8. MOTION
Q.1 Define uniform motion.
Ans. When a body covers equal distance in equal interval of time, it is called uniform motion.
Q.2 What is speed?
Ans. Speed is defined as the distance travelled per unit time by an object.
Q. 3 Define acceleration.
Ans. The rate of change of velocity of an object is called acceleration.
Q. 4 Give any one difference between distance and displacement.
Ans. Distance is the path followed by an object to reach the final position whereas displacement is the shortest path followed by the object to reach the final position.
Q.5 Give any one difference between speed and velocity.
Ans. Speed is a scalar quantity but velocity a is a vector quantity.
Q.6 What are scalar and vector quantity.
Ans. Scalar → The physical quantity which have only magnitude but no direction.
Vector →The physical quantity which have both magnitude and direction are vector quantity.
Q.7 What is the SI unit of acceleration?
Ans. The SI unit of acceleration is m/s 2.
Q.8 Define circular motion.
Ans. The motion of an object around a circular path is called circular motion.
Q. 9 What does the odometer of an automobile measure?
Ans. The odometer of an automobile measures the distance covered by it.
Q.10 What is the nature of distance- time graph for uniform and non-uniform motion?
Ans. For uniform motion the graph is a straight line and for non-uniform motin the graph is zig-zag.
15. IMPROVEMENT IN FOOD RESOURCES.
Q.1 What do you mean by Weeding?
Ans. The process of removing weeds from a crop field is called weeding.
Q. 2 What is mixed cropping?
Ans. The process of growing two or more crops on the same piece of land simultaneously is called mixed cropping.
Q. 3 Give one example of each of viral and bacterial disease of cattle.
Ans Viral disease→ foot and mouth disease.
Bacterial disease→ anthrax.
Q. 4 Stat any one factor which affects the quality of honey produced.
Ans. The quality of honey produced depends upon the flowers available to the bees for nectar or pollen collection.
Q. 5 Define crop rotation.
Ans. The growing of crops alternatively one after the other is called crop rotation.
Q. 6 What do you mean by vermicomposting?
Ans. The compost which is prepared by waste like vegetables waste, animal refuse, domestic waste etc. by use of earthworms is called vermicomposting.
Q. 7 What are biotic factors?
Ans. The natural and non- living factors which affects the agriculture and environment are called abiotic factors.
Q. 8 Name two Indian breeds of cow.
Ans. Sahiwal and Gir.
Q. 9 What is poultry?
Ans. Poultry is the branch of animal husbandry which deals with the rearing of birds for eggs and meat.
Q.10 Give two examples of shellfishes.
Ans. Crab and octopus.
6. TISSUE
Q.1 Define a tissue.
Ans. A group of similar cells that performs a specific function is called tissue.
Q. 2 How many types of plants tissues are there? Name them.
Ans. There are two types of plants tissues meristamatic and permanent tissues.
Q. 3 Name the different types of simple tissue.
Ans. Parenchyma , collenchyma and sclerenchyma.
Q. 4 What are the constituents of phloem?
Ans. The constituents of phloem are sieve tubes, companion cells, phloem fibres and phloem parenchyma.
Q. 5 What is the function of areolar tissue?
Ans. This tissue acts as a supportive and packing tissue between organs lying in the body cavity and also help in repairs of tissues.
Q. 6 Name the four elements of xylem.
Ans. Tracheids ,vessels, xylem parenchyma and xylem fibres.
Q.7 What is epithelial tissue?
Ans. The covering or protective tissue in animals body is called epithelial tissue.
Q.8 Write any one function of epidermis.
Ans. Epidermis protects the plant from excessive heat or coldand from the attack of parasites like fungus or bacteria.
Q. 9 Give any one role of cork in plants.
Ans. It provides protection from mechanical injury, temperature, fire and parasites etc.
Q.10 Define the process of differentiation.
Ans. The loss of ability of the cells to divide by taking up a permanent shape, size and function is called differentiation.
9. FORCE AND LAW OF MOTION
Q.1 What is meant by force?
Ans. The push or pull exerted on an object to bring a change in its state of rest or of motion is called force.
