Text Book Solutions All Class

Q1: What is a partial solar eclipse?
Ans: A partial solar eclipse occurs when the Moon partially blocks the Sun.

Q2: Why is the Moon able to block the Sun during a solar eclipse?
Ans: The Moon is much smaller than the Sun, but it is much closer to the Earth, making it appear to cover the Sun.

Q3: What is rotation?
Ans: Rotation is the spinning of an object around its own axis.

Q4: What is the Earth’s axis of rotation?
Ans: It is an imaginary line that passes through the North and South poles.

Q5: How long does it take for the Earth to complete one rotation?
Ans: About 24 hours.

Q6: Which direction does the Earth rotate when viewed from the North Pole?
Ans: The Earth rotates in the anti-clockwise direction, from West to East.

Q7: What causes day and night on Earth?
Ans: The Earth’s rotation causes day and night.

Q8: What happens during the rotation of the Earth on its axis?
Ans: Half of the Earth faces the Sun and experiences daytime, while the other half experiences nighttime.

Q9: What direction does the Sun appear to move in the sky?
Ans: The Sun appears to rise in the East and set in the West.

Q10: What causes the stars to appear to move in the sky?
Ans: The Earth’s rotation causes the apparent movement of stars.

Q11: What is revolution?
Ans: Revolution is the movement of the Earth around the Sun along its orbit.

Q12: How long does the Earth take to complete one revolution around the Sun?
Ans: About 365 days and 6 hours.

Q13: Why do the stars in the night sky change over the course of a year?
Ans: The changing position of the Earth in its orbit around the Sun causes different stars to be visible at different times.

Q14: What causes the seasons on Earth?
Ans: The tilt of the Earth’s axis and its orbit around the Sun causes the seasons.

Q15: When does the Northern Hemisphere experience summer?
Ans: In June, when the Northern Hemisphere is tilted towards the Sun.

Q16: When does the Northern Hemisphere experience winter?
Ans: In December, when the Northern Hemisphere is tilted away from the Sun.

Q17: What is the
Ans: The longest day in the Northern Hemisphere, occurring around 21 June.

Q18: What happens during a solar eclipse?
Ans: The Moon blocks the Sun’s light from reaching the Earth.

Q19: What is a lunar eclipse?
Ans: A lunar eclipse occurs when the Earth blocks the Sun’s light from reaching the Moon.

Q20: Why should we not look directly at a solar eclipse?
Ans: Directly viewing a solar eclipse can damage the eyes and cause blindness.

Q1: Name an artificial source of light.
Ans: Electric bulbs.

Q2: What do fireflies use to communicate?
Ans: Fireflies use light to communicate.

Q3: What is a luminous object?
Ans: An object that emits its light.

Q4: Does the Moon produce its light?
Ans: No, the Moon reflects sunlight.

Q5: How does light travel under normal conditions?
Ans: Light travels in a straight line.

Q6: Name a natural source of light.
Ans: The Sun.

Q7: Give an example of a non-luminous object.
Ans: The Moon.

Q8:  Why are LED lamps promoted by the Indian government?
Ans: Because they are energy-efficient, brighter, and environmentally friendly.

Q9: What device uses two mirrors to see objects that are not directly visible?
Ans: A periscope.

Q10: What is the reflection of light?
Ans: When light bounces off a surface and changes direction.

Q11: What happens when light passes through aligned holes in a straight line?
Ans: It creates a bright spot on a screen.

Q12: What is a transparent material?
Ans: A material that lets light pass through almost completely, like glass.

Q13: What kind of material allows only some light to pass through?
Ans: Translucent material.

Q14: What is formed when an object blocks light?
Ans: A shadow.

Q15: What kind of shadow does an opaque object create?
Ans: A dark and well-defined shadow.

Q16: How does a pinhole camera form an image?
Ans: Light passes through a tiny hole and forms an upside-down image on a screen.

Q17: What type of image does a plane mirror form?
Ans: A virtual, upright, same-size, laterally inverted image.

Q18: What is lateral inversion in a mirror image?
Ans: The left side appears as the right side and vice versa.

Q19: What causes light pollution?
Ans: Excess artificial light from cities and towns.

Q20: What type of shadow do translucent objects create?
Ans: Lighter and less distinct shadows.

Q1: Name some components of food.
Ans: Carbohydrates, proteins, fats, vitamins, and minerals.

