2016

251. Which of the following was/were the reasons for the defeat of British

Which of the following was/were the reasons for the defeat of British during the American War of Independence ?

  • 1. The remoteness of the American Continent and the lack of good roads
  • 2. The British authorities failed to rally the loyalist Americans
  • 3. The Americans benefited from the extraordinary military leadership of George Washington
  • 4. The Americans had access to superior arms and ammunition

[amp_mcq option1=”1, 2 and 4″ option2=”3 only” option3=”2 and 3 only” option4=”1, 2 and 3″ correct=”option4″]

This question was previously asked in
UPSC NDA-2 – 2016
Download PDFAttempt Online
Several factors contributed to the British defeat in the American War of Independence.
Statement 1: The vast distance across the Atlantic and the poor infrastructure in America created significant logistical challenges for transporting troops, supplies, and maintaining communication for the British army. This is a correct reason.
Statement 2: The British failed to effectively mobilize and utilize the support of loyalist Americans, who constituted a significant portion of the population. This lack of broad internal support weakened the British effort. This is a correct reason.
Statement 3: The strategic leadership, perseverance, and ability of George Washington to keep the Continental Army intact and motivated throughout the long war, coupled with key tactical victories, were crucial for the American success. This is a correct reason.
Statement 4: While the Americans eventually received aid from France and other European powers (including arms), they generally did not possess superior arms and ammunition compared to the well-equipped British army throughout the war. They often faced shortages. This statement is incorrect.
Statements 1, 2, and 3 are correct reasons for the British defeat. Option D includes statements 1, 2, and 3.
Factors contributing to American victory included geographical challenges for Britain, British strategic errors, American leadership, foreign aid (especially from France), and strong American motivation.
Other factors included British strategic miscalculations, the costly nature of the war for Britain, and effective diplomacy by American figures like Benjamin Franklin in securing foreign alliances.

252. Which of the following was/were the feature(s) of Lenin’s New Economic

Which of the following was/were the feature(s) of Lenin’s New Economic Policy (NEP) for the Soviet Union ?

  • 1. Private retail trading was strictly forbidden
  • 2. Private enterprise was strictly forbidden

[amp_mcq option1=”1, 2 and 4″ option2=”3 only” option3=”2 and 3 only” option4=”1, 2 and 3″ correct=”option2″]

This question was previously asked in
UPSC NDA-2 – 2016
Download PDFAttempt Online
Lenin’s New Economic Policy (NEP), introduced in 1921, was a temporary move away from strict state control to revive the economy.
Statement 1: “Private retail trading was strictly forbidden”. This was a feature of War Communism (1918-1921), not NEP. NEP *allowed* small-scale private retail trade.
Statement 2: “Private enterprise was strictly forbidden”. This was largely a feature of War Communism. NEP *allowed* small-scale private enterprise.
Statement 3: “State control was maintained over heavy industry and banking”. This is a correct feature of NEP. The state retained control over the “commanding heights” of the economy (heavy industry, banking, foreign trade).
Statement 4: “Peasants were allowed to sell their surplus produce”. This is a correct feature of NEP. The system of forced requisitioning (prodrazvyorstka) from War Communism was replaced by a tax in kind (prodnalog), allowing peasants to sell their surplus on the market.
The correct features among the typical statements are 3 and 4. Looking at the provided options, only option B (“3 only”) consists solely of a correct feature (Statement 3), given that statements 1 and 2 are incorrect features of NEP. Although statement 4 is also a correct feature, it is not offered as “3 and 4 only”, and is included in option A which contains incorrect statements.
NEP allowed limited private trade and enterprise (small scale), replaced grain requisitioning with a tax allowing surplus sales, and maintained state control over major industries and finance.
NEP was a pragmatic policy aimed at increasing agricultural and industrial output by reintroducing market mechanisms. It was successful in reviving the Soviet economy in the 1920s but was eventually phased out under Stalin with the implementation of five-year plans and collectivization.

253. When three resistors, each having resistance r, are connected in paral

When three resistors, each having resistance r, are connected in parallel, their resultant resistance is x. If these three resistances are connected in series, the total resistance will be

[amp_mcq option1=”3x” option2=”3rx” option3=”9x” option4=”3/x” correct=”option3″]

This question was previously asked in
UPSC NDA-2 – 2016
Download PDFAttempt Online
When three resistors, each with resistance $r$, are connected in parallel, their resultant resistance $x$ is given by:
$\frac{1}{x} = \frac{1}{r} + \frac{1}{r} + \frac{1}{r} = \frac{3}{r}$
So, $x = \frac{r}{3}$, which means $r = 3x$.
When these three resistors are connected in series, the total resistance is the sum of individual resistances:
Total resistance $R_{series} = r + r + r = 3r$.
Substituting the expression for $r$ in terms of $x$ ($r=3x$):
$R_{series} = 3 \times (3x) = 9x$.
Resistors in parallel: $\frac{1}{R_{parallel}} = \sum \frac{1}{R_i}$. Resistors in series: $R_{series} = \sum R_i$.
Parallel connections decrease the total resistance, while series connections increase the total resistance. For identical resistors, the parallel resistance is $R/n$ and the series resistance is $nR$, where $R$ is the individual resistance and $n$ is the number of resistors.

254. If the image of an object, formed by a concave mirror is virtual, erec

If the image of an object, formed by a concave mirror is virtual, erect and magnified, then the object is placed

[amp_mcq option1=”at the principal focus” option2=”at the centre of curvature” option3=”beyond the centre of curvature” option4=”between the pole of the mirror and the principal focus” correct=”option4″]

This question was previously asked in
UPSC NDA-2 – 2016
Download PDFAttempt Online
A concave mirror forms a virtual, erect, and magnified image when the object is placed between its pole (P) and principal focus (F). In this position, rays from the object diverge after reflection and appear to originate from a point behind the mirror, forming a virtual image.
Image formation by a concave mirror depends on the object’s position. A virtual, erect, and magnified image is formed when the object is within the focal length (between P and F).
When the object is placed at the principal focus, the image is formed at infinity (real, inverted, highly magnified). When the object is at the centre of curvature, the image is also at the centre of curvature (real, inverted, same size). When the object is beyond the centre of curvature, the image is formed between the principal focus and the centre of curvature (real, inverted, diminished).

255. Which one of the following statements is not correct ?

Which one of the following statements is not correct ?

[amp_mcq option1=”The longest wavelength of light visible to human eye is about 700 nm” option2=”The shortest wavelength of light visible to human eye is about 400 nm” option3=”The wavelength of gamma rays is longer than that of X-rays” option4=”The ability of a telescope to form separable images of close objects is called its resolving power” correct=”option3″]

This question was previously asked in
UPSC NDA-2 – 2016
Download PDFAttempt Online
The electromagnetic spectrum is ordered by wavelength (or frequency/energy). Moving from shorter wavelengths to longer wavelengths, the order is typically Gamma rays, X-rays, Ultraviolet, Visible light, Infrared, Microwaves, Radio waves. Therefore, gamma rays have shorter wavelengths than X-rays. The statement that the wavelength of gamma rays is longer than that of X-rays is incorrect.
Order of electromagnetic spectrum components by increasing wavelength: Gamma < X-ray < UV < Visible < IR < Microwave < Radio.
Statements A and B are correct descriptions of the approximate range of wavelengths for visible light, with red light (around 700 nm) having the longest wavelength and violet light (around 400 nm) having the shortest. Statement D provides a correct definition of resolving power, which is an important characteristic of optical instruments.

256. A particle executes linear simple harmonic motion with amplitude of 2

A particle executes linear simple harmonic motion with amplitude of 2 cm. When the particle is at 1 cm from the mean position, the magnitudes of the velocity and the acceleration are equal. Then its time period (in seconds) is:

[amp_mcq option1=”2π” option2=”2π/√3″ option3=”√3/2π” option4=”2π√3″ correct=”option2″]

This question was previously asked in
UPSC NDA-2 – 2016
Download PDFAttempt Online
For a particle executing simple harmonic motion (SHM) with amplitude $A$ and angular frequency $\omega$, the velocity $v$ at a displacement $x$ from the mean position is given by $v = \pm \omega \sqrt{A^2 – x^2}$, and the acceleration $a$ is given by $a = -\omega^2 x$. The magnitudes are $|v| = \omega \sqrt{A^2 – x^2}$ and $|a| = \omega^2 |x|$. Given $A=2$ cm, and at $x=1$ cm, $|v| = |a|$.
Substituting the values: $\omega \sqrt{2^2 – 1^2} = \omega^2 |1|$
$\omega \sqrt{4 – 1} = \omega^2$
$\omega \sqrt{3} = \omega^2$
Since $\omega$ for SHM is non-zero, we can divide by $\omega$:
$\sqrt{3} = \omega$.
The time period $T$ is related to angular frequency $\omega$ by $T = \frac{2\pi}{\omega}$.
$T = \frac{2\pi}{\sqrt{3}}$.
Formulas for velocity and acceleration in SHM are $|v| = \omega \sqrt{A^2 – x^2}$ and $|a| = \omega^2 |x|$. The time period is $T = 2\pi/\omega$.
The velocity is maximum at the mean position ($x=0$) and zero at the extreme positions ($x=\pm A$). The acceleration is maximum at the extreme positions and zero at the mean position. The relationship between velocity and displacement is elliptical in phase space, while the relationship between acceleration and displacement is linear.

257. Which one of the following statements is not correct?

Which one of the following statements is not correct?

[amp_mcq option1=”Pitch of a sound is its characteristic by which we can generally differentiate between a male voice and a female voice.” option2=”The loudness of sound is related to its frequency.” option3=”A musical sound has certain well-defined frequencies which are generally harmonics of a fundamental frequency.” option4=”The timbre of a particular musical sound is related to the waveform of the sound wave.” correct=”option2″]

This question was previously asked in
UPSC NDA-2 – 2016
Download PDFAttempt Online
The loudness of sound is primarily related to the intensity of the sound wave, which is proportional to the square of its amplitude. Frequency, on the other hand, determines the pitch of the sound. A higher frequency corresponds to a higher pitch, while a larger amplitude corresponds to a louder sound. Therefore, the statement that the loudness of sound is related to its frequency is incorrect.
Loudness relates to amplitude (intensity), while pitch relates to frequency. Timbre relates to waveform (harmonics).
Statement A is correct: Pitch helps differentiate voices; female voices typically have higher fundamental frequencies (and thus higher pitch) than male voices. Statement C is correct: Musical sounds are typically periodic and composed of a fundamental frequency and its harmonic overtones. Statement D is correct: Timbre, or quality, is determined by the combination and relative intensity of overtones present in addition to the fundamental frequency, which shapes the waveform and allows us to distinguish between different instruments or voices.

258. Which one of the following statements is correct?

Which one of the following statements is correct?

[amp_mcq option1=”The speed of sound waves in a medium depends upon the elastic property of the medium but not on inertia property.” option2=”The speed of sound waves in a medium depends upon the inertia property of the medium but not on elastic property.” option3=”The speed of sound waves in a medium depends neither on its elastic property nor on its inertia property.” option4=”The speed of sound waves in a medium depends both on elastic and inertia properties of the medium.” correct=”option4″]

This question was previously asked in
UPSC NDA-2 – 2016
Download PDFAttempt Online
The speed of sound waves in a medium is determined by the medium’s properties related to elasticity and inertia. Sound waves are mechanical waves, meaning they propagate through a medium by causing particles of the medium to oscillate. The elastic property (like Bulk modulus or Young’s modulus) determines how easily the medium restores its shape or volume after being deformed by the wave. The inertia property (density) determines how much resistance the medium offers to changes in motion. The speed of sound increases with increasing elasticity and decreases with increasing density. Therefore, the speed of sound depends on both properties.
Speed of mechanical waves depends on the elastic modulus and density of the medium. Higher elasticity allows faster propagation of disturbances. Higher density provides more inertia, resisting quick motion.
The formula for the speed of sound in a fluid is $v = \sqrt{B/\rho}$, where B is the Bulk modulus and $\rho$ is the density. For a solid rod, $v = \sqrt{Y/\rho}$, where Y is Young’s modulus. These formulas explicitly show dependence on both an elastic property and density.

259. If we plot a graph between volume V and inverse of pressure P (i.e., 1

If we plot a graph between volume V and inverse of pressure P (i.e., 1/P) for an ideal gas at constant temperature T, the curve so obtained is:

[amp_mcq option1=”straight line” option2=”circle” option3=”parabola” option4=”hyperbola” correct=”option1″]

This question was previously asked in
UPSC NDA-2 – 2016
Download PDFAttempt Online
A graph between volume V and inverse of pressure (1/P) for an ideal gas at constant temperature T is a straight line.
According to the Ideal Gas Law, PV = nRT, where P is pressure, V is volume, n is the number of moles, R is the ideal gas constant, and T is temperature. For a fixed amount of gas (n is constant) at a constant temperature (T is constant), the product nRT is a constant. Let’s call this constant C. So, PV = C (This is Boyle’s Law). We want to plot V against 1/P. Rearranging the equation, we get V = C * (1/P). If we let Y = V and X = 1/P, the equation becomes Y = CX. This is the equation of a straight line passing through the origin with slope C (which is equal to nRT).
Plotting V versus P directly would yield a hyperbola (PV = C). A parabola is typically associated with quadratic relationships, and a circle with relationships involving the sum of squares.

260. Which one of the following four particles, whose displacement x and ac

Which one of the following four particles, whose displacement x and acceleration a, are related as follows, is executing simple harmonic motion?

[amp_mcq option1=”a = +3x” option2=”a = +3x²” option3=”a = -3″ option4=”a = -3x” correct=”option4″]

This question was previously asked in
UPSC NDA-2 – 2016
Download PDFAttempt Online
The particle executing simple harmonic motion is the one where acceleration ‘a’ and displacement ‘x’ are related as a = -3x.
Simple Harmonic Motion (SHM) is defined by a linear restoring force proportional to the displacement from the equilibrium position and directed towards it. According to Newton’s second law (F = ma), this implies that the acceleration is also proportional to the displacement and directed towards the equilibrium position. The general form of the acceleration-displacement relationship for SHM is a = -ω²x, where ω² is a positive constant (related to the system’s properties like mass and stiffness). Option D, a = -3x, fits this form with ω² = 3 (or ω = √3).
Option A, a = +3x, represents unstable equilibrium where the acceleration is away from the origin. Option B, a = +3x², is a non-linear relationship. Option C, a = -3, represents motion under constant acceleration, which is not SHM.
Page 1Page 2Page 3Page 4Page 5