KTET Paper 2: Science and Mathematics Test - 7 - KTET MCQ

100% pure gold = 24 carat
50% pure gold = 12 carat = Rs 30,000
∴ 22 carat cost = 30,000 ÷ 12 × 22 = Rs 55,000
Detailed solution
GIVEN:
24 carat gold is hundred percent pure gold.
Price of 50% pure gold is Rs. 30,000
So, price of 1% pure gold = Rs. 600
CONCEPT:
In 22 carat gold pure gold is 22 parts out of 24 parts.
CALCULATION:

Percent of pure gold in 22 carat gold =(22/24)×100% = 91(2/3)%
Since, price of 1% pure gold = Rs. 600
∴ Price of pure gold in 22 carat Gold  = Rs.600 × 91(2/3)%
⇒ Price of pure gold in 22 carat Gold = Rs. 55,000

Mathematics is the study of numbers, shapes, quantities, and patterns. Mathematics is the ‘queen of all sciences’ and its presence is there in all the subjects. It acts as the basis and structure of other subjects. Mathematics is one of the few subjects that have functional, cultural, and disciplinary value. To make Mathematics an instrument of all the three values, it must be taught in an engaging, interesting, and interacting manner.

• Every organism adapts to the environment in which they survive. 
• Polar bears survive in very cold regions due to various adaptation done by it through the process of evolution. 

Polar Bears Adaptation to Climate:

• Polar bears have white fur so that they are not easily visible in the snowy white background.
• To protect them from extreme cold, they have two thick layers of white fur.
• They also have a layer of fat under their skin.
• On warm days, the polar bear goes for swimming. They are good swimmers. 
• Their paws are wide and large, which helps to swim when overheated.

• Apart from this the color of the fur is white, so they can easily hid in snow. 
• This give them protection from predators as well as help them to catch their prey for food. 

So, the correct option is 'All the above.'

There are six lines of symmetry as shown.
Hence, option (4) is correct.

There are compounds made up of the same elements, like carbon monoxide (CO) and carbon dioxide (CO2). Both compounds are made of carbon (C) atoms and oxygen (O) atoms. However, the ratios of carbon and oxygen in each compound are different. This illustrates the law of multiple proportions.

Pollen is a fine to coarse powdery substance comprising pollen grains which are male microgametophytes of seed plants, which produce male gametes (sperm cells). To develop haploid plants through tissue culture, the best choice is pollen grains.

Given:
The ratio of the slant height and radius of right circular cone = 29 : 20
Volume = 4838.4 cm³
Formula used:
Volume of cone = 1/3πr²h
h² = √l² – r²
Calculation:
Let the ratio of the slant height and radius of right circular cone be 29x and 20x respectively
According to the question
h = √l² – r²
⇒ h = √29x² – 20x²
⇒ h = √(841 – 400)x²
⇒ h = √441x²
⇒ h = 21x cm
Now,
Volume of cone = 4838.4 π
⇒ (1/3 × π × 400x² × 21x) = 4838.4 π 
⇒ x³ = (172.8/100)
⇒ x³ = (1728/1000)
⇒ x = 12/10
Now,
The radius = 20x = (20 × 12/10) cm
⇒ 24 cm
∴ The required radius is 24 cm

• Cold-blooded Animals- are animals that cannot regulate their internal body temperature with the change in the environment.
• Warm-blooded animal-A warm-blooded animal, for example, a bird or a mammal, has a fairly high body temperature which does not change much and is not affected by the surrounding temperature.

About Rabbit:

• Oryctolagus cuniculus, scientfic name of rabbit.
• A baby rabbit is called a kit, a female is called a doe and a male is called a buck.
• A rabbit's teeth never stop growing.
• It belongs to the phylum Mammalia, so they are warm-blooded animals.
• Rabbits’ eyes are on the sides of their head, meaning they can see almost all the way around them.

• Hot air is lighter than cold air. 
• If there is a hot temperature in an area, the hot light air goes up. 
• This reduces air and hence reduced atmospheric pressure is created at that area. 
• Now, the empty space formed is occupied by the air coming from high-pressure areas. 
• The flow of air from a high-pressure area to a low-pressure area causes wind.
• The speed of the wind will be more if the pressure difference will be more. 

So, it is clear that the if atmospheric pressure increases, the wind speed will increase. 

a = 6
b = 5 + 5 = 10
c = 6
((a - b + c)/2)² - 2 = 1 - 2 = -1
Thus, option (4) is correct.

Frequency of our household alternating current is 50 Hz.

Frictional force is an example of contact force, while gravitational force, electrostatic force and magnetic force are examples of non-contact forces.

Given:
The length, breadth, and height of a cuboid are 14 cm,11 cm, and 3.5 cm.
Formula used:
The volume of a cuboid = length × breadth × height = l × b × h
Calculation:
The volume of a cuboid = l × b × h
⇒ 14 × 11 × 3.5
⇒ 539 cm³
∴ The volume of a cuboid is 539 cm³.

