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If an 8Ω resistance and 6Ω reactance are present in an AC series circuit then the impedence of the circuit will be
Solution :- Z^2 = R^2 + X^2
Z = [(8)^2 + (6)^2]^½
Z = [100]^½
Z = 10 ohm
If the energy of hydrogen atom in ground state is -13.6 eV, then its energy in the first excited state will be
In which radioactive disintegration, neutron dissociates into proton and electron
The appropriate material to be used in the construction of resistance boxes out the following is
The resistance of an ammeter is 13 Ω and its scale is graduated for a current upto 100A. After an additional shunt has been connected to this ammeter it becomes possible to measure currents upto 750A by this meter. The value of shunt resistance is
An oxide coated filament is useful in vacuum tubes because essentially
In Thomson experiment of finding e/m for electrons, beam of electron is replaced by that of muons (particle with same charge as of electrons but mass 208 times that of electrons). No deflection condition in this case satisfied if
A 80 μF capacitor in a defibrillator is charged to 100 V. The energy stored in the capacitor is sent through the patient during a pulse of duration 2 ms. The power delivered to the patient is
The capacitance of a parallel plate capacitor is 10 μF when distance between its plates is 8 cm. If distance between the plates is reduced to 4 cm, its capacitance will be
A satellite whose mass is M, is revolving in circular orbit of radius r aroud the earth. Time of revolution of satellite is
Correct Answer : a
Explanation : Let the satellite of mass ms is revolving around the Earth of mass me at a distance of r then the centripetal force will be given by:
Fc = msv2/r
where v is velocity of satellite. This force is equal to gravitational force between satellite and earth. Therefore
(msv2)/r = (Gmsme)/r2
v = (Gme/r)1/2
Now, period of the satellite is given by:
T = 2πr/v
= 2π(r3/Gme)1/2
{2π is constant}
Therefore T is proportional to 2π(r3/Gme)1/2
Pulling force making an angle θ to the horizontal is applied on a block of weight W placed on a horizontal table. If the angle of friction is α. then the magnitude of force required to move the body is equal to
0.1m3 of water at 80o C is mixed with 0.3m3 of water at 60o C . The final temperature of the mixture is
At a given volume and temperture, the pressure of a gas
A cyclotron oscillator frequency is 10 MHz. If radius of its dees 60 cm, then magnetic field for accelerating the protons is (Given e = 1.6 x 10-19C, mp = 1.67 x 10-27 kg)
If a substance is to be paramagnetic, its atoms must have a
The change in surface energy, when a drop of surface tension T and radius of R splits into 1000 droplets of radius r, is
In a container, the velocity of water flowing through a hole at a depth h from the surface of water is 5 m-s⁻1. If the container has the hole at a depth 4h from the surface of water, then velocity of water flowing through the hole is
A copper wire of length 4 m and area of cross-section 1.2 cm2 is stretched with a force of 4.8 x 103 N. If the Young's modulus for copper is 1.2 x 1011 N-m⁻2, then increase in the length of the wire will be
A body, thrown upwards with some velocity, reaches the maximum height of 20 m. Another body with double the mass thrown up, with double initial velocity will reach a maximum height of
Which of the following does not represent a zero vector?
