KTET Paper 2: Science and Mathematics Test - 9 - KTET MCQ

Given:
∠ABC = 90° and ∠DCB = 90°
AB = DC (given)
Calculation:
AB = DC (given)
∠ABC = ∠DCB = 90° 
BC = BC (Since the line segment BC is common to both triangles)
By the SAS Congruence Property,  ΔABC ≅ ΔDCB

A concept map provides a concrete record of the connections perceived by the students, and thus it indicates how the student’s knowledge is organized and interconnected. Mapping is the creative process of organizing content and can be used in planning lessons, learning, and developing mathematical literacy and spatial thinking.

• A reddish-brown deposit called rust, forms over a piece of iron when it is exposed to moist air for some time. Rust is hydrated iron (III) oxide (Fe₂O₃.xH₂O).
• When iron metal is exposed to air for a long time, it oxidises and forms a reddish-brown colour iron oxide on its surface.
• The iron rusting formula is 4Fe + 3O₂ + 6H₂O → 4Fe(OH)₃.

To be divisible by 11,
(9 + 8 + 7) - (y + 0 + 1) should be a multiple of 11.
(24 - y - 1) should be a multiple of 11.
(23 - y) should be a multiple of 11.
So, y = 1

The centrosome is a microtubule-organising centre found near the nuclei of animal cells. It contains a pair of centrioles, two structures that lie perpendicular to each other. Each centriole is a cylinder of nine triplets of microtubules.

829030000 expressed in the standard form is 8.2903 x 10⁸
Now, 8.2903 x 10⁸ = k x 10ⁿ
Thus, k = 8.2903, n = 8
k + n = 8.2903 + 8 = 16.2903
Thus, option (2) is correct.

Given:
Number of sides = 12
Formula Used:
Number of diagonal = n(n−3)/2
Where n is the number of sides of a polygon.
Calculation: 
Number of diagonal = n(n−3)/2
⇒ Number of diagonal = 12(12−3)/2
⇒ Number of diagonal = 54 diagonals can be drawn in a polygon having 12 sides.
The correct option is 2 i.e. 54

Resistors in Parallel: 

• Both of a resistor's terminals are linked to the respective terminals of another resistor or resistor.
• In this, the circuit current can take more than one path as there are multiple paths for the current.
• The current may not be the same in the parallel network.
• It has a common voltage across the network.

​CALCULATION:
The reciprocal of the equivalent resistance (R_p) of a group of resistances joined in parallel is equal to the sum of the reciprocals of the individual resistances that is 
​1/R_p = 1/R₁ + 1/R₂ + 1/R₃ + ......1/R_n  
= 1/12 + 1/12 + 1/12 + 1/12 
= 4/12 = 1/3 
R_p = 3 Ω
Hence, the total equivalent resistance of the circuit is 3 Ω.

• Blood is red in colour due to the presence of Haemoglobin.
• Haemoglobin is the iron-containing oxygen-transport metalloprotein in the red blood cells of all vertebrates (with the exception of the fish family Channichthyidae) as well as the tissues of some invertebrates.
• Haemoglobin present in RBC carries or transports oxygen from the lungs to the tissues, whereas it also carries forward carbon dioxide from the tissues to the lungs.
• Haemoglobin is a fused protein in which a protein called globin and an iron ion are found.

Non-metallic oxides dissolve in H₂O to give acidic solution which turns blue litmus red. Therefore, the correct answer is CO₂.

The mineral pyrite, or iron pyrite, also known as fool's gold, is an iron sulphide with the chemical formula FeS₂.

Given:
Cost of 90 articles = Rs 5400
Formula used:
Gain = SP – CP
Loss = CP – SP
Loss % = (Loss/CP) × 100
Gain % = (Gain/CP) × 100
Calculation:
Cost of 1 article = 5400/90 = Rs. 60
Total cost price of 70 articles = 70 × 60 = Rs. 4200
Profit earned = 5040 – 4200 = Rs. 840
% profit = (840/4200) × 100 = 20%
∴ There is a gain of 20%.

