Explore topic-wise InterviewSolutions in Current Affairs.

This section includes 7 InterviewSolutions, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.

1.

In two different societies, there are some school going students including girls as well as boys. Satish forms two sets with these students for his college project.Let = {a1, a2, a3, a4, a5 } and B= {b1, b2, b3, b4 } where ai's and bi's are school going students of first and second societies respectively.Satish decides to explore these sets for various types of relations and functions.With the help of above information answer the following question:Satish and his friend Rajat are interested to know the number of symmetric relations defined on both the sets and , separately. Satish decides to find the symmetric relation on set , while Rajat decides to find the symmetric relations on set . What is the difference between their results ?

Answer»

We know that total number of symmetric relation on set having n elements is

\(2^{\cfrac{n(n+1)}2}\).

Given = {a1, a2, a3, a4, a5 } and B = {b1, b2, b3, b4 }.

Therefore, A has 5 elements and B has 4 elements.

Therefore, total number of symmetric relation on set A is  \(2^\cfrac{5(5+1)}2\) = 215 .

And total number of symmetric relation on set B is \(2^\cfrac{4(4+1)}2\) = 210.

Difference between their results is 215 − 210 = 210(25 − 1) = 210(32 − 1) 

= 31 × 1024 = 31774.

2.

Find the value of k for which the quadratic equation 2x2 + kx + 2 = 0 has equal root. or

Answer»

Given that quadratic equation 2x2 + kx + 2 = 0 has equal roots.

By comparing given quadratic equation with standard quadratic equation ax2 + bx + c, we get a = 2, b = k and c = 2.

We know that the quadratic equation ax2 + bx + c has equal roots, if b2 - 4ac = 0.

Therefore, k2 − 4 × 2 × 2 = 0 ⇒ k2 = 16 = 42 ⇒ k = ±4.

Hence, for k = ±4, the quadratic equation 2x2 + kx + 2 = 0 have equal roots.

3.

Analysis about Resistive Network ?

Answer»

1. Circuit: A circuit is a closed conducting path through which an electric current either flows or intended to flow. A circuit consists of active and passive elements in it.

2. Linear Circuit: A circuit whose parameters are constant with time and they don’t change with voltage or current and they obeys Ohm’s law.

3. Non-linear Circuit: It is that circuit whose parameters change with voltage or current.

4. Bilateral Circuit: A bilateral circuit is one whose properties are the same in either direction. Example, a transmission line & parameter such as resistor, inductor & capacitor.

5. Unilateral Circuit: It is a circuit whose properties change with the direction of its operation. Example such as diode, triode , transistor & SCR.

6. Active Network: is a network which contains one or more than one source of emf along with passive element.

7. Passive Network: is one which contains no source of emf.

8. Node: is a point in a circuit where two or more circuit elements are connected together.

9. Branch: is the part of a network which lies between two nodes.

10.Loop: It is a close path in a circuit in which no element or node is encountered more than once.

11.Mesh: It is a loop that contains no other loop within it.

It should be noted that, unless stated otherwise, an electric network would be assumed passive.

There are two general approaches to network analysis:

i. Direct Method

ii. Network Reduction Method

Direct Method: Here the network is left in its original form while determining its voltages and currents.

e.g.: Loop Analysis, Nodal Analysis, Superposition Theorem, Compensation Theorem, and Reciprocity Theorem.

Network Reduction Method: Here, the original network is converted into a much simpler equivalent circuit for rapid and easy calculation.

e.g.: Delta/Star and Star/delta Conversions, Thevenin’s Theorem and Norton’s Theorem.

4.

The only correct combination is :A. (I)(iii)(R)B. (II)(i)(S)C. (III)(ii)(P)D. (IV)(iv)(Q)

Answer» Correct Answer - A
(I)First line of Balmer series
`n_1=2 " " n_2=3`
`DeltaP.E=27.2xx(Z)^2[1/n_1^2-1/n_2^2]`
=`27.2xx(1)^2[1/4-1/9]=27.2xx5/36=3.78 ev`
`DeltaE=13.6xx(1)^2[1/4-1/9]=1.88 ev`
`barv=Rxx(1)^2[1/4-1/9]=(5R)/(36)`
`lambda=36/(5R)`
Angular momentum=`(3h)/(2pi)-(2h)/(2pi)=(h)/(2pi)`
(II)Third line of paschen series of `He^+` ion
`n_1=3 " " n_2=6`
`DeltaP.E=27.2xx(2)^2[1/9-1/36]=9.06 ev`