Q2: Define nutrients.
Ans: Carbohydrates, proteins, fats, vitamins, and minerals are essential components of food, these components are called nutrients.

Q3: Give an example of autotrophs.
Ans: All green plants.

Q4: Give an example of heterotrophs.
Ans: Animals and human beings.

Q5: Plants prepare their food by using raw materials present in their ______________.
Ans: Surrounding.

Q6: What do you mean by nutrition?
Ans: Nutrition is the mode of taking food by an organism and its utilization by the body.

Q7: Name the food factories of plants.
Ans: Leaves.

Q8: Name the tiny pores present on the surface of leaves.
Ans: Stomata.

Q9: Name the green pigment present in leaves.
Ans: Chlorophyll.

Q10: ____________ helps leaves to capture the energy of sunlight.
Ans: Chlorophyll.

Q11: Why is photosynthesis named so?
Ans: Because the synthesis of food occurs in the presence of sunlight.

Q12: Sun is the ultimate source of energy for all living organisms. True / False.
Ans: True.

Q13: State the equation for the process of photosynthesis.
Ans: Carbon dioxide + water → carbohydrate + Oxygen (in the presence of sunlight).

Q14: Why are algae present in stagnant water bodies green in color?
Ans: Because they contain the green pigment chlorophyll.

Q15: During photosynthesis, plants take in _______________ and release _______________.
Ans: Carbon dioxide and oxygen.

Q16: During photosynthesis solar energy is converted into chemical energy. True / False.
Ans: True.

Q17: The product of photosynthesis is
a. Carbohydrate
b. Protein
c. Fats
d. All of these
Ans: a. Carbohydrate.

Q18: Name a plant that has both autotrophic and heterotrophic modes of nutrition.
Ans: Insectivorous plants.

Q19: Name the pores present in leaves through which exchange of gases takes place.
Ans: Stomata.

Q20:What do plants need to grow?

Ans: Plants need sunlight, water, air, and nutrients to grow.

Q21. How do plants make their own food?

Ans: Plants make food through photosynthesis.

Q22. What is the role of sunlight in plant growth?

Ans: Sunlight provides energy for food production.

Q23. What do roots absorb from the soil?
Ans: Roots absorb water and minerals.

Q24.  What gas do plants take from air during photosynthesis?
Ans:  Plants take in carbon dioxide.

Q25. Where does photosynthesis mainly take place?
Ans: Photosynthesis mainly takes place in leaves.

Q1: Name the largest gland in the human body.
Ans: Liver

Q2: Animal nutrition includes
a. Nutrient requirements
b. Mode of intake of food
c. Utilization of food in the body
d. All of the above.
Ans: All of the above

Q3: Define digestion.
Ans: The process of breaking down complex substances of food into simpler forms is called digestion.

Q4: Name the parts of the alimentary canal.
Ans: Buccal cavity, oesophagus, stomach, small intestine, large intestine, rectum, and anus.

Q5: Name the glands that secrete digestive juice__________________.
Ans: Salivary gland, pancreas, and liver

Q6: The process of taking food into the body is called __________.
Ans: Ingestion

Q7: Name the different types of teeth.
Ans: Incisor, canine, premolar, and molar

Q8: The saliva breaks down starch into sugars. True/ False.
Ans: True

Q9: Name the mode of feeding of ants and mosquitoes.
Ans: The feeding mode of ants is Chewing (they use mandibles to bite and chew), and the mode of feeding of mosquitoes is sucking.

Q10: The tongue helps in mixing food with saliva. True/ False.
Ans: True.

Q11: Name ruminants.
Ans: Grazing animals like cows, buffaloes, and deer.

Q12: Name the finger-like projection present in the inner wall of the small intestine.
Ans: Villi

Q13: Name the organ responsible for removing undigested and unabsorbed residues from the human body.
Ans: Anus

Q14: Bile juice is stored in a sac called__________________
Ans: Gall bladder

Q15: Bile is responsible for the digestion of
a. Fat
b. Protein
c. Vitamins
d. Both a and b
e. None of these
Ans: Fat

Q16: What is the location of the pancreas?
Ans: The Pancreas is located just below the stomach.

Q17: The pancreatic juice acts on
a. Carbohydrates
b. Fats
c. Proteins
d. All of the above
Ans: All of the above.

