason why some metal articles become dull and lose their shine.
15.Metals have lustre (shine). Give a reason why some metal articles become dull and lose their shine.
Explanation:
Metal articles become dull and lose their shine due to the process of oxidation. When metals react with oxygen in the air or with other chemicals, a layer of metal oxide forms on the surface of the metal. This layer is often dull and can obscure the shine of the metal underneath. Additionally, scratches or other physical damage to the surface of the metal can also reduce its shine.
Also Read: Chapter 5: Separation of Substances