Q.2 State the name and type of force which is responsible for the formation of tides in sea.
Ans. Gravitational pull of moon.
Q.3 What is inertia?
Ans. It is the property of a body by virtue of which it resists any change in its state of rest or of motion is called inertia.
Q. 4 Name the physical quantity on which the inertia of a body depends.
Ans. Mass of the body.
Q. 5 Define momentum. State it SI unit also.
Ans. The momentum is define as the product of mass and velocity of a object. Its SI unit is Kg m/s.
Q. 6 State Newton’s second law of motion.
Ans. It states that the force exerted upon an object is directly proportional to the rate of change of its momentum.
Q.7 State newton’s third law of motion.
Ans. Newton’s third law states that for every action there is equal and opposite reaction.
Q.8 A balloon is inflated and released. Why does it fly forward as air escape out of it?
Ans. Air pushed out of the balloon exerts an equal reaction force on the balloon and it moves forward.
Q. 9 Why is a groove provided in a saucer for placing tea cups?
Ans. The groove prevent the cups from toppling over in case of sudden jerks.
Q.10 Define impulse.
Ans. It is define as the product of force and time i.e. impulse= force x time.
4. STRUCTURE OF ATOM
Q.1 Who discovered the electron?
Ans. J.J. Thomson discovered the electron.
Q.2 What is a proton and who discovered it?
Ans. Proton is a positively charged particle present in the nucleus. It was discovered by Goldstein.
Q.3 Define valancy.
Ans. Valancy is the no. of electron gained or lost or shared by an atom.
Q.4 What are isotopes?
Ans. Atoms of the same element having same atomic no. but different atomic mass are called isotopes.
Q.5 What is the valancy of silicon and oxygen?
Ans. The valancy of silicon is four and that of oxygen is 2.
Q.6 Define isobars.
Ans. Atoms of the different elements having different atomic no. but same atomic mass are called isobars.
Q.7 Why did Rutherford select a gold foil in his x-ray scattering experiment?
Ans. It is because gold is highly malleable and thus a very thin fold can be obtained.
Q.8 An element X has mass number 4 and atomic number 2. Write the valancy of this element.
Ans. Its atomic number is 2, it has 2 electron in 1st shell. Its valancy is zero as it has stable electronic configuration.
Q. 9 Who discovered neutron?
Ans. Chadwick.
Q. 10 Write any one use of isotopes.
Ans. C-14 is used to determine the age of the fossil of the living organisms.
3. ATOM AND MOLECULES
Q.1 Define atomicity.
Ans. Atomicity is define as the no. of atoms present in a molecule.
Q.2 What is the formula of ammonium chloride?
Ans. NH4Cl.
Q.3 Define atomic mass unit.
Ans. Atomic mass unit is define as the 1/12th of the mass of 1 atom of C-12. It is called unified mass also.
Q.4 What is meant by Avogadro’s constant?
Ans. Avogadro’s constant is equal to 6.022x1023.
Q.5 What is a molecule?
Ans. The molecule is made up of atoms which has free existence in nature.
Q.6 What is meant by the term chemical formula?
Ans. A chemical formula of a compound is the symbolic representation of its constituent elements.
Q.7 Give the name of the elements present in the following compounds- baking powder, potassium sulphate .
Ans. Baking powder→ sodium, hydrogen, carbon and oxygen.
Potassium sulphate→ potassium, sulphur and oxygen.
Q.8 What is the chemical formula of quick lime?
Ans. CaO.
Q.9 Name the cation and anion which constitutes the molecule of magnesium oxide.
Ans. Mg+2 is cation and O2- is anion.
Q.10 Does the solubility of a substance change with temperature/
Ans. Yes, the solubility of a substance increase with increase in temperature.
7.DIVERSITY IN LIVING ORGANISMS
Q.1 What do you mean by the term biodiversity?
Ans. Millions of different life forms found on earth surface constitutes the biodiversity.
Q.2 Write different steps of hierarchy of classification.
Ans. Kingdom, phylum, class, order, family, genus and species.
Q.3 Who proposed five system of classification?
Ans. Robert Whittaker.
Q.3 Name the five sub- groups of vertebrates.