• The basic solution can turn red litmus to blue.
• Add a few drops of solution from each text tube on litmus paper.
• The distilled water is neutral in nature and thus on adding it to litmus paper there is no color change in litmus paper. 
• With the addition of a few drops of acidic solution on blue litmus paper, the litmus paper turns blue to red.
• With the addition of a few drops of basic solution on red litmus paper, the litmus paper turns red to blue.

Vitamin B2

• ​A deficiency of vitamin B2 can cause skin disorders, hyperaemia (excess blood) and swelling of the mouth and throat, angular stomatitis (sores on the corners of the mouth) and hair loss.
• One of the eight B vitamins that are crucial for human health is vitamin B2, sometimes known as riboflavin.
• Grain, vegetables, and dairy products all contain it. It is essential for digesting food, absorbing other nutrients, and keeping tissues healthy.
• Every vitamin is either fat-soluble or water-soluble. Water-soluble vitamins are transported by the bloodstream, and excess amounts leave the body through urine. 

A number is written in scientific notation(standard form) when a number between 1 and 10 is multiplied by a power of 10.
(14.96 x 10¹⁰) – (3.84 x 10⁸)
=1496 x 10⁸ - 3.84 x 10⁸
= 1492.16 x 10⁸
= 1.49216 x 10¹¹

For the metamorphosis of tadpoles, iodine should be present in water. This is because metamorphosis is brought about by thyroxine hormone that requires the presence of iodine for its production by thyroid gland.

The relative atomic masses of many elements are not whole numbers because there are different isotopes of the elements. The atomic weight is the average based on the proportions that they occur in naturally.

While learning mathematics, children come up with their own naive theories, which needs to be cleaned by the teacher. 

• It is clear from the scenario of Rohit saying that numerator is the same, he is aware of the concept of numerator and denominator.
• While comparing fractions with the same numerator, the fraction which has a smaller denominator is considered as bigger.
• Thus, the answer must be '3/5 is bigger than 3/7'. But Rohit says it in the opposite way. It is because doe not know the concept of resultant magnitude of fractions.

Hence, we conclude that Rohit does not understand the magnitude of fractions.

• Force acting on a unit area is called pressure.
• The pressure increases with increasing depth.
• This is due to the water up above weighing down on the water below.
• Liquid pressure increases as depth increases.
• The pressure is greater on the lower surfaces of the body than on the upper surfaces as the pressure in a fluid increases with depth.
• Pressure and depth are directly proportional to each other.

Scientific method is a method of solving problem scientifically. Training in the method is more important than the acquisition of information. Once the student is trained in the method they will approach all the problems in the same way, even if they are put in a situation which they are quite ignorant of.

• According to Lundberg “Scientific method consists of systematic observation, classification and interpretation of data”.
• Carl Pearson says “The scientific method is marked by the following features: Careful and accurate classification of facts, observation of their co-relation and sequence, and discovery of scientific laws with the aid of creative imagination and their self-criticism."
• Scientific method involves reflective thinking, reasoning and results from the achievement of certain abilities, skills and attitudes.
• It needs continuous training. For continuous appraisal of the scientific method, the teacher should provide such situations and activities as are conducive to its development and training.

Hence, we conclude that Lundberg considered scientific method consists of systematic observation, classification and interpretation of data.

We can encourage the students by organising educational games/programmes in which children feel like speaking. The educational games would motivate the student a lot.

Experiments provide insight into cause-and-effect by demonstrating what outcome occurs when a particular factor is manipulated. Experiments vary greatly in goal and scale, but always rely on repeatable procedure and logical analysis of the results.

This will be considered as the most suitable option because there are more chances of getting different amount of results if we are getting results in percentages as compared to any other option.

Learning objective mean-what should a learner be able to do or do better, after going through an educational programme, that she\he was unable to do or could not do so well before.

• They are the statements of those changes in behavior that are desired as a result of specific learner and teacher activity which is a two-way process.

• The reproductive parts of angiosperms are located in the flower. 
• The different parts of a flower are sepals, petals, stamens and pistil.
• Stamens and pistil are the reproductive parts of a flower that contain germ cells.
• Stamens represent the male reproductive part while the pistil is the female reproductive organ.
• The pistil is present in the centre of a flower and is the female reproductive part.
• It is made of three parts - Stigma, ovary and style.
• The swollen bottom part is the ovary, the middle elongated part is the style and the terminal part which may be sticky is the stigma.

The process of interpreting the world of knowledge to a pupil's mind is called the method of teaching. It helps a teacher to understand "what to teach", "how to teach", "how to approach it".

• It includes both strategies and techniques of teaching and involves the choice of what is to be taught.
• The teacher must be flexible while using teaching methods to encourage the participation of students in the teaching-learning process.​

The teacher has posed this problem in the class, which is a kind of formative assessment. Such kind of assessment is done by the teacher to know what all the students have learnt, and what else is expected from them. The teacher prepares his/her lesson plans accordingly.

The teacher is best advised to find out and explain the cause of failure of the demonstration by involving students.

Science includes only relative truths but not absolute truths. This means that science does not accept philosophical concepts.