Q 1 – Identify the micro-organism whose nutrition type is shown below :
(a) Food bacteria
(b) Yeast
(c) Fungus
(d)Amoeba
(d)Amoeba
Q 2 – What is the correct direction of flow of electrical impulses ?
Q 3 – If the key in the arrangement taken out (the circuit is made open) and magnetic field lines are drawn over the horizontal plane ABCD, the lines are
(a) concentric circles
(b) elliptical in shape
(c) straight lines parallel to each other
(d) concentric circles near the point O but of elliptical shapes as we go away from it
(c) straight lines parallel to each other
Q 4 – Which of the following are correct structural isomers of butane ?
(a) (i) and (iii)
(b) (i) and (ii)
(c) (ii) and (iv)
(d) (ii) and (iv)
(a) (i) and (iii)
Q 5 – The diagram shows part of the human gas exchange system.
Here, W X , ,Y and Z are?
| Bronchus | Bronchiole | Larynx | Trachea |
(a) | W | X | Z | Y |
(b) | X | W | Y | W |
(c) | Y | Y | X | Z |
(d) | Z | Z | W | X |
Larynx is at the beginning of trachea. After Trachea, bronchi are found hich further branch into bronchioles.
Q 6 – The resistivity does not change if
(a) the material is changed
(b) the temperature is changed
(c) the shape of the resistor is changed
(d) the shape of the resistor is changed
(c) the shape of the resistor is changed
Q 7 – Which of the following pair is incorrect in the given table?
The pair given in the (d) option is wrong because it is a displacement reaction. A displacement reaction occurs because a more reactive element displaces a less active one from a solution of its compounds.
Q 8 – The given diagram is the structure of a/an-
(a) Alimentary canal
(b) Respiratory tract
(c) Nephron
(d) Small intestine
(c) Nephron
Q 9 – An electric kettle consumes 1 kw of electric power when operated at 220 V. A fuse wire of what rating must be used for it?
(a) 1 A
(b) 2 A
(c) 4 A
(d) 5 A
(d) 5 A
Q 10 – For the start of respiration, a living cell requires?
(a) Glucose
(b) Glucose + O2
(c) O2
(d) Glucose + ATP
(a) Glucose
Q 11 – Choose the incorrect statement from the following regarding magnetic lines of field
(a) The direction of magnetic field at a point is taken to be the direction in which the north pole of a magnetic compass needle points.
(b) Magnetic field lines are closed curves.
(c) If magnetic field lines are parallel and equidistant, they represent zero field strength
(d) Relative strength of magnetic field is shown by the degree of closeness of the field lines.
(c) If magnetic field lines are parallel and equidistant, they represent zero field strength
Q 12 – A constant current flows in a horizontal wire in the plane of the paper from east to west as shown in Figure. The direction of magnetic field at a point will be North to South.
(a) directly above the wire
(b) directly below the wire
(c) at a point located in the plane of the paper, on the north side of the wire
(d) at a point located in the plane of the paper, on the south side of the wire.
(b) directly below the wire
Q 13 – In the following circuits (Figure), heat produced in the resistor or combination of resistors connected to a 12 V battery will be
(a) same in all the cases
(b) minimum in case (i)
(c) maximum in case (ii)
(d) maximum in case (iii)
(b) directly below the wire
Q 14 – In Spirogyra, asexual reproduction takes place by
(a) In Spirogyra, asexual reproduction takes place by
(b) division of a cell into two cells
(c) division of a cell into many cells
(d) formation of young cells from older cells
(b) directly below the wire
Q 15 – At the time of short circuit, the electric current in the circuit :
(a) vary continuously
(b) does not change
(c) reduces substantially
(d) increases heavily
(d) increases heavily
Q 16 – Which of the following substances will not give carbon dioxide on treatment with dilute acid?
(a) Marble
(b) Limestone
(c) Baking soda
(d) Lime
(d) Lime
Q 17 – Assertion : A solenoid tends to expand, when a current passes through it.
Reason : Two straight parallel metallic wires carrying current in same direction attract each other.
(a) Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
(b) Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
(c) Assertion (A) is true but reason (R) is false.
(d) Assertion (A) is false but reason (R) is true.
(d) Assertion (A) is false but reason (R) is true.
Q 18 – Assertion : A current carrying conductor experiences a force in a magnetic field.
Reason : The force acting on a current carrying conductor in a magnetic field is due to interaction between magnetic field produced by the current carrying conductor and external magnetic field in which the conductor is placed.
(a) Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
(b) Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
(c) Assertion (A) is true but reason (R) is false.
(d) Assertion (A) is false but reason (R) is true.
b) Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
Q 19 – Assertion : The magnetic field produced by a current carrying solenoid is independent of its length and cross-section area.