`DeltaE=13.6xx(2)^2[1/9-1/36]=4.54 ev`
`barv=Rxx(2)^2[1/9-1/36]=R/3`
`lambda=3/(R)`
Angular momentum=`(6h)/(2pi)-(3h)/(2pi)=(3h)/(2pi)`
(III)Lyman series limit for `Li^(+2)` ion
`n_1=1 " " n_2=oo`
`DeltaP.E=27.2xx(3)^2[1/1^2-1/oo^2]=27.2xx9=244.8 ev`

`DeltaE=13.6xx(9)[1/1^2-1/oo^2]=122.4 ev`
`barv=Rxx(3)[1/1^2-1/oo^2]=9R`
(IV)`2^(nd)` line of Lyman series for `He^+` ion
`n_1=1 " " n_2=3`
`DeltaP.E=27.2xx(2)^2[1/1-1/9]=96.71 ev`

`DeltaE=13.6xx(2)^2[1/1-1/9]=48.4 ev`
`barv=Rxx(2)^2[1/1-1/9]=(32R)/9,lambda=9/(32R)`
Angular momentum=`(3h)/(2pi)-(h)/(2pi)=(2h)/(2pi)=h/pi`
5.

The only correct combination is :A. (I)(ii)(P)B. (IV)(iii)(Q)C. (II)(iv)(R)D. (III)(i)(S)

Answer» Correct Answer - D
(I)First line of Balmer series
`n_1=2 " " n_2=3`
`DeltaP.E=27.2xx(Z)^2[1/n_1^2-1/n_2^2]`
=`27.2xx(1)^2[1/4-1/9]=27.2xx5/36=3.78 ev`
`DeltaE=13.6xx(1)^2[1/4-1/9]=1.88 ev`
`barv=Rxx(1)^2[1/4-1/9]=(5R)/(36)`
`lambda=36/(5R)`
Angular momentum=`(3h)/(2pi)-(2h)/(2pi)=(h)/(2pi)`
(II)Third line of paschen series of `He^+` ion
`n_1=3 " " n_2=6`
`DeltaP.E=27.2xx(2)^2[1/9-1/36]=9.06 ev`

`DeltaE=13.6xx(2)^2[1/9-1/36]=4.54 ev`
`barv=Rxx(2)^2[1/9-1/36]=R/3`
`lambda=3/(R)`
Angular momentum=`(6h)/(2pi)-(3h)/(2pi)=(3h)/(2pi)`
(III)Lyman series limit for `Li^(+2)` ion
`n_1=1 " " n_2=oo`
`DeltaP.E=27.2xx(3)^2[1/1^2-1/oo^2]=27.2xx9=244.8 ev`

`DeltaE=13.6xx(9)[1/1^2-1/oo^2]=122.4 ev`
`barv=Rxx(3)[1/1^2-1/oo^2]=9R`
(IV)`2^(nd)` line of Lyman series for `He^+` ion
`n_1=1 " " n_2=3`
`DeltaP.E=27.2xx(2)^2[1/1-1/9]=96.71 ev`

`DeltaE=13.6xx(2)^2[1/1-1/9]=48.4 ev`
`barv=Rxx(2)^2[1/1-1/9]=(32R)/9,lambda=9/(32R)`
Angular momentum=`(3h)/(2pi)-(h)/(2pi)=(2h)/(2pi)=h/pi`
6.

By passing a certain amount of charge through `NaCl` solution, `9.2` lit of `Cl_(2)` were liberated at STP. When the same charge is passed through a nitrate solution of metal `M` i.e. `M(NO_(3))x 7.467` gm of the metal was deposited . If the specific heat of metal is `0.16cal//gm`, what is the value of `x` (`x` is integer).

Answer» Correct Answer - 4
Specific heat `xx` At.Wt. `=6.4`
Atomic weight `=29.63`
Eq. of metal `=` Eq. of `Cl_(2)`
`(7.467xx x)/29.63=(71xx9.2)/(22.4xx35.5)`
`x=3.25`
`x=3` (`x` is an integer)
7.