Q18: Name the end products of carbohydrates.
Ans: Simple sugars such as glucose

Q19: Define egestion.
Ans: The process of removal of faecal matter from the body through the anus is called egestion.

Q20: How is food pushed down from mouth to stomach?
Ans: Food is pushed down by the movement of the wall of the food pipe.

Q21: The digestion of cellulose takes place in ________________ present in all ruminants.
Ans: Rumen

Q22: Name the part of the digestive canal involved in the absorption of food.
Ans: Small intestine

Q23: Name the part of the digestive canal that kills bacteria.
Ans: Stomach

Q24: Name the part of the digestive canal involved in the formation of faeces.
Ans: Large intestine

Q25: Name the part of the digestive canal involved in chewing food.
Ans: Mouth or Buccal cavity

Q1: The basic unit of speed is

(i) Km/ min

(ii) m/ min

(iii) Km/ sec

(iv) m/ sec

Ans : (iv) m/ sec

Speed is defined as the rate at which an object covers distance. It is measured in terms of how much distance is traveled per unit of time. In the metric system, the unit for distance is meters (m) and the unit for time is seconds (sec). Therefore, the basic unit of speed is meters per second (m/sec).

Q2: What is motion?

Ans : Motion is a change in the position of an object with time.

Q3: Define average speed.

Ans : The average speed of a moving object is defined as the total distance covered by it divided by the total time taken.

Q4: What do you mean by the statement; “car is moving with the speed of 50 Km per hour”?

Ans : Car is moving with the speed of 50 Km per hour it means it will cover a distance of 50 Km in one hour

Q5: What is a simple pendulum’s periodic motion?

Ans: A simple pendulum’s periodic motion involves oscillations back and forth from a center point.

Q6: What information can be interpreted from a distance-time graph?

Ans: A distance-time graph shows how distance changes over time and helps determine the speed of a moving object.

Q7: How do you define uniform motion?

Ans: Uniform motion occurs when an object moves along a straight line with a constant speed.

Q8: What is the time period of a simple pendulum?

Ans: The time period of a simple pendulum is the time taken for the pendulum to complete one full oscillation.

Q9:How is non-uniform motion different from uniform motion?

Ans: In non-uniform motion, the speed or direction of the object changes, whereas in uniform motion, the speed remains constant.

Q10: How do we measure speed using a speedometer and an odometer?

Ans: Speedometers measure and display the speed of a vehicle in km/h, while odometers record the distance traveled by the vehicle in kilometers (km).

Q11: The metallic ball in pendulum is called __________ of the pendulum. 

Ans: Bob

Q12: Give an example of oscillatory motion. 

Ans: To and fro motion of a simple pendulum

Q13: What is uniform motion?

Ans: Uniform motion is when an object covers equal distances in equal intervals of time.

Q14: Name the device used to measure speed. 

Ans: Speedometer

Q15: What is non-uniform motion?

Ans: Non-uniform motion is when an object covers unequal distances in equal intervals of time.

Q1: Define temperature.

Ans: The measure of hotness or coldness of an object is called temperature. It is usually measured in “degrees”.

Q2: Name the device used to measure temperature.

Ans: A thermometer is a device used to measure temperature.

Thermometer

Q3: What is the unit of temperature as adopted by India?

Ans: Degree Celsius (°C)

Q4: The bulb of the laboratory thermometer should not touch the surface of the ________________.

Ans: Container.

Q5: Give an example to show the transfer of heat from one body to another.

Ans: Any utensil kept on flame becomes hot because heat transfers from flame to the utensil.

Q6: Heat always flows from a hotter object to ________________.

Ans: Colder object

Q7: In solid heat is transferred by the process of

a. Conduction
b. Convection
c. Radiation
d. None of these

Ans: Conduction.

Q8: Give examples of conductors.

Ans: Aluminium, copper, iron, etc.

Q9: Give examples of insulators.

Ans: Wood, plastic, rubber

Q10: Insulators are ________ conductors of heat.

Ans: Poor

Q11: Conductors are _____________ conductors of heat.

Ans: Good

Q12: Name the process by which heat transfers in air.

Ans: Convection.

Q13: From the sun, the heat comes to us by the process called ________________.

Ans: Radiation.

Q14: Which of the two absorbs more radiation- a dark-coloured object or a light-coloured object?

Ans: A dark-coloured object.

