This question tests knowledge about the official publications of prominent international scientific organizations. Specifically, it asks for the official journal of the Committee on Space Research (COSPAR).
Correct Option: C) Advances in Space Research is the official journal of the Committee on Space Research (COSPAR). It is a peer-reviewed scientific journal that publishes papers from COSPAR Scientific Assemblies and other related research.
To find the ratio of the areas of two squares given the ratio of their diagonals, we need to establish a relationship between the diagonal of a square and its area. We know that the diagonal of a square can be expressed in terms of its side, and the area of a square can also be expressed in terms of its side. By combining these relationships, we can find the area in terms of the diagonal.
Let the side length of square M be \(s_M\) and its diagonal be \(d_M\). Let the side length of square N be \(s_N\) and its diagonal be \(d_N\).
For any square, the relationship between its side (\(s\)) and its diagonal (\(d\)) is given by the Pythagorean theorem:
\[ d^2 = s^2 + s^2 = 2s^2 \]So, the diagonal is \(d = s\sqrt{2}\). From this, we can express the side in terms of the diagonal:
\[ s = \frac{d}{\sqrt{2}} \]The area (\(A\)) of a square is given by \(A = s^2\). Substituting the expression for \(s\) in terms of \(d\):
\[ A = \left(\frac{d}{\sqrt{2}}\right)^2 = \frac{d^2}{2} \]This formula relates the area of a square directly to its diagonal.
We are given that the ratio of the diagonals of square M and square N is 2:1. So,
\[ \frac{d_M}{d_N} = \frac{2}{1} \]Now, let's find the ratio of their areas, \(A_M\) and \(A_N\):
\[ \frac{A_M}{A_N} = \frac{\frac{d_M^2}{2}}{\frac{d_N^2}{2}} \] \[ \frac{A_M}{A_N} = \frac{d_M^2}{d_N^2} = \left(\frac{d_M}{d_N}\right)^2 \]Substitute the given ratio of diagonals into this equation:
\[ \frac{A_M}{A_N} = \left(\frac{2}{1}\right)^2 = \frac{4}{1} \]Thus, the ratio of their areas is 4:1.
Correct Option: D) 4:1
The question asks to identify which of the given options is NOT a renewable source of energy. To answer this, we need to understand the definition of renewable and non-renewable energy sources.
Correct Option: D) Coal is a fossil fuel formed over millions of years and exists in finite quantities. Once consumed, it cannot be replenished on a human timescale, making it a non-renewable source of energy.
The question asks about the functionality of a serial port. Understanding the basic purpose of any input/output (I/O) port in a computer system is key. Ports are interfaces for communication between the computer and external devices. This communication is typically bidirectional.
C) transfer information both to and from a hard drive. This option correctly describes the bidirectional nature of a serial port's data transfer capability. A serial port can send data out from the computer (e.g., to write to a device) and receive data into the computer (e.g., to read from a device).
The problem asks for the greatest number that divides 391 and 318, leaving remainders 7 and 6 respectively. This means that if we subtract the remainders from the original numbers, the resulting numbers must be exactly divisible by the required greatest number. Therefore, the greatest number will be the Highest Common Factor (HCF) of these new numbers.
First, subtract the remainder from each given number:
Now, we need to find the HCF (or GCD - Greatest Common Divisor) of 384 and 312. We can use the prime factorization method or the Euclidean algorithm.
Using prime factorization:
To find the HCF, we take the lowest power of the common prime factors:
Alternatively, using the Euclidean algorithm:
\[ 391 - 7 = 384 \\ 318 - 6 = 312 \]Divide 384 by 312:
\[ 384 = 312 \times 1 + 72 \]Divide 312 by 72:
\[ 312 = 72 \times 4 + 24 \]Divide 72 by 24:
\[ 72 = 24 \times 3 + 0 \]The last non-zero remainder is 24, so the HCF is 24.
Correct Option: C) 24
The question asks to identify the statement that is an 'odd one out' regarding safe practices while using ATM and net-banking facilities. This means we need to find the statement that describes an unsafe practice or incorrect advice, while the others describe safe practices.
Correct Option: C) Don't change your PIN at regular intervals.
The question asks to identify the option that best relates to the provided statement. This requires careful reading and understanding of the main message conveyed in the paragraph.
Correct Option: A) True progress in technology involves some risks too.
This option directly reflects the second sentence of the paragraph: "There can be no true progress in technologies without such risks." It accurately captures the essence that risks are an intrinsic part of technological advancement.
The question asks to identify the instrument used for examining a person's digestive tract. We need to evaluate each given option based on its function.
C) Endoscope is the correct answer because an endoscope is specifically designed for direct visual examination of internal organs, including the digestive tract, by inserting a flexible tube with a camera and light source.
The question asks to identify which phenomenon is NOT an example of the refraction of light. We need to understand the definition of refraction and then evaluate each option.
Based on the evaluation, lateral inversion is the only phenomenon not caused by refraction.
Correct Option: C) Lateral inversion is not an example of refraction of light. It is a phenomenon associated with reflection, specifically in plane mirrors, where the left and right sides of an object appear interchanged.
X and Y are parents of four married sons, one married daughter and one unmarried daughter. The married daughter lives with her husband's family; all the others live together in a joint family. Two of the sons have two daughters and one son each. The other two have two sons and one daughter each. How many male members are there in the family?
To find the total number of male members in the family, we need to count all the male individuals mentioned in the problem description who live together in the joint family. We will break down the family structure and count the male members at each level.
C) 11. Based on the step-by-step calculation, the total number of male members in the joint family is 11.