Ans. Pisces, amphibian, reptilian, aves, mammalia.
Q.4 Write any one difference between angiosperm and gymnosperms.
Ans. Angiosperms have enclosed seeds whereas gymnosperms have their nacked seeds.
Q.5 What is the role of International Code of Binomial Nomenclature?
Ans. It sets rules and guidelines for the binomial nomenclature.
Q.6 What is a notochord?
Ans. A notochord is a primitive back bone which is rigid, cartilaginous rod present in some stages of development in all organisms.
Q.7 On what basis all the organisms or animals divided?
Ans. Animals are classified on the basis of-
· Body organisation.
· Symmetry.
· Presence or absence of notochord and body cavity.
Q.8 What is the most important feature of arthropoda?
Ans. They possess joint legs.
Q.9 Give one difference between cartilaginous and bony fishes.
Ans. Cartilaginous fishes have ventral mouth and uncovered gills whereas bony fishes have terminal mouth and operculated gills.
Q.10 How are oviparous and viviparous animals differ from each other?
Ans. Oviparous animals lay eggs like birds whereas viviparous animals give birth to young ones like mammals.
10. GRAVITATION
Q.1 Define the term Gravitation.
Ans. The attractive force between any two objects of the universe placed at a certain distance apart is called gravitation.
Q.2 What is free fall?
Ans. When an object falls towards another object under the effect of gravity, then it is called free fall.
Q.3 What is the difference between gravity and gravitation?
Ans. Gravitational pull of earth is called gravity while gravitation is the attractive forces between any two objects in the universe.
Q.4 What is the significance of law of gravitation?
Ans. Planetary motion around the sun, occurrence of tides etc.
Q.5 What is acceleration due to gravity?
Ans. The acceleration experienced by an object during the course of its free fall is called acceleration due to gravity.
Q.6 How does the value of g vary with the mass of an object?
Ans. The value of g is independent of the mass of an object.
Q.7 State the SI units of G and g.
Ans. The unit of G is Nm2kg-2 and unit of g is ms-2.
Q.8 Why does the weight of a body differ from poles to equator?
Ans. Weight of an object decrease from poles to equator.
Q.9 Give the characteristics of gravitational force.
Ans. It is a weak force, always attractive in nature and long range force.
Q.10 What is the value of G?
Ans. Its value is 6.673x10-11Nm2kg-2.
11.WORK AND ENERGY
Q.1 Define work.
Ans. Work is said to be done when an applied force produces a displacement in the body in its own direction.
Q.2 What is power?
Ans. The rate of doing work is called power.
Q.3 What is kinetic energy of an object?
Ans. The energy possessed by an object by virtue of its motion is called its kinetic energy.
Q.3 Define 1 joule of work.
Ans. Work done is equal to 1 joule when a force of 1 N displaces a body by 1m in its own direction.
Q.4 State any one condition of zero work done.
Ans. When no displacement occur I force is applied , the wok done is said to be zero.
Q.5 Define potential energy.
Ans. The energy possessed by an object by virtue of is position is called its potential energy.
Q.6 Give one example of negative work.
Ans. When a load is lifted, the work done is negative.
Q.7 State the law of conservation of energy.
Ans. It states that energy can neither be created nor be destroyed ,it can only be converted from one form to another.
Q. 8 What is the commercial unit of energy?
Ans. The commercial unit of energy is kilo watt hours.
Q.9 Define 1 watt.
Ans. Power is equal to 1 watt If any device does 1J of work in one second..
Q.10 Do work and energy have same unit?
Ans. Yes, both energy and work done have same unit.
13.WHY DO WE FALL ILL
Q.1 What is immunisation?
Ans. The introduction of any kind of germs or microbes into the body of an living being by vaccination to activate the immune system against a particular infection is called immunisation.
Q.2 Write any two basic condition necessary for keeping good health.
Ans. Balanced diet and keeping personal and domestic hygiene.
Q.3 What is an antibiotic?
Ans. Antibiotic is a chemical substance produced by living organisms and used to kill or stop the growth of micro organisms are called antibiotic.
Q.4 Name any one disease which is spread by water.