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.
(i) False
Stone is not an transparent object because it does not allow light to pass through it. While glass is transparent because it allows light to pass through it.
(ii) False
This statement is false because notebook and eraser both are not metals. So, they both do not contain luster.
(iii) False
Chalk does not dissolve in water because if this get dissolved in water it makes colloidal solution or we can say that it makes an heterogeneous mixture.
(iv) True
Wood floats on water because wood have less density than water.
(v) False
Because sugar dissolves in water and makes a saturated solution.
(vi) False
It is a false statement because oil has less density than water. So oil floats on water but do not mix with water. Oils are non- polar whereas water is polar. But both are immiscible liquids.
(vii) True
This statement is true because when sand mixes in water it makes colloidal solution and when this solution is left undisturbed it settles down in the bottom.
(viii) True
Because vinegar makes a homogeneous mixture or solution when mixes with water.
Draw (a) a leaf, (b) a taproot and (c) a flower, you have studied for Table 7.3.
You are given an iron strip. How will you make it into a magnet?
Name two foods each rich in:
(a) Fats
(b) Starch
(c) Dietary fibre
(d) Protein
A thick coating of a paste of Plaster of Paris (POP) is applied over the bandage on a fractured bone. It becomes hard on drying to keep the fractured bone immobilised. Can the change in POP be reversed?
Tick (√) the statements that are correct.
(a) By eating rice alone, we can fulfill nutritional requirement of our body. ( )
(b) Deficiency diseases can be prevented by eating a balanced diet. ( )
(c) Balanced diet for the body should contain a variety of food items. ( )
(d) Meat alone is sufficient to provide all nutrients to the body. ( )
List all items known to you that float on water. Check and see if they will float on an oil or kerosene.
Name the part of the plant which produces its food. Name this process.
Why can a pace or a footstep not be used as a standard unit of length?
Given below are the names of some objects and materials:
Water, basket ball, orange, sugar, globe, apple and earthen pitcher Group them as:
(a) Round shaped and other shapes
(b) Eatables and non eatables
Name two items that are made from coconut fibre.
How will you separate sand and water from their mixture?
Where are poles of a bar magnet located?
List all items known to you that float on water. Check and see if they will float on an oil or kerosene.
A magnet was brought from different directions towards a toy boat that has been floating in water in a tub. Affect observed in each case is stated in Column I. Possible reasons for the observed affects are mentioned in Column II. Match the statements given in Column I with those in Column II.
Column I Column II
Boat gets attracted towards the magnet Boat is fitted with a magnet with north pole towards its head
Boat is not affected by the magnet Boat is fitted with a magnet with south pole towards its head
Boat moves towards the magnet if north Boat has a small magnet fixed along its length
pole of the magnet is brought near its
head
Boat moves away from the magnet Boat is made of magnetic material when north pole is brought near its head
Boat floats without changing its direction Boat is made up non-magnetic material
Arrange the following lengths in their increasing magnitude:
1 metre, 1 centimetre, 1 kilometre,1 millimetre.
Tick (√) the statements that are correct.
(a) By eating rice alone, we can fulfill nutritional requirement of our body. ( )
(b) Deficiency diseases can be prevented by eating a balanced diet. ( )
(c) Balanced diet for the body should contain a variety of food items. ( )
(d) Meat alone is sufficient to provide all nutrients to the body. ( )
Name two foods each rich in:
(a) Fats
(b) Starch
(c) Dietary fibre
(d) Protein
In which part of a flower, you are likely to find the ovary?
How are clouds formed?
How are cactus adapted to survive in a desert?