A chemist has one mole of X-atoms.He finds that on absorption of 4.10 kJ, half of X-atoms transfer one electron to the other half.It all the resulting X ions are subsequently converted to `X^+` ions, an addition of 735 kJ is required.Find the electron affinity of X.

Answer» Correct Answer - 325
`X/2toX^(+)/2+e " " 1/2I.E.`…(i)
`e+X/2toX^(-)/2 " " 1/2 E.A. (-ve)`….(ii)
(i)+(ii)
`Xto1/2X^(+)+1/2X^(-) " " 1/2(I.E.-E.A.)=410 kJ`
I.E.-E.A.=820 kJ
Now `1/2X^(-)to1/2X^(+)+2e^(-)`….(iii) `DeltaH=735`
Now equation (ii) can be achieved by (i)+reverse (ii) and we will get
`1/2I.E.+1/2E.A.=735`
`I.E.+E.A.=1470`...(iv)
2E.A.=650
E.A.=325 kJ/mol.
8.

Suggest a suitable method to separate sugar and salt from an aqueous solution containing them.

Answer»

Fractional crystallization is a suitable method to separate sugar and salt from an aqueous solution containing them due to differences in their solubilities in water.

9.

Give the reasons for the deviation of real gases from ideal behaviour?

Answer»

1. There is no intermolecular force of attraction within gaseous molecules (at high pressure and low temperature there is appreciable intermolecular force of attraction). 

2. The actual volume of the molecule is negligible as compared to total volume of the gas. (At high pressure the gaseous molecule occupy minimum volume, which is not negligible).

10.

Distinguish between Sigma and Pi bonds.

Answer»
Sigma (σ) BondPi (π) Bond
1. The bond is formed by the axial overlap of the atomic orbitals.1. The bond is formed by the sidewise overlap of the atomic orbitals.
2. s-orbitals can take part in the sigma bond formation2. s-orbitals do not take part in the pi-bond formation.
11.

Trans-2 Butene has higher melting point than cis-2-butene, why?

Answer»

Because more close packing of molecules is possible in trans-isomer due to more symmetry.

12.

Name the quantum number that specifies (i) Size of an orbital (ii) Shape of an orbital.

Answer»

(i) Principal quantum number specifies size of an orbital 

(ii) Azimuthal quantum number specifies shape of an orbital.

13.

Statement 1: Two spheres undergo a perfectly elastic collision. The kinetic energy of system of both spheres is always constant. [There is no external force on system of both spheres]. Statement 2: If net external force on a system is zero, the velocity of centre of mass remains constant.A. Statement `-1` is True, Statement `-2` is True, Statement`-2` is a correct explanation for Statement`-1`B. Statement `-1` is True,Statement`-2` is True, Statement`-2` is NOT a correct explanation for Statement`-1`C. Statement `-1` is True, Statement `-2` is FalseD. Statement `-1` is False, Statement `-2` is True.

Answer» Correct Answer - D
During collision `KE` of system is not constant , hence statement `-1 ` is false.
14.

A heavy body of mass `25kg` is to be dragged along a horizontal plane (`mu` = `(1)/(sqrt(3))`. The least force required is `(1 kgf = 9.8 N)`A. 25 kgfB. 2.5 kgfC. i 2.5 kgfD. 50 kgf

Answer» Correct Answer - C
`F_("min") = (mu mg)/(sqrt(1 + mu^(2)))`
15.

What is the max data transfer rate for optical fiber cable?(a) 10 Mbps(b) 100 Mbps(c) 1000 Mbps(d) 10000 Mbps

Answer» Correct option is (d) 10000 Mbps

For explanation: Fiber channel speeds have been increasing over the years. 10000 Mbps is the max data transfer rate for optical fiber cables. It is said to be the fastest among the other kinds of cables like STP cables and co-axial cables. People are now using optical fiber cables instead of STP cables for LANs due to their fast data transfer capability.
16.

A uniform plane electromagnetic wave incident normally on a plane surface of a dielectric material is reflected with a VSWR of 3. What is the percentage of incident power that is reflected (a) 10% (b) 25% (c) 50% (d) 75%

Answer»

(b) 25% 

VSWR = \(\frac{1+|r|}{1-|r|}\)

3 = \(\frac{1+|r|}{1-|r|}\)

r = 0.5

\(\frac{p_r}{p_i}\) = r2 = (0.5)2

= 0.25

25% of incident power is reflected.