Reason : The magnetic field inside the solenoid is uniform.
(a) Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
(b) Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
(c) Assertion (A) is true but reason (R) is false.
(d) Assertion (A) is false but reason (R) is true.
(b) Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
Q 20 – Assertion : In plants, water is transported through phloem.
Reason : It is because sieve tubes are absent in phloem.
(a) Both Assertion and Reason are true and Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
(c) Assertion is true but Reason is false.
(d) Both Assertion and Reason are false.
(d) Both Assertion and Reason are false.
Q 21 – Draw a neat diagram to show the refraction of a light ray through a glass prism and label on it the angle of incidence and angle of deviation.
Q 22 – Pratyush took sulphur powder on a spatula and heated it. He collected the gas evolved by inverting a test tube over it as shown in Figure below :
(a) What will be the action of gas on
(i) dry litmus paper ?
(ii) moist litmus paper ?
(a) Sulfur is a non – metal. Oxides of non metals are acidic. In this case Sulfur dioxide is produced which is acidic.
(i) It will not react with dry litmus paper.
(ii) Blue litmus paper turns red.
Q 23 – What is the cause of peptic ulcer ?
peptic ulcer is caused by imbalance in the rate of gastric juice secretion causes irritation of the mucosal layer of the stomach. This results in poor secretion of mucus that protects the inner lining. Ultimately, the mucosal layer is eroded causing the ulcer.
Q 24 – “Energy flow in a food chain is unidirectional.” Justify this statement.
Sun is the only source of energy. Producers convert solar energy into chemical energy in the form of food. The primary consumers (herbivores) depends on producers for food. According to the energy transfer law, only 10% of energy is transferred from one trophic level to the other. Therefore, the energy that is captured by the producers does not come back to the Sun and the energy transferred to the herbivores does not come back to the producers. It just keeps on moving to the next trophic level in a unidirectional way. That is why the flow of energy in the food chain is always unidirectional.
Q 25 – What are the end products formed during fermentation in yeast ? Under what condition a similar process takes place in our body that leads to muscle cramps ?
The end products formed during fermentation in yeast are ethanol and carbon dioxide. A similar process occurs in the muscles and produces lactic acid during anaerobic respiration in the muscles. Accumulation of lactic acid in the muscle cells lead to muscular cramps.
Q 26 – Which component of white light deviates (i) the least and (ii) the most while passing through a glass prism? State the reason of this difference in deviation.
(i) Least – red
(ii) Most – Violet
Reason : due to the variation in their wavelengths and difference in refractive of the media, the difference in refractive indices of the media, the difference in deviation has taken place.
Q 27 – Mention the three kinds of cells present in blood. Write one function of each.
Blood is made up of plasma and corpuscles. Three kinds of corpuscles are WBC, RBC and blood Corpuscles (RBC) are small biconvex cells that contain Hemoglobin to transport O2 From the lungs to the body cells and CO2 from body cells to the lungs. white blood cells (WBC) – Main function defence of the body against diseases and other infection. Blood platelets are responsible for the clotting of blood during injuries.
Q 28 – Explain the following statements :
(a) Most metal oxides are insoluble in water but some of these dissolve in water. What are these oxides and their solutions in water called ?
(b) At ordinary temperature the surface of metals such as magnesium, aluminium, zinc etc., is covered with a thin layer. What is the composition of this layer ? State its importance.
(c) Some alkali metals can be cut with a knife.
(i) These oxides are called basic oxides and their solutions in water are called alkalis.
(ii) This layer formed is protective oxide layer which prevents the metals from further oxidation.
(iii) Some alkali can be cut with a knife because they are very soft and have low densities.
Q 29 – (a) State the relationship between focal length and radius of curvature of a spherical mirror.
(b) Why is the refractive index of a medium always greater than one ?
(c) A lens has-4 D power. Is the lens concave or convex ?
Q 30 – Larger animals kill the smaller animals in the forest, eat whatever they can, leave the rest in the forest but the forest is never found full of dead animals. What happens to the bodies of these dead animals?
Q 31 – (a) Name the kind of lens that can form;
(i) an inverted magnified image.
(ii) an erect diminished image.
Draw ray diagrams to illustrate your answer in each case.
(b) Draw a ray diagram to show the image formed of an object placed between f and 2f distances from a convex lens.
Q 32 – It is said that, there is a need to put a complete ban on the products containing aerosols. What are aerosols ? Why is there a demand to put a ban on them.
(a) Explain in brief, convex lens is converging in nature.
(b) A convex lens forms a real and inverted image of a needle at a distance of 50 cm from it. Where is the needle
placed in front of convex lens if the image is equal to the size of the object ? Also find the power of the lens.