Q15: Land breeze blows at the time of __________.

Ans: Night

Q16: Sea breeze blows at the time of _________.

Ans: Day

Q17: Which type of clothing should be preferred for the month of June?

Ans: Light-coloured clothes

Q18: Which type of clothing should be preferred in January?

Ans: Dark coloured clothes.

This should now be in the correct order without any missing questions! Let me know if you’d like further changes.

Q1: At what age does adolescence typically begin?
Ans: Around the age of 10.

Q2: What causes pimples to appear during adolescence?
Ans: Pimples appear due to an increase in oily secretions from the skin during adolescence.

Q3: What are secondary sexual characteristics?
Ans: Secondary sexual characteristics are signs that the body is preparing for adulthood, like voice changes and body hair growth.

Q4: What marks the onset of adolescence?
Ans: The onset of adolescence is marked by rapid growth and development.

Q5: What happens to boys’ voices during adolescence?
Ans: Boys’ voices become hoarse due to the growth of the voice box, leading to the appearance of an Adam’s apple.

Q6: What is the growth of facial hair in boys a sign of?
Ans: The growth of facial hair in boys is a sign of puberty and the transition to adulthood.

Q7: What is menstruation, and when does it start?
Ans: Menstruation is the discharge of blood from the body, starting around puberty in girls.

Q8: How often does the menstrual cycle typically occur?
Ans: The menstrual cycle generally occurs every 28-30 days.

Q9: What are the two main emotional changes during adolescence?
Ans: Mood swings and increased sensitivity.

Q10: What is a common health issue faced by girls during adolescence?
Ans: Acne, caused by increased oily secretions from the skin.

Q11: What are some examples of secondary sexual characteristics in girls?
Ans: Development of breasts and widening of hips.

Q12: What can help improve reproductive health in adolescent girls?
Ans: A balanced diet, proper hygiene, and the use of sanitary pads during menstruation.

Q13: What should be avoided to ensure good health during adolescence?
Ans: Harmful substances such as tobacco, alcohol, and drugs.

Q14: What is the role of hormones in adolescence?
Ans: Hormones regulate physical and emotional changes and control growth and development.

Q15: What physical change occurs in boys’ bodies that is different from girls?
Ans: The development of a moustache and beard.

Q16: What is the importance of exercise during adolescence?
Ans: Regular exercise helps maintain physical and mental health, builds stamina, and boosts mood.

Q17: What is a good source of calcium for adolescents?
Ans: Milk, cheese, and paneer.

Q18: What is the significance of iron in adolescent girls’ diet?
Ans: Iron is important for the formation of blood and to prevent anaemia.

Q19: What is the ?
Ans: It is a campaign to raise awareness about avoiding substance abuse.

Q20: How can adolescents ensure responsible social media use?
Ans: By being respectful, protecting privacy, and avoiding sharing personal photos with strangers.

Q1: Is cooking food a desirable change?
Ans: Yes, it is a beneficial change.

Q2: What is added to steel to make it stainless?

Ans: Stainless steel is made by mixing iron with carbon and metals like chromium, nickel, and manganese.

Q3: Can physical changes be reversed?
Ans: Yes, like freezing water.

Q4: What is a chemical change?

Ans: A change, in which a new substance with different properties is formed, is known as a chemical change.

Q5: A change, in which a new substance with different properties is formed, is known as a _________________

Ans: Chemical change

Q6: What is the fire triangle?
Ans: The three requirements for combustion: fuel, oxygen, and heat.

Q7: What is erosion?
Ans: The movement of rocks, soil, or sediments by wind or water.

Q8: State the two important conditions for rusting.

Ans: Presence of water and presence of oxygen

Q9: What is weathering?
Ans: The breakdown of rocks into smaller pieces through physical or chemical processes.

Q10: What is the ignition temperature?
Ans: The minimum temperature at which a substance catches fire.

Q11: What is melting?

Ans: Melting is the process of turning a solid to a liquid.

Q12: Name the process by which water molecules continuously change to vapour.

Ans: Evaporation

Q13: What is an irreversible change?
Ans: A change that cannot be undone, like burning wood.

Q14: What is bioluminescence?
Ans: Light produced by living organisms, like fireflies, through a chemical change.

Q15: A medicine is the end product of the chain of ________________________

Ans: Chemical reaction

Q16: Condensation of steam is a chemical process or physical change?

