Explore topic-wise InterviewSolutions in Current Affairs.

(b) It is helpful in achieving an economical use of water and a higher yield of grain

Punjab State in India is known as the 'Granary of India.

(c) Different crops are grown in succession to maintain the soil fertility

The Milky Way Galaxy was first observed by Galileo.

Soyabeans are rich in Proteins.

Rice is a tropical monsoon crop.

Characteristics of entropy:

• Entropy is a thermodynamic state function that is a measure of the randomness or disorderliness of the system. 
• In general, the entropy of gaseous system is greater than liquids and greater than solids. The symbol of entropy is S. 
• Entropy is defined as “for a reversible change taking place at a constant temperature (T), the change in entropy (∆S) of the system is equal to heat energy absorbed or evolved (q) by the system divided by the constant temperature (T). 

\(ΔS_{sys}\) = \(\frac{q_{rev}}{T}\)

• If heat is absorbed, then ∆S is positive and there will be increase in entropy. If heat is evolved, ∆S is negative and there is a decrease in entropy
• The change in entropy of a process represented by ∆S and is given by the equation,

\(ΔS_{sys}\) =S_f - S_i

• If S_f > S_i , ∆S is positive, the reaction is spontaneous and reversible. 
• If S_f < S_i , ∆S is negative, the reaction is nonspontaneous and irreversible. 
• Unit of entropy: SI unit of entropy is J K^-1

Correct answer is 101.00

Unnilunium ⇒ 101

1. Magnesium oxide has very strong ionic bonds as compared to magnesium fluoride. 

2. Mg²⁺ and O^2- have charges of +2 and -2, respectively. 

3. Oxygen ion is smaller than fluoride ion. 

4. The smaller the ionic radii, the smaller the bond length in MgO and the bond is stronger than MgF₂ .

5. Due to more strong bond nature in MgO, it has high melting point than MgF₂

(C) (B) and (C) only

Correct option is (C) 20 kHz

Bandwidth = 2 f_m

= 2 x 10⁴ Hz = 20 x 10³ Hz

= 20 KHz

2x + 3y → 41 + m 

1. 2x reacts with 3y to give products. 

8x reacts with 15y means, y is the excess because 8 moles of x should react with 4 × 3y = 12y moles of y to give products. 

In this reaction 15y moles are used. 

Therefore, 3 moles of y is excess and x is the limiting agent.

2. When 8 moles of x react with 12 moles of y, the product formed will be 4 × 41 i.e. 161 and 4m as product. 

8x+ 12y → 161 + 4m

3. At the end of the reaction, the excess reactant left is 3 moles of y.

Avogadro number is the number of atoms present in one mole of an element or number of molecules present in one mole of a compound. The value of Avogadro number (N) = 6.023 x 10²³

Lassagine’s extract preparation:

1. A small piece of Na dried by pressing between the folds of filter paper is taken in a fusion tube and it is gently heated. When it melts to a shining globule, a pinch of organic compound is added. 

2. The tube is heated till reaction ceases and become red hot. Then it is plunged in 50 ml of distilled water taken in a china dish and the bottom of the tube is broken by striking it against the dish. 

3. The contents of the dist is boiled for 10 minutes and then it is filtered. The filtrate is known as Lassaigne’s extract.

1. Octahedral geometry is possible by sp³ d² (or) d² sp³ hybridisation. 

2. Tetrahedral geometry is possible by sp³ hybridisation. 

3. Square planar geometry is possible by dsp² hybridisation.

No, It is not correct. The accurate and absolute definition is as follows: 

Ionization energy is defined as the minimum amount of energy required to remove the most loosely bound electron from the valence shell of the isolated neutral gaseous atom in its ground state.

(b) Increased potential energy

1. In the preparation of mortar, a building material. 

2. In white wash due to its disinfectant nature. 

3. In glass making and tanning industry. 

4. For the preparation of bleaching powder and for the purification of sugar.

When a gas dissolves in a liquid under a given pressure, there will be an equilibrium between gas molecules in the gaseous state and those dissolved in the liquid. 

Example: In carbonate beverages the following equilibrium exists.

CO₂ (g) ⇄ CO₂ (solution).

(d) The axis of rotation

Refers to the below link

http://bit.ly/2Ta4eX9

Manganese(atomic number 25) is just above the Technetium(atomic number 43).

Thus configuration of Manganese (Atm. Number 25) is = 1s² 2s² 2p⁶ 3s² 3p⁶ 4s^{​​​​​2} 3d⁵ 

^{Because of high energy in 3d so e- First enters in 4s according to [n+1] rule.}

Correct Answer is: (c) E

The flux linked with the coil does not depend upon the position of the axis of rotation. The induced emf depends only on the rate of change of this flux. 