Aeroslos are the colloidal system of solid or liquid particles in a gas.
Aerosols are the cause of ozone layer depletion which protects us from harmful ultra violet radiations of sun.
Aerosols also affect our health adversely. Inhaling aerosols may cause sneezing coughing, vomiting, diarrhea, slurred speech double vision drowsiness and muscle pain. therefore, there is demand to put ban them.
Q 33 – Differentiate autotrophs hetrotrophs and decomposer and give one example of each.
Heterotrophs: The organisms which cannot makes their own food from the raw materials such as CO2 H2O etc. using sunlight are called hetetrotrophs. Heterotrophs depend on others organisms for their food. All animals including human beings are heterotrophs. heterotrophs are also termed as consumers.
The differences between auto – trophs and decomposers are:
Q 34 – Complete the following reactions :
Q 35 – (a) Use of a condom is beneficial for both the sexes involved in a sexual act.” Justify this statement giving two reasons.
How do oral contraceptive help in avoiding pregnancies ?
What is sex selective abortion? How does it affect a healthy society ? (State any one consequence)
.(a) Use of condom is beneficial for both sexes because:
(i) It helps in spacing children.
(ii) It helps in preventing spread of STDs.
(b) Spermicidal applications by women, vaginal pills or oral contraceptive pills (OCPs) are used. OCPs are hormonal preparations which alter the hormonal level in female body.
(c ) medical termination of pregency (MTP) is a method that should be used only if the foetus has some defect, of if it is life-threatening to the mother. It should not be used as a contraceptive method.
Surgery can also be used for removal of unwanted pregnancies. These may be misused by people why do not want a particular child, as happens in illegal sex-selective abortion of female foetuses. For a healthy society, the female-male sex ratio must be maintained. Because of reckless female foeticides, child sex ratio is declining at an alarming rate in some sections of our society, although prenatal sex determination has been prohibited by law.
Q 36 – (a) For the combination of resistors shown in the following figure, find the equivalent resistance between M and N
(a) State Joule’s law of heating.
(b) Why we need a 5 A fuse for an electric iron which consumes 1 kW power at 220 V?
(c) Why is it impracticable to connect an electric bulb and an electric heater in series?
(a) IN the above digram R1 and R2 are connected in series and R3 and R4 are connected in parallel combination.
(R1 + R2) + 
(b) Joule,s law of heating implies that heat produced in a resistor is (i) directly proportional to the square of current for a given resistance, (ii) directly proportional to resistance and (iii) directly proportional to the time for which the current flows through the resistor.
H = I2 Rt
I = Current
R = Resistance
T = Time taken
(c) For an electric iron which consumes 1 kW electric power when operated at 220 V, a Current of (1000/220) A, i.e., 4.54 A will flow in the circuit. In this case, a % A fuse must be used.
(R1 + R2) +
(d) In a series circuit the current is constant throughout the electric circuit. Thus , it is obviously impracticable to connect an electric bulb and an electric heater in series, because they need currents of widely different values to operate properly.
Q 37 – Sample of four metals P, Q, R and S were taken and added to the following solution one by one. The results obtained have been tabulated as follows.
(i) Which is the most reactive metal ?
(ii) What would you observe if Q is added to a solution of CuSO4. Also, what is the colour change when Q is added to FeSO 4.
Q 38 – Question numbers i – iv are based on the table given below. Study the table and answer the following questions.
(i) What is sex determination?
(ii) What are the sex chromosomes in the males?
(iii) What are the sex chromosomes in the females?
(i) The process by which the sex of a newborn organism is detected is called sex determation.
(ii) The males have two sex chromosomes which are X and Y
(iii) The sex chromosomes in the females are X and X.
Q 39 –A concave lens is thick at the edges and thin at the centre, while a convex lens is thick at the centre and thin at the edges. We can distinguish between a concave lens and a convex lens without touching them. For this keep a book close to a lens and observe the image of the text of the book through the lens. If the letters appear enlarged, then it is a convex lens and if the letters appear diminished then it is a concave lens.
Convex lens converges light rays and hence known as converging lens. Similarly, concave lens diverges light rays and is known as diverging lens. Linear magnification produced by a lens is equal to the ratio of the image distance to the object distance. Power of a lens is defined as the reciprocal of its focal length.
(i) What type of image is always made by a concave lens ?
(ii) If magnification produced by a spherical lens is +0.75, then what is the nature of the lens ?
(iii) What is the power of a convex lens with focal length 80 cm ?
Concave lens always forms virtual, erect and diminished image of an object.
(ii) Here, m = 0.75 (less than 1) so the image formed is smaller then the object or diminished. A virtual ,erect and diminished image can be formed only by a concave lens, so the nature of the lens is concave.
(iii) Power of the convex lens
