Question 1 :
What product is obtained when charcoal or coal burns in air?
Question 2 :
Two glass jars A and B are filled with carbon dioxide and oxygen gases, respectively. In each jar a lighted candle is placed simultaneously. In which jar will the candle remain lighted for a longer time?
Question 3 :
Is it True or False that water is the best extinguisher for fires involving electrical equipment?
Question 6 :
The substance expected to have the highest ignition temperature out of the following is
Question 7 :
The calorific value of a fuel is expressed in a unit called
Question 10 :
On placing an inverted tumbler over a burning candle, the flame extinguishes after some time. This is because of non- availability of
Question 11 :
Iqbal has to push a lighter box and Seema has to push a similar heavier box on the same floor. Who will have to apply a larger force?
Question 13 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d0daf59b460d7261f376.PNG' />
From the above figure, if you tie a string around a brick and pull it by spring balance and then wrap a polythene on it and repeat the activity, will the spring balance measurement show any difference?
Question 14 :
We have two identical metal sheets. One of them is rubbed with sand paper and the other with ordinary paper. The one rubbed with sand paper shines more than the other due to which of the following reasons?
Question 15 :
How do objects overcome the force of friction exerted by fluids on them?
Question 17 :
In fact, when a machine is operated, heat generated causes much wastage of _________.
Question 21 :
What is the angle of incidence of a ray if the reflected ray is at an angle of $90^{\circ}$ to the incident ray?
Question 22 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d07cf59b460d7261f2ff.jpg' />
In the above figure, a tiny mirror M is fixed on a piece of cardboard placed on a table. The cardboard is illuminated by light from a bulb. The position of eye with respect to position of bulb is shown in the figure as A, B, C and D. ln which position mirror will be visible?
Question 24 :
Mention whether regular or diffused reflection will take place when a beam of light strikes on Mirror?
Question 25 :
The incident ray, the normal at the point of incidence and the reflected ray all lie in the same plane. This law is known as ____________ ?
Question 27 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d0faf59b460d7261f3a0.PNG' />
Refer to the above figure. Boojho stands at A just on the side of a plane mirror as shown in figure. Can he see the image of objects situated at P, Q and R?
Question 28 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d07df59b460d7261f301.jpg' />
A small hole P is made in a piece of cardboard as shown in the above figure. The hole is illuminated by a torch. The pencil of light coming out of the hole falls on a mirror. At which point should the eye be placed so that the hole can be seen?
Question 29 :
After striking the mirror, the ray of light is reflected in another direction. The light ray, which strikes any surface, is called ________ ?
Question 31 :
What is the central dense round body in the centre of the cell called?
Question 32 :
Which of these are the differences between plant and animal cell?
Question 35 :
An organism with billions of cells begins life as ______ which is the fertilised egg.
Question 36 :
Which of the following statements are true for eukaryotic cells?
(i)They do not have a nuclear membrane.
(ii)They have a well organised nucleus.
(iii)They have a nuclear membrane.
(iv)Blue green algae are eukaryotic cells.
Question 41 :
Since new individuals develop from the buds in hydra, this type of asexual reproduction is called _________.
Question 42 :
Stages in the life cycle of silkworm are given below. Write them in sequential order. Pupa, Silkworm, Egg, Silkmoth.
Question 44 :
Which of the following statements about reproduction in humans is correct?
Question 47 :
Human egg has a head, middle piece and tail. TRUE or FALSE?
Question 48 :
The female reproductive organs are a pair of ovaries, _________ and the uterus
Question 49 :
Among human being, cow, dog and hen. Hen is odd one out. Choose the correct reason for this.
Question 50 :
Egg laid after fertilisation is made up of a single cell.
Question 51 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d050f59b460d7261f2c8.PNG' />
In the above image, observing that the bulb does not glow in the circuit shown in A, Boojho changed the circuit as shown in B. He observed deflection in the magnetic compass. Why did the bulb not glow in A?
Question 52 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d051f59b460d7261f2c9.PNG' />
In the above image, observing that the bulb does not glow in the circuit shown in A, Boojho changed the circuit as shown in B. He observed deflection in the magnetic compass. What will be observed if the number of cells are increased in the circuit shown in B?