Ans: Physical change

Q17: Cutting of log of wood into pieces is a chemical process or physical change?

Ans: Physical change

Q18: Name the two methods by which rusting of iron can be prevented.

Ans: By painting or greasing and by galvanizing with Zinc

Q1: What is the property that allows metals like gold to be stretched into thin wires?
Ans: Ductility.

Q2: What items do ironsmiths generally make?
Ans: Flat pans, buckets, tongs, spades, axes, trowels, and rakes.

Q3: What material is mainly used to make these items?
Ans: Iron metal.

Q4: What is used to heat the iron in the furnace?
Ans: Coal.

Q5: What is the property that allows metals to be beaten into thin sheets?
Ans: Malleability.

Q6: Which metal is the most malleable?
Ans: Gold.

Q7: What happens to metals like copper and aluminum when beaten with a hammer?
Ans: They flatten.

Q8: What is the name of the process when metals break into pieces?
Ans: Brittle behavior.

Q9: What does ductility allow metals to do?
Ans: Be drawn into wires.

Q10: Which metal is used for making electric wires?
Ans: Copper.

Q11: What is the ringing sound produced by metal called?
Ans: Sonority.

Q12: What property of metals makes them good for cooking vessels?
Ans: Conduction of heat.

Q13: What is the term for the process when iron gets damaged by exposure to air and water?
Ans: Rusting.

Q14: What is the brown deposit formed on iron due to rusting called?
Ans: Rust.

Q15: Which metal reacts vigorously with water and is stored in kerosene?
Ans: Sodium.

Q16: What is the nature of the oxide of magnesium?
Ans: Basic.

Q17: What type of reaction occurs when magnesium burns in air?
Ans: It forms magnesium oxide.

Q18: What is the purpose of applying a protective layer of zinc on iron?
Ans: To prevent rusting.

Q19: Which non-metal is essential for respiration?
Ans: Oxygen.

Q20: What is formed when sulfur reacts with oxygen?
Ans: Sulfur dioxide.

Q1: Circuit diagram is a simplified conventional pictorial representation of an_______________

Ans: Electrical circuit

Q2: A circuit diagram uses standard symbols for electric components. True/ False.

Ans: True.

Q3: Define electric circuit.

Ans: A closed path formed by connecting electrical components allows electric current to flow. This arrangement is known as an electric circuit.

Q4: What is a cell holder?

Ans: A compartment that holds two or more cells together to form a battery is called a cell holder.

Q5: The combination of two or more cells is called a __________________.

Ans: Battery

Q6: A circuit is said to be open circuit or complete when current flows through it. True/ False.

Ans: False

Q7: What is a battery?

Ans: A combination of two or more cells connected together is called a battery. It is formed by connecting the positive terminal of one cell to the negative terminal of another.

Q8: The symbol for a battery is

a. 

b. 

c. 

d. None of These

Ans:  C

Q10: Draw the symbol for an electric bulb in an electric circuit.

Ans:  Symbol of Electric bulb​

Q9: What is a circuit diagram?

Ans: A circuit diagram is a simplified representation of an electrical circuit using symbols to depict various components.

Q10: Why do we use copper wires in electrical circuits?

Ans: Copper is a good conductor of electricity, which allows the current to flow easily through the wires.

Q11: A Longer line in the symbol for a cell represents its ——- terminal.

Ans: Positive

Q12: What is an electric circuit?

Ans: Electric Circuit: The closed path in which electric current flows.

Q13: What happens when the current is switched ‘on’ in a room heater?

Ans: It becomes red hot and gives out heat.

Q14: Would any of the bulbs glow when the switch is in the ‘OFF’ position in a circuit?

Ans: No, the bulb will not glow when the switch is “OFF” because there is no closed circuit for current to flow.

Q15: What type of electricity is used in homes and industries?
Ans: Alternating Current (AC).

Q16: What happens if the filament in an incandescent lamp breaks?
Ans: The lamp stops glowing because the circuit is broken.

Q17: How does a torchlight produce light?
Ans: By passing current through a lamp powered by electric cells.

Q18: What is the purpose of using insulators in circuits?
Ans: To prevent electric shocks and ensure safety.

Q19: What material is used to make the body of most electric cells?
Ans: Metal.

Q20: What direction does current flow in a circuit?
Ans: From the positive terminal of the cell to the negative terminal.