The parametric equations of a curve traced by a projectile on a certain planet with no surrounding are given by :y = (8t-5t2) metre and x = 6t metre, where t is in seconds. The velocity with which the projectile is projected, is
A parachutist of weight W strikes the ground with his logs fixed and comes to rest with an upward acceleration of magnitude '3g'. Force exerted on him by the ground during landing is
The kinetic energy of a particle executing simple harmonic motion is 16 J when it is in its mean position. If the amplitude of oscillation is 25 cm and the mass of the particle is 5.12 kg, the tme period of its oscillation is
The bob of a simple pendulum is a spherical hollow ball filled with water. A plugged hole near the bottom of the oscillating bob gets suddenly unplugged. During the observation, till water is coming out, the time period of oscillation would
With respect to air, critical angle in a medium for light of red colour [λ₁] is θ. Other facts remaining same, critical angle for light of yellow colour [λ₂] will be
A wheel having moment of inertia 2 kg-m2 about its vertical axis, rotates at the rate of 60 rev-min⁻1 about this axis. The torque, which can stop the wheel's rotation in one minute, would be
A mass of 2 kg tied to a string of 1m length is rotated in a vertical circle with a uniform speed of 4ms-1. The tension in the string will be 52N, when the mass is at
Before jumping in water from above, a swimmer bends his body to
An electric lamp is marked 60 W, 230 V. The cost of 1 kilowatt hour of power is Rs. 1.25. The cost of using this lamp for 8 hours is
A block of mass 100 gm slides on a rough horizontal surface. If the speed of the block decreases from 10 m/s to 5 m/s, the thermal energy developed in the process is
In which process the P-V indicator diagram is a straight line parallel to volume axis
If C and R denote the capacitance and resistance respectively, then the dimensional formula for CR is same as that fore
CR is time constant of CR circuit
Wave optics is based on wave theory of light put forward by Huygen and modified later by
In the propagation of light waves, the angle between the direction of vibration and plane of polarisation is
The velocity of waves in a string fixed at both ends is 2 m/s. The string forms standing waves with nodes 5.0 cm apart. The frequency of vibration of the string in Hz is
Two bodies have their resonant frequencies at 252 and 256 υib/sec respectively. The beat frequency produced when they vibrate together is
The earth's radius is R and acc. due to gravity at its surface is g. If a body of mass m falls from a height h = R/5 from earth's surface, its potential energy decreases by
A motor pump set lifts 300 Kg of water per minute from a well of depth 20 m and delivers to a height of 20 m. Then its power is
The general order of reactivity of carbonyl compounds towards nucleophilic addition reactions is?
In a given atom, no two electrons can have the same values of all the quantum numbers. This is called
Homolytic fission of C - C bond in ethane gives an intermediate in which carbon is
Homolytic fission of C — C bond gives free radicals in which carbon is sp2 hybridised.
The effect of atoms or groups loosing electrons towads a carbon atom is called
Carboxylic acids are more acidic than phenol and alcohol because of
A reversible reaction is said to have attained equilibrium, when
Al3+ has a higher nuclear charge (+ 13) and consequently the larger force of attraction by the nucleus for the valence shell electrons than that of Mg2+ (+ 12).
A graph plotted between log k versus 1/T for calculating activation energy is shown by
The transition elements are more metallic than the representative elements, because they are
Which of the following element belongs to the second row transition series?
In which cell of the free energy of a chemical reaction is directly converted into electricity ?
If the solubility of PbCl₂ at 25oC is 6.3 x 10⁻3 mole/litre, its solubility product at that temperature is
A compound A has a molecular formula C₂Cl₃OH. It reduces Fehling solution and on oxidation give a monocarboxylic acid B. A is obtained by the action of chlorine on ethyl alcohol. A is
Nitrogen atom has an atomic number of 7 and oxygen has an atomic number 8. The total number of electrons in a nitrate ion will be
Sea divers go deep into the sea water with a mixture of which of the following gases?
Sodium is made by the electrolysis of a molten mixture of about 40% NaCl and 60% CaCl₂ because
What are the products formed when Li2CO3 undergoes decomposition?
When the solute is present in trace quantities, the following expression is used
If two moles of an ideal gas at 546 K occupy volume of 44.8 L, then pressure must be
If 0.5g of metal on oxidation formed 0.79 g of its oxide, then equivalent weight of the metal is
According to the adsorption theory of catalysis, the speed of the reaction increases because
If the sum of the coefficients in the expansion of (α2x2 - 2αx + 1)51 vanishes, then α is equal to
The lines 3x - 4y + 4 = 0 and 6x - 8y - 7 = 0 are tangent to the same circle. The radius of this circle is
If the circles x2 + y2 = 9 and x + y + 2ax + 2y + 1 = 0 touch each other, then a is
The solution of differential equation (dy/dx)=[(1+y2)/(1+x2)] is
Sum of the given series:Sum of the given series:