17.

Diagonal relationship is down byA. All elements with their diagonally opposite elements.B. All elements of `3rd` and `4th` periodsC. Some of the elements of `2nd` and `3rd` periodsD. Elements of d-block

Answer» Correct Answer - C
18.

How many number of pairs of elements exhibit diagonal relationship.

Answer» Correct Answer - 3
19.

The tendency for blood flow to be turbulent increases when there is a decrease in blood A. Vessel diameter. B. Density. C. Flow velocity. D. Viscosity. E. Haemoglobin level.

Answer»

A. False The tendency is directly proportional to vessel diameter. 

B. False The tendency is directly proportional to fluid density. 

C. False The tendency is directly proportional to velocity. 

D. True The tendency is inversely proportional to viscosity. 

E. True In anaemia, the increase in velocity and decrease in viscosity of blood in the hyperdynamic circulation promote turbulence; bruits may be heard over peripheral arteries.

20.

The correct order of nucleophilicity is(A) F- > OH- (D) \(NH_2^->NH_3\)

Answer»

Correct option is (D) \(NH_2^- > NH_3 \)

Nucleophilicity \(\propto\) electro density on donor atom

Nucleophilicity \(\propto\) size of donor atom (in gas)

Nucleophilicity \(\propto\) 1/EN of atom (for period) 

21.

Fungus prefers to grow in :- (1) Warm and humid places (2) Cold and humid places (3) Warm and cold both (4) Warm, cold and humid places

Answer»

Correct option is (1) Warm and humid places

22.

Where can one find the tree which Cruelty plants? (The Human Abstract)a. In the cruelest of placesb. In the warzonesc. In the human braind. In the peaceful places

Answer»

Correct answer is (c) In the human brain

23.

There is unemployment in the country. The government launches employment guarantee schemes. Explain the effect of this action of the government using the production possibilities curve.

Answer» Economic value is reflected in terms of increased output and income as economy would move to a point on the PPC.
24.

Economics is the study of:A. How society manages its unlimited resourcesB. How to reduce our wants until we are satisfiedC. How society manages its scarce resourcesD. How to fully satisfy our limited wants

Answer» Correct Answer - C
C. How society manages its scarce resources
25.

People of a country are becoming more and aware of the importance of education. Explain its effect on the production potential of the country using the production possibilities frontier.

Answer» Economic value is reflected in terms of increased output and income as economy would move to a point on the PPC.
26.

Define frequency polygon

Answer»

A frequency polygon is a graph constructed by using lines to join the midpoints of each interval, or bin. The heights of the points represent the frequencies. A frequency polygon can be created from the histogram or by calculating the midpoints of the bins from the frequency distribution table.

27.

Consider the following table `{:("Production Possibilities",A,B,C,D,E),("Guns (Units)",0,1,2,3,4),("Butter(Units)",10,9,7,4,0):}` If the above points A to E are depicated on a graph, then such PPF would be:A. Convex to the originB. Concave to the originC. Straight lineD. Rectangular hyperboal

Answer» Correct Answer - B
B.
28.

Increased sympathetic drive to the heart increases the A. Rate of diastolic depolarization in sinuatrial node cells. B. Coronary blood flow. C. Rate of conduction in Purkinje tissue. D. Slope of the Frank–Starling (work versus stretch) curve of the heart. E. Ejection fraction of the left ventricle.

Answer»

A. True This increases the rate of impulse generation and hence heart rate. 

B. True The increase in myocardial metabolism generates vasodilator metabolites. 

C. True Rapid spread of excitation in the ventricles results in more forceful contractions as the ventricular fibres are activated nearly simultaneously. 

D. True This enhances the force of contraction at any given filling pressure. 

E. True Due to the increased force of contraction.

29.

The strength of contraction of left ventricular muscle increases when A. End-diastolic ventricular filling pressure rises. B. Serum potassium levels rise. C. Blood calcium levels fall.D. Strenuous exercise is undertaken. E. Peripheral resistance is increased as in hypertension.

Answer»

A. True As seen in the Frank–Starling left ventricular function curve. 

B. False High K+ levels decrease cardiac contractility. 

C. False Calcium channel blockers decrease cardiac contractility. 

D. True Due to increased sympathetic drive to the ventricles and increased venous return. 

E. True Initially by increased ventricular filling: later by ventricular hypertrophy.

30.