Question 54 :
When electric current is passed through a conducting solution, there is a change of colour of the solution. This indicates
Question 55 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d053f59b460d7261f2cb.PNG' />
In the above image, observing that the bulb does not glow in the circuit shown in A, Boojho changed the circuit as shown in B. He observed deflection in the magnetic compass. What would be the effect of increase in the number of turns in the coil wound around the magnetic compass in B?
Question 56 :
Electroplating of ______________ is done on objects like water taps and cycle bell to give them a shiny appearance.
Question 58 :
When electric current is passed through a conducting solution, there is a change of colour of the solution. This indicates
Question 59 :
Boojho’s uncle has set up an electroplating factory near his village. He should dispose off the waste of the factory
Question 60 :
Small amount of a mineral salt present naturally in water makes it a ____________ of electricity.
Question 61 :
Naphthalene balls used to repel moths and other insects are obtained from -
Question 62 :
Now a days, ______ is used as a source of heat rather than light.
Question 63 :
When heated in air, coal burns and produces mainly _______ gas.
Question 67 :
Petrol and diesel are obtained from a natural resource called _____ .
Question 68 :
Natural fuels formed from the dead remains of living organisms (fossils) are known as fossil fuels. TRUE or FALSE ?
Question 70 :
Coal tar is a mixture of various substances. State true or false.
Question 71 :
State true or false: Force of gravity act on dust particles
Question 72 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d06af59b460d7261f2e7.PNG' />
In the above, image, A water tank has four taps fixed at points A, B, C, D is shown. The water will flow out at the same pressure from taps
Question 73 :
Two thermocol balls held close to each other move away from each other. When they are released, name the force which might be responsible for this phenomenon
Question 74 :
Fruits detached from a tree fall down due to force of gravity. We know that a force arises due to interaction between two objects.Which of the following is(are) the objects interacting in this case?
Question 75 :
A gas filled balloon moves up. Is the upward force acting on it larger or smaller than the force of gravity?
Question 76 :
A girl is pushing a box towards east direction. In which direction should her friend push the box so that it moves faster in the same direction?
Question 78 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d06bf59b460d7261f2e9.PNG' />
In the above image, a man with a parachute is shown. Name the force which is responsible for his downward motion?
Question 79 :
A chapati maker is a machine which converts balls of dough into chapati’s. What effect of force comes into play in this process?
Question 80 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d068f59b460d7261f2e5.PNG' />
In the above image, when the circuit is completed, the hammer strikes the gong. Which of the following force is responsible for the movement of hammer?
Question 81 :
The power of an earthquake is expressed in terms of a magnitude on a scale called
Question 84 :
The seismic waves are recorded by an instrument called the _________
Question 87 :
The weather department has predicted that a thunderstorm is likely to occur on a certain day. Suppose you have to go out on that day. Would you carry an umbrella?
Question 90 :
An earthquake measures 3 on the richer scale. Is it likely to cause much damage?
Question 91 :
Removal of the top layer of the soil exposes the lower, hard and rocky layers. This soil has less humus and is less fertile. Gradually the fertile land gets converted into deserts. It is called __________?
Question 92 :
A place reserved for wild life where they can freely use the habitats and natural resources is known as?
Question 93 :
Endemic species are those species of plants and animals which are found exclusively in a particular area. Is it TRUE OR FALSE?
Question 95 :
In our country, large patches of forests are being cleared for cultivation of crops. The environmental impact of such a practice will lead to ________.
Question 96 :
What affect the natural habitat of endemic species and endanger their existence?
Question 97 :
What is that part of the earth in which living organisms exist or which supports life?
Question 100 :
The animals found in a particular area is termed as ______ ?
Question 102 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d0def59b460d7261f37b.JPG' />
From the above image, Is the above equation correct if saloni took a piece of burning charcoal and collected the gas evolved in a test tube?
Question 103 :
Why Immersion rods for heating liquids are made up of metallic substances?
Question 104 :
Phosphorus is a very reactive non-metal. It catches fire if exposed to air, to prevent the contact of phosphorus with atmospheric oxygen, it is stored in _______
Question 105 :
Generally metallic oxides are basic and non-metallic oxides are acidic in nature. Solution of which of the following oxides in water will change the colour of blue litmus to red?
Question 107 :
Generally, metals are good conductors of heat and electricity but non-metals are poor conductors.
Question 109 :
On burning, metals react with oxygen to produce metal oxides which are basic in nature. Non-metals react with oxygen to produce non- metallic oxides which are acidic in nature.