Correct Answer is: (a) 5 cm

f = 100 cm/16 = 6.25 cm

Maximum magnification is obtained when the image is formed at D = 25 cm.

Thus, v = -25 cm.

1/v - 1/u = 1/f gives u = - 5 cm.

Correct Answer is: (b) forced

When sound is incident on a receiver, it vibrates at the frequency of the incident sound. This is forced vibration.

By conservation of linear momentum m₁v₁ = m₂v₂

\(\cfrac{m_1}{m_2}\) = \(\cfrac{v_2}{v_1}\)

m = p.v

\(\cfrac{p.v_1}{p.v_2}\) = \(\cfrac23\)

\(\cfrac{\cfrac43\pi r_1^3}{\cfrac43\pi r_2^3}\) = \(\cfrac23\)

\(\left(\cfrac{r_1}{r_2}\right)^3\) = \(\left(\cfrac23\right)\)

\(\cfrac{r_1}{r_2}\) = \(\left(\cfrac23\right)^{1/3}\)

Pin = 11*10³ kcal/kg * 5 kg/hr

Pin = 55*10³ kcal/hr

unit conversion:

1 kcal/hr = 0.001163 kW

Pin = 55*10³ kcal/hr * 0.001163 kW /kcal/hr

Pin = 63.965 kW

Power Out:

Pout = 20 kW

Efficiency:

Eff = Pout / Pin

Eff = 20 kW / 63.965 kW

Eff = 0.3127 or 31.27%

The nuclear force is nearly independent of whether the nucleons are neutrons or protons. This property is called charge independence. The force depends on whether the spins of the nucleons are parallel or antiparallel, as it has a non-central or tensor component.

i)  It has two shells, and both of which are completely filled with electrons. It means. n = 2 (n = number of shell)

∴ Electronic configuration of element will be 1s² 2s² 2p⁶

it is the electronic configuration of "Ne"(Ƶ = 10) 'Neon'

ii) We have given, electronic configuration 2, 8, 3. It means number of shell in element are = 3

and total number of electrons are = 13

Therefor electronic configuration will be 1s² 2s² 2p⁶ 3s² 3p¹

Ƶ = 10

The above electronic configuration correspond to the Aluminium element (Al)

iii) There are total three shells, it means n = 3and valence shell has five electron. Therefore the electronic configuration will be

1s² 2s² 2p⁶ 3s² 3p³

it is the electronic configuration of phosphorous element.

iv) There are total four shells, it means, n = 4₁ and valence shell has two electrons. Therefore the electronic configuration will be

1s² 2s² 2p⁶ 3s² 3p⁶ 4s²

It is the electronic configuration of calcium (Ca) element

v) There are twice electrons in the second shell as in the first shell.

We know that, first shell accommodate only two electrons. Therefore four electrons are present in second shell. The electronic configuration of element will be

1s² 2s² 2p²

It is the electronic configuration of carbon (C) element

\((\frac{1}{2})^4(\frac{1}{2})^3=(\frac{1}{2})^7\)

The experiment is rainfall in a week.

The event that it will rain is success and the event that it will not rain is failure.

Therefore, the probability of getting success is p = 50% = \(\frac{1}{2}\)

The probability of getting failure is q = 1-p = \(\frac{1}{2}\)

Rainfall in a week is binomial distribution whose parameters are n = 7 and p = \(\frac{1}{2}\)

Now, the probability that it rains only on first 4 days of the week = ⁷C₄ p⁴ q³

= \(\frac{7\times6\times5}{3!}\)\(\big(\frac{1}{2}\big)^4\big(\frac{1}{2}\big)^3\) = \(\frac{7\times6\times5}{3\times2}\big(\frac{1}{2}\big)^7\)= 35\(\big(\frac{1}{2}\big)^7\)= 35 x \(\frac{1}{128}\) = \(\frac{35}{128}\)

Log₂₅10 = \(\frac {1}{log_{10}25} = \frac {1}{log_{10}5^2} = \frac {1}{2log_{10}5}\)

= \(\frac {log_510}{2}\) (∵ log_ab = \(\frac {1}{log_ba}\))

Hence proved

It is the geometric arrangement of a computer system in network. Common topologies include a Linear bus, star, ring, and ring.

Order = 2 

Degree = 1 

Sum = 3

Each column in a table is identified by a distinct header is called a field.

The fixed size of memory allocation and cannot be altered during runtime is called static memory allocation.

