Q31. A small balanced pointer in a compass always points to
(a) south-north
(b) east-west
(c) north-south
(d) west-east
Answer: (c)
Explanation: As the earth has a magnetic field and the pointer in a compass is magnetic, its needle aligns itself with the horizontal component of the earth’s magnetic field. This exerts a torque on the needle pulling one pole of the needle approximately towards the earth’s north magnetic pole and the other towards the south magnetic pole. So, the small balanced pointer always points to the north-south.
Q32. If a satellite is orbiting our earth with a constant speed of 7780 m/s, then this implies the satellite is
(a) Moving with uniform velocity
(b) At rest
(c) Moving with no acceleration
(d) In accelerated motion
Answer: (d)
Explanation: The satellite is orbiting the earth with a constant speed of 7780 m/s. We know that in a uniform circular motion, the direction of an object changes continuously, so the velocity is changing and it is in accelerated motion.
Q33. In which of the following cases of motion, are the distance moved and the magnitude of displacement equal?
(a) The moon is revolving around the earth.
(b) The pendulum is moving to and fro.
(c) The car is moving in a circular motion.
(d) The boy is running on a straight road.
Answer: (d)
Explanation: An object in circular motion has zero displacements but covers some distance. For example, the moon revolving around the Earth or a car in a circular motion will have zero displacements as they start and end at the same point but do cover some distance.
The movement of the pendulum is periodic. So, in this case, also, the displacement is zero, but it has covered some distance.
If a boy is running on a straight road, his initial and final positions will be different, so his displacement magnitude and distance covered will be the same.
Q34. Read the given statements:
The motion of a projectile follows a curved path.
I. A player making a long-jump is an example of
II. horizontal motion.
Ill. Circular motion is a good example of two-dimensional motion.
Which of the statements given above are correct?
(a) Only I and II
(b) Only II and III
(c) Only I and III
(d) All I, II and III
Answer: (c)
Explanation: Projectile motion is a form of motion in which an object or a particle (called a projectile) is thrown near the earth’s surface, and it moves along a curved path under the action of gravity only. Show in the following figure, a player making a long jump exemplifies projectile motion and not horizontal motion.
Q35. Compost is rich in
(a) Organic nutrients
(c) Phosphorous
(b) Potassium
(d) Nitrogen
Answer: (a)
Explanation: Compost is a mixture of decaying matter such as plant remains, animal waste, leftover food, etc. and is rich in organic nutrients.
Q36. Identify the odd one out.
(a) Galvanometer
(b) Voltmeter
(c) Ammeter
(d) Barometer
Answer: (d)
Explanation: Galvanometer, ammeter and voltmeter are all used to measure either amount or direction of electric current, while barometer is an instrument used to measure atmospheric pressure.
Q37. “A fuse is rated 12A.” What does it mean?
(a) It will work if the current is 12A.
(b) It will not work if the current is less than 12A.
(c) It will melt if the current exceeds 12A.
(d) It has a potential difference of 12 volts.
Answer: (c)
Explanation: A fuse is used to protect a circuit from the overloading of current. If a circuit has it is currently going over 12A, the fuse with the 12A rating will be broken, thus averting the overheating of the circuit and the possibility of having a fire because of short-circuiting.
Q38. Two shots are fired from a canon at an interval of 13 seconds, but a person approaching the place heard the sound of the second shot 12 seconds after the first. Find the speed of the person if the speed of sound is 330 m/s.
(a) 18 m/s
(c) 30 m/s
(b) 27 m/s
(d) 36 m/s
Answer: (b)
Explanation: Here, Distance travelled by the person in 12 seconds = Distance travelled by sound in 1 second
Let v be the speed of the person.
∴ v × 12 = 330 × 1
⇒ v = 330/12 = 27 m/s
Q39. A car is going in the northeast direction. If the speed of the car is increased from 54 km/h to 90 km/h in 4 seconds, then what is its acceleration?
Q40. The table given below shows the odometer reading of a car recorded at different times of journey.
Time
Odometer Reading (in km)
2:00 p.m.
24638
2:30 p.m.
24671
3:00 p.m.
24716
3:30 p.m.
24756
4:00 p.m.