The country lacks capital needed to raise national income of the country. Government initiates policies favouring globalisation to attaract foreign capital. Explain the effect of these policies using production possibilities curve

Answer» Economic value is reflected in terms of increased output and income as economy would move to a point on the PPC.
31.

What do you mean by opportunity cost?Explain with the help of a numerical example.

Answer»

An opportunity cost is the cost of an alternative that must be forgone in order to pursue a certain action. In other words, the cost of enjoying more of one good in terms of sacrificing the benefit of another good is termed as opportunity cost of the additional unit of the good.

Example: We have Rs 15,000 with two choices a) to invest in the shares of a company XYZ or b) to make a fixed deposit which gives interest 9%. If the company XYZ gives a return of 15%, we will benefit when we invest in the shares as the alternative would be less profitable. However if company’s return is only 3% when we could have made a return of 9% from FD, then our opportunity cost is (9% - 3% = 6%).

32.

The velocity of blood flow A. In capillaries is low because they offer high resistance to flow. B. In veins is greater than in venules. C. Can fall to zero in the ascending aorta during diastole. D. Is greater towards the centre of large blood vessels than at the periphery. E. In the circulation falls as the haematocrit falls.

Answer»

A. False It is low because the capillary bed has a large total cross-sectional area. 

B. True The venous bed has a smaller total cross-sectional area than the venular bed. 

C. True There is a brief period of retrograde flow as the aortic valve closes. 

D. True Axial flow occurs in large vessels; near the walls, flow velocity is zero. 

E. False It rises due to the compensatory increase in cardiac output.

33.

The net loss of fluid from capillaries in the legs is increased by A. Arteriolar dilation. B. Change from the recumbent to the standing position. C. Lymphatic obstruction. D. Leg exercise. E. Plasma albumin depletion.

Answer»

A. True This increases capillary hydrostatic pressure. 

B. True In the standing position, capillary pressure increases by the hydrostatic equivalent of the column of blood below the heart. 

C. False Lymphatic obstruction allows tissue fluid to accumulate; the rise in interstitial pressure reduces the capillary transmural hydrostatic pressure gradient. 

D. True Capillary pressure rises during the exercise hyperaemia. 

E. True Hypoproteinaemia decreases the transmural colloid osmotic pressure gradient.

34.

In the estimation of cardiac output using the Fick principle A. Pulmonary blood flow is measured. B. The PO2 of arterial and mixed venous blood are measured. C. Oxygen uptake is estimated from alveolar PO2 measurements. D. Pulmonary arterial blood is sampled to measure the oxygen in mixed venous blood. E. Pulmonary venous blood is sampled to measure the oxygen in arterial blood.

Answer»

A. True Pulmonary blood flo = right ventricular output = cardiac output. 

B. False The O2 content of arterial and mixed venous blood are measured. 

C. False To measure O2 consumption, the subject breathes from a spirometer filled with oxygen with a CO2 absorber in the circuit; an open circuit method may also be used. 

D. True The pulmonary artery is relatively easy to catheterize and the venous blood it contains is thoroughly mixed. 

E. False Pulmonary veins are difficult to catheterize. Blood from any artery may be used since the O2 content of peripheral arterial blood is the same as that in the pulmonary vein.

35.

What is likely to be the impact of "Make in India" appeal to the foreign investors by the Prime Minister of India, on PPF of India ? Explain.

Answer» When investments increases by the campaign which was started by our prime minister named as make in India campaign, it will make PPC shift rightward as production will increase.The right shift indicates our economic growth. The right, the shift, the better, the economy. Well, since the country has increased resources, which is surely going to boost our economy.The PPC will shift right.
36.

Explain the effect of upgradation of technologies on the production potential of the country. Use diagrame.

Answer» Economic value is reflected in terms of increased output and income as economy would move to a point on the PPC.
37.

Severe systemic hypertension may result in A. An increase in the number of myocardial cells in the left ventricle. B. Increased QRS voltage in certain leads. C. Increased coronary blood flow. D. Pulmonary oedema. E. Impaired vision.

Answer»

A. False The cells increase in size (hypertrophy), not in number (hyperplasia). 

B. True Due to the left ventricular hypertrophy. 

C. True Due to increased left ventricular work. 

D. True Due to left ventricular failure. 

E. True Due to damage to retinal blood vessels.

38.