Conduction: 

• The heat transfer through direct physical contact is known as conduction.
• Heat transferred from one end to other end is called conduction. 
• Heat transfer through conduction can only happen in conductors of heat like iron, copper etc. 
• Heat transfer do not take place across insulators like wood, plastic etc. 

Radiation: 

• When electromagnetic radiation is emitted or absorbed to transfer the heat or When heat is transferred in the form of electromagnetic waves is known as radiation.
• Electromagnetic radiation includes microwaves, radio waves, infrared radiation, visible light, ultraviolet radiation, gamma rays, and X-rays.
• The method does not require any medium so heat from the sun reaches us by this method.

Convection

• It is heat transfer by the movement of its molecules.
• It occurs only in fluids (liquid and gas) not in solids because solid particles can not move from one place to another.
• For example, in a pot boiling water on the stove, or in thunderstorms, where hot air rises up to the base of the clouds.

• Battery acid is sulfuric acid.
• It has been diluted with water to achieve a 37% concentration level.
• Car or automotive battery acid in water is 30-50% sulfuric acid (H₂SO₄).

The number of lines of symmetry in a regular polygon is equal to the number of sides.

For pH = 3, [H⁺] = 10^-3
For pH = 6, the [H⁺] required = 10^-6

Therefore, the sample has to be diluted 10³ times.

One Astronomical Unit is now defined as exactly 149597870700 metres.

Mathematics is a study of patterns, numbers, geometrical objects, data, and information. It deals with data analysis, integration of various fields of knowledge, deductive and inductive reasoning, and generalizations.

• It involves the mathematization of thoughts that develops through mathematical reasoning which consists of abstract statements and their proofs.
• Mathematical reasoning includes the critical and analytical thinking of an individual that will help in dealing with abstractions of mathematics.

• Most nonmetals do not react with air at room temperature.
• But, White phosphorus is the only nonmetal that reacts with air to form its oxide by burning.
• Phosphorus is a non-metallic element.
• White phosphorus is the form that occurs most commonly at room temperature.
• It is very reactive and combines with oxygen in the air very easily.
• It catches fire spontaneously when exposed to air.
• In chemical laboratories, it is stored underwater to avoid burning.

Scientific Processes:  All processes in science are done with specific purpose, evidences are collected with reliable and valid methods, and they are examined critically by controlling different variables.

This is the correct answer. The student is not able to understand the concept of linear equations properly.

The formal steps involved in the approach are as listed below:
i. Introduction/Motivation
ii. Presentation
iii. Comparison and association
iv. Generalisation
v. Application
vi. Recapitulation

An explorer is a person who travels and investigates little known places to gain new knowledge.

Problem-solving is a mental process and is part of the larger problem process that includes problem finding and problem shaping. It has been defined as a higher-order cognitive process that requires the modulation and control of more routine or fundamental skills.

• Problem-solving is not just about correcting the problem, it is a permanent solution to eliminate the source of the problem so that the problem does not occur again.

• An herbivore is an organism that feeds mostly on plants.
• Herbivores range in size from tiny insects such as aphids to large, lumbering elephants.
• As a result of their plant diet, herbivorous animals typically have mouthparts adapted to rasping or grinding.
• From the following list of animals sheep, grasshoppers and rabbits are the animals that have plants as their diet.
• Hawks are carnivorous, which means they eat animals, not plants.

Diagnostic assessment is the assessment that is conducted along with formative assessment during the instructional process. It is carried out based on the data obtained from formative assessment.

The skillful change in the stimuli is known as the skill of stimulus variation. Just to avoid boredom, it is the teacher's skills to stimulate the students, increase their active participation, enthusiasm and spirit of study. Various stimuli such as movement of the body, gesture, changes in speech, focusing of the feeling, change in the interaction style in the students, pause and change in the order of audio visual aids, etc. are some of them.
Praising the students is NOT one of the components of stimulus-variation skill.

Thermometer should be washed with cold water and not hot water before and after use.

The Project Approach refers to a set of teaching strategies that enable teachers to guide students through in-depth studies of real world topics. This is a merit of this method.