24800
The average speed of the car for the whole journey is
(a) 72 km/h
(c) 22.5 m/s
(b) 81 m/s
(d) 64 km/h
Answer: (c)
Explanation: Average speed = $\frac{Total\,\,distance}{Total\,\,time}$
Total distance = 24800 – 24638 = 162 km
Total time = 2 hours
∴ Average speed = 162/2 = 81 km/h = $81\times \frac{5}{18}$ = 22.5 m/s
Q41. A person covers a distance of 150 km at a speed of 30 km/h and then a distance of 75 km in 2.5 hours. He returns to the starting point at a speed of 60 km/h in 1.5 hours. Find the average speed of the person.
(a) 39 km/h
(b) 20 m/s
(c) 35 km/h
(d) 12 m/s
Answer: (c)
Explanation: Total distance = 150 + 75 + 60 × 1.5 = 315 km
Total time = $\frac{150}{30}$ + 2.5 + 1.5
= 9 hours
Average speed = $\frac{Total\,\,distance}{Total\,\,time}$
= 315/9 = 35 km/h
Q42. A cuboid of length 20 cm, breadth 15 cm and height 12 cm is placed on a table. If the mass of the cuboid is 60 kg, then find the pressure exerted by it on the table. (Take g = 9.8 m/s2)
(a) 19600 Pa
(b) 18450 Pa
(c) 16300 Pa
(d) 21600 Pa
Answer: (a)
Explanation: Force exerted by the block on the table
Q43. Which of the following are denitrifying bacteria
(a) Nitrosamines and Clostridium
(b) Nitrobacteria and Pseudomonas
(c) Rhizobium and Clostridium
(d) Pseudomonas and Clostridium
Answer: (d)
Explanation: Pseudomonas and Clostridium are denitrifying bacteria. Roles of Nitrosomonas, Nitrobacter, and Rhizobium are nitrogen-fixing.
Q44. Which of the following statements is not correct?
(a) Forests protect the soil from erosion.
(b) Plants and animals in a forest are not dependent on one another.
(c) Forests influence the climate and water cycle.
(d) Soil helps forests grow and regenerate.
Answer: (b)
Explanation: Plants and animals in a forest are dependent on each other. This is true for any ecosystem.
Q45. What is special about the bryophyllum plant?
(a) It is a very tall plant.
(b) It grows in marshy land.
(c) It can propagate through its leaves.
(d) It is bushy and thorny.
Answer: (c)
Explanation: Bryophyllum can propagate through its leaves. Several bryophyllm species are economically important for causing cardiotoxic effects.
Q46. Rayon is different from synthetic fibres because
(a) Its fibres can also be woven like those of natural fibres
(b) It is cheap, light and long-lasting
(c) It is obtained from wood pulp
(d) It has a silk-like appearance
Answer: (c)
Explanation: Unlike most synthetic fibres (which are petrochemical compounds), rayon is obtained from wood pulp. Like any synthetic fibres, it is light, durable, and cheap, can be easily woven and has a silky appearance.
Q47. A pair of minerals required by the body in a large amount as compared to other minerals is
(a) Sulphur and iron
(b) Calcium and iodine
(c) Sodium and potassium
(d) Phosphorus and molybdenum
Answer: (c)
Explanation: Minerals like vitamins are protective foods. Some of the minerals required in large quantities are calcium, phosphorus, sodium, potassium, sulphur, chloride, and magnesium.
Q48. It is not possible to kill viruses with the help of antibiotics because
(a) They are non-living
(b) They have very few biochemical processes of their own
(c) They are the smallest living organisms
(d) Their DNA multiplies very fast
Answer: (b)
Explanation: Viruses are active only inside the living cells of their host. Though they are the smallest and their DNA multiplies fast in host cells, the reason why they don’t respond to antibiotics is that they have very few biochemical processes of their own.
Q49. Which of the following identified indicators for the assessment of science does predict, making hypotheses and inferences belong to?
(a) Analysing
(c) Classification
(b) Explanation
(d) Experimentation
Answer: (a)
Explanation: Predicting, making hypotheses and inferences belong to the analysing indicator for the assessment of science.
Q50. Which of the following responses of a student shows that he has achieved a good level of indicator of observation and recording?
(a) Giving reasons behind the spoilage of food
(b) Drawing and labelling different parts of a bicycle
(c) Making pots and different ornaments with clay
(d) Expressing his opinions on pumping out of water
Answer: (b)
Explanation: Under the indicator of observation and recording, a child can report, narrate, draw and label the pictures, make tables and maps, etc.
Q51. Which of the following is not the component of 5 Es?
(a) Engage
(b) Explore
(c) Explain
(d) Estimate
Answer: (d)
Explanation: The 5 Es are an instructional model of learning science that follows a constructivist approach. Engage, explore, explain, elaborate and evaluate are five important Es in this model of learning.
Q52. Which is the first step of preparing a question paper?
(a) Preparing the design
(b) Writing the questions
(c) Preparing the blueprint
(d) Writing the marking scheme
Answer: (a)
Explanation: The proper sequence of preparing a question paper is -preparing the design, preparing the blueprint, writing the questions, editing the question paper and finally writing the marking scheme.
Q53. The purpose of asking, If the earth is round like a globe, how is it that we do not fall off?’ from students is to
(a) Promote imaginative and thinking skills of students
(b) Assess students on knowledge about the earth
(c) Make students understand the shape of the earth
(d) Promote the practical skills in students
Answer: (a)
Explanation: The purpose of asking such questions is to promote imaginative and thinking skills in students while they get involved in exploring the answers for these questions.
Q54. Which of the following is the most essential component of the preparation for the field visit?
(a) Asking students to carry a notebook and a pencil
(b) Asking students to carry a water bottle and some food to eat
(c) Making arrangements for assistant teachers and caretaker
(d) Grouping students and sharing with them the plan about the scheduled visit in the form of a prepared structured format activity sheet
Answer: (d)
Explanation: Preparing a structured activity sheet (including information of the places to be visited and things to be observed there) and discussing it with students, before the visit will give students enough time to do their own preparation and research about the place for meaningful learning. One of the purposes of a field trip is that students learn from hands-on experience, correlating with what they have read, heard or discussed in the classroom.
Q55. Why is it important to give space to the children in the teaching-learning process?
(a) Students differ in their level of thinking.
(b) Some students like to talk less than others.
(c) Students get irritated with the more attention of the teacher towards them.
(d) Some students show no sign of improvement even after good attention.
Answer: (d)
Explanation: Students in a class are at different levels of thinking. It is important to give them space to explore their own ideas so that they can learn by doing themselves.
Q56. The concept of comprehensive under CCE aims at
(a) Long-form of assessment
(b) Assessment of half of the syllabus
(c) Assessing both scholastic and non-scholastic areas
(d) Assessing all the students on all indicators quarterly
Answer: (c)
Explanation: Comprehensive refers to both scholastic and non-scholastic areas of a student’s growth. According to the theory behind making the school-based evaluation process comprehensive, the function of a school is not only to build the cognitive capacities of a student but also to develop his non-cognitive abilities. This can be ensured when the overall evaluation procedure of the school is conducted in a comprehensive way.
Q57. Which one of the following should not be done by a science teacher while assessing her students?
(a) Record information in the light of the students learning potential
(b) Focus only on a few aspects of the students’ work
(c) Write qualitative statements about the student’s Work
(d) Compare with previous assessment record of the students
Answer: (b)
Explanation: Assessment is a process by which teachers evaluate the students’ knowledge and other educational skills or abilities. If the teacher focuses only on a few aspects of a student’s work, it will be considered a biased assessment because it does not include all the domains of that student’s skills or abilities.
Q58. ‘Community is an important teaching-learning resource because
(a) It is an easily available resource
(b) It comprises wise and elderly people
(c) It provides learning opportunities in a real setting
(d) It is a very inexpensive resource
Answer: (c)
Explanation: ‘Community develops the socio-cultural aspects within students because in this method all students cooperate with each other. In this method, a student acts as a teacher and all others as students. It provides learning opportunities in a real setting in the absence of a teacher.
Q59. Which of the following is the motive of inclusive education?
(a) Learning majorly in group activities
(b) Teaching similar chapters in the same term
(c) Learning of all subjects in an integrated manner
(d) Allowing students with some disabilities to attend the class alongside peers
Answer: (d)
Explanation: The aim of inclusive education is to let students learn together in a similar environment regardless of their differences in abilities (physical or mental), language, culture, age, gender, caste or other forms. It results in better learning outcomes.
Q60. How does slogan writing on any chosen theme help students?
(a) Reducing some academic pressure through such activities
(b) Increasing the desire for winning in competitions
(c) Increasing the creativity along with awareness
(d) Bringing more fun in the school time age I English
Answer: (c)
Explanation: Slogan writing on any theme such as conservation of forest or scarcity of water helps in increasing the creativity in students along with bringing awareness of the environmental problems and concerns to solve them.