During isometric ventricular contraction A. The entry and exit valves of the ventricle are closed. B. Pressure in the aorta rises. C. Pressure in the atria falls. D. Left coronary blood flow falls. E. The rate of rise in pressure is greater in the right than in the left ventricle.

Answer»

A. True Hence no blood leaves the ventricles. 

B. False Pressure in the aorta falls as run-off of blood to the tissues continues. 

C. False It rises as ventricular pressure causes the AV valves to bulge into the atria. 

D. True The blood vessels are squeezed by the contracting myocardium. 

E. False The greater force of contraction in the left ventricle gives a greater rate of rise of pressure.

39.

Cardiac output A. Is normally expressed as the output of one ventricle in litres/minute.B. May not increase when heart rate rises. C. Usually rises when a person lies down. D. Rises in a hot environment. E. Does not increase in exercise following denervation of the heart.

Answer»

A. True The output from the left and right ventricle is the same. 

B. True It depends on what happens to stroke volume. 

C. True Lying down normally increases the filling pressure of the heart. 

D. True To meet the needs of increased metabolism and increased skin blood flow. 

E. False The output does increase due to changes in the filling pressure, level of circulating hormones, etc.

40.

The second heart sound differs from the first heart sound in that it is A. Related to turbulence set up by valve closure. B. Longer lasting than the first sound. C. Higher in frequency. D. Occasionally split. E. Heard when the ventricles are relaxing.

Answer»

A. False This applies to both heart sounds. 

B. False It is about 20 per cent shorter. 

C. True About 50 Hz compared with 35 Hz for the first sound. 

D. False Both may be split due to asynchronous valve closure. 

E. True The first sound is due to ventricular systole; the second occurs during ventricular relaxation when the aortic valves snap shut as ventricular pressure falls below aortic.

41.

Pulmonary vascular resistance is A. Less than one-third that offered by the systemic circuit. B. Decreased when alveolar oxygen pressure falls. C. Expressed in units of volume flow per unit time per unit pressure gradient. D. Decreased during exercise. E. Regulated reflexly by sympathetic vasoconstrictor nerves.

Answer»

A. True The pressure head needed to drive cardiac output through the pulmonary circuit (about 15 mmHg) is much less than that needed in the systemic circuit (about 90 mmHg). 

B. False The reverse is true; low alveolar PO2 may cause pulmonary hypertension. 

C. False These are conductance units, the reciprocal of resistance units. 

D. True Thus there is little rise in pulmonary arterial pressure during exercise despite the increased flow rate. Release of nitric oxide from the pulmonary vascular endothelium may account for the vasodilatation. 

E. False Pulmonary vascular resistance is controlled by local rather than by nervous mechanisms.

42.

Veins A. Contain most of the blood volume. B. Have a sympathetic vasoconstrictor innervation. C. Receive nutrition from vasa vasorum arising from their lumen. D. Respond to distension by contraction of their smooth muscle. E. Undergo smooth muscle hypertrophy when exposed to high pressure through an arteriovenous fistula. 

Answer»

A. True Around three-quarters; veins are referred to as ‘capacitance’ vessels. 

B. True These modulate venous capacity. 

C. False Their vasa arise from neighbouring arteries. 

D. True This ‘myogenic’ response helps to limit the degree of distension. 

E. True Another functional adaptation to resist distension.

43.

The particle P shown in the figure has a mass of 10 mg and a charge of `-0.01 muC`. Each plate has a surface area `10^(-2) m^2` on one side. What potential difference V should be applied to the combination to hold the particle P in equilibrium? A. `43 mV`B. `35 mV`C. ` 50 mV`D. `55 mV`

Answer» Correct Answer - A
`mg=qE,` where `E=` electric field
or `mg=q(V)/(d)` (where `d=` separation at the plates)
`=q(V)/(2) (therefore (epsilon_(0)A)/(d)=C(1)/(d)=(C)/(epsilon_(0)A))`
or `V=(2"mg"epsilon)A)/(qC)`
`=(10^(-4)xx10xx2.2xx10^(-12)xx10^(-2))/(10^(-8)xx0.04xx10^(-6))`
`=(10^(-4)xx9.8xx8.88xx10^(-12))/(10^(-4)xx0.04xx10^(-6))`
`=43mV`
44.

A point charge q is situated at X between two parallel plates which have a potential difference V and carry charges `+Q` and `-Q`. What is the electric field strength at X ? A. `V/d`B. `(Vq)/d`C. `Q/(4piepsilon_0a^2)`D. `(qQ)/(4piepsilon_0a^2)`

Answer» Correct Answer - A
The electric field strength in a parallel plate capacitor with applied voltage of `V` and separation `d` is given by `E=V//d`.
45.

In the heart A. The left atrial wall is about three times thicker than the right atrial wall. B. Systolic contraction normally begins in the left atrium. C. Excitation spreads directly from atrial muscle cells to ventricular muscle cells. D. Atrial and ventricular muscle contracts simultaneously in systole. E. The contracting ventricles shorten from apex to base.

Answer»

A. False Their wall thickness is similar since the workload of the two atria is similar. 

B. False It begins at the sinuatrial node in the right atrium. 

C. False Excitation can only pass from atria to ventricles via specialized conducting tissue in the AV bundle. 

D. False Delay of excitation in the AV bundle makes atrial precede ventricular contraction. 

E. True Due to the spiral arrangement of some muscle fibres; circular fibres reduce ventricular circumference. 

46.

In the brachial artery A. Pulse waves travel at the same velocity as blood. B. Pulse pressure falls with decreasing elasticity of the wall. C. Pressure rises markedly when the artery is occluded distally. D. Pressure falls when the arm is raised above head level. E. Pulse pressures have a smaller amplitude than aortic pulse pressures.

Answer»

A. False Pulse waves travel at about ten times the blood velocity. 

B. False It rises; arterial elasticity normally damps the pulse pressure. 

C. False Blood flows off rapidly via collaterals so that little pressure change occurs. 

D. True By the hydrostatic equivalent of the column of blood between it and the heart. 

E. False Brachial arterial pulse pressures are greater due to the superimposition of waves reflected from the end of the arterial tree.

47.

The Purkinje tissue cells in the heart A. Conduct impulses faster than some neurones. B. Are larger than ventricular myocardial cells. C. Lead to contraction of the base before the apex of the heart. D. Are responsible for the short duration of the QRS complex. E. Are responsible for the configuration of the QRS complex.

Answer»

A. True They conduct at around 4 metres/second. Small diameter nerve fibres conduct impulses at about 1 metre per second. 

B. True This facilitates rapid conduction. 

C. False Purkinje fibres travel to the apex before proceeding to the base of the heart. 

D. True They spread depolarization rapidly over the entire ventricular myocardium. 

E. True Damage to the cells (as in bundle-branch block) changes the pattern of spread of ventricular depolarization, and hence the shape of the QRS complex.

48.

The projection of vector, `vec(r)=3hat(i)+hat(j)+2hat(k)`, on the x-y plane has magnitude-A. `3`B. `4`C. `sqrt(14)`D. `sqrt(10)`

Answer» Correct Answer - D
Projection on x-y plane `=sqrt(3^(2)+1^(2))=sqrt(10)`
49.

If `vec(a) = 2hat(i) + 3hat(j) - 6hat(k)` and `vec(b) = 12 hat(j) + 5 hat(k)`. then (projection of `vec(a)` on `vec(b)//("projection of b on a")` )A. `7//13`B. `13//7`C. `20//13`D. `13//20`

Answer» Correct Answer - A
`vec(a) .vec(b) = ab cos theta`
projection of `vec(a)` on `vec(b) = a cos theta = (vec(a).vec(b))/(b)`
projection of `vec(b)` on `vec(a) = b cos theta = (vec(a).vec(b))/(a)`
`("projection of" vec(a) "on" vec(b))/("projection of"vec(b) "on" vec(a)) = ((vec(a).vec(b))/(b))/((vec(a).vec(b))/(a))`
`= (a)/(b) = (7)/(13)`
50.

A particle is moving from a point `(2m, 3m)` to `(1m, 1m)` under the influence of force with potential energy `U = lambda (x + y)`. If work done by the force is `n lambda`, then find the value of n.

Answer» Correct Answer - 3
`W_("conservative") = - Delta U = U_(i) - U_(f)`
`W_("conservative") = lambda (2 + 3) - lambda (1 + 1) = 3 lambda`