A serial port is able to transmit a single stream of data at a time. A parallel port is able to transmit multiple data streams at a time. A serial port sends data bit by bit after sending a bit at a time. A parallel port sends data by sending multiple bits in parallel fashion.

C operators can be classified into the following types:

Arithmetic operators

Relational operators

Logical operators

Bitwise operators

Assignment operators

Conditional operators

Special operators

Universal gate is a gate using which ail the basic gates can be designed. NAND and NOR are universal gates.

Private access means a member data can only be accessed by the member function of that class only.

\(A = \begin{bmatrix}2&1\\2&1\end{bmatrix} ; B = \begin{bmatrix}9&3\\3&1\end{bmatrix}\)

(i) \(AX = A\)

Let \(X = \begin{bmatrix}a&b\\c&d\end{bmatrix}\)

\(\begin{bmatrix}2&1\\2&1\end{bmatrix} \begin{bmatrix}a&b\\c&d\end{bmatrix}= \begin{bmatrix}2&1\\2&1\end{bmatrix} \)

⇒ \(\begin{bmatrix}2a +c&2b + d\\2a +c&2b+d\end{bmatrix} = \begin{bmatrix}2&1\\2&1\end{bmatrix} \)

\(\therefore 2a + c = 2\) ⇒ \(c = 2 - 2a = 2(1 - a) ; a\in R\)

\(\therefore 2b + d = 1\) ⇒ \(d = 1 - 2b; b \in R\)

So, there is infinite many such matrices X exist for which AX = A as |A| = 0.

X is of the type \(\begin{bmatrix}a&b\\2(1 -a)&1-2b\end{bmatrix}\).

(ii) \(XA = I\)

\(\begin{bmatrix}a&b\\c&d\end{bmatrix} \begin{bmatrix}2&1\\2&1\end{bmatrix} = \begin{bmatrix}1&0\\0&1\end{bmatrix} \)

\(\begin{bmatrix}2(a +b)&a + b\\2(c + d)&c+d\end{bmatrix} = \begin{bmatrix}1&0\\0&1\end{bmatrix} \)

\(\therefore 2(a +b) = 1\) ⇒ \(a + b = \frac 12 \)    (By comparing a₁₁ elements of both matrices)

and \(a +b = 0\)    (By comparing a₁₂ elements of both matrices)

(Not possible at same time)

Hence, no such matrix X exists for Which XA = I.

(iii) \(XB = 0 \) but \(BX \ne 0\)

\(\begin{bmatrix}a&b\\c&d\end{bmatrix} \begin{bmatrix}9&3\\3&1\end{bmatrix} = \begin{bmatrix}0&0\\0&0\end{bmatrix} \)

⇒ \(\begin{bmatrix}3(3a +b)&3a + b\\3(3c + d)&3c+d\end{bmatrix} = \begin{bmatrix}0&0\\0&0\end{bmatrix} \)

⇒ \(3a + b = 0\) and \(3c + d = 0\)

⇒ \(b = -3a \) and \(d= -3c; a,c \in R\) 

But \(BX \ne 0\)

\(\begin{bmatrix}9&3\\3&1\end{bmatrix}\begin{bmatrix}a&b\\c&d\end{bmatrix} \ne \begin{bmatrix}0&0\\0&0\end{bmatrix} \)

⇒ \(\begin{bmatrix}3(3a +c)&3(3b + d)\\3a+c&3b+d\end{bmatrix} \ne\begin{bmatrix}0&0\\0&0\end{bmatrix} \)

⇒ \(3a + c \ne 0\)

& \(3b +d \ne 0\)

⇒ \(3b - 3 c \ne 0\)

⇒ \(b - c \ne 0\)

⇒ \(b \ne c\)

⇒ \(-3a \ne c\)

Hence, \(X = \begin{bmatrix}a&b\\c&d\end{bmatrix} = \begin{bmatrix}a&-3a\\c&-3c\end{bmatrix} ; c\ne -3a\)

Hence, there is infinite many such X matrices exist for which \(XB = 0\) but \(BX \ne 0\) and of the type \(X =\begin{bmatrix}a&-3a\\c&-3c\end{bmatrix} ; c\ne -3a\).

The given system has a set of non zero integral solution and system is homogeneous system.

\(\therefore \begin{vmatrix}2&3&-1\\3&2&k\\4&1&1 \end{vmatrix} \ne 0\)

⇒ \(2(2 - k) - 3(3 - 4k) -1(3 - 8) \ne 0\)

⇒ \(4 - 2k -9 + 12k + 5 \ne 0 \)

⇒ \(10k \ne 0\)

⇒ \(k\ne 0\)

System has integral solution, so k must have integral values.

Hence, least positive value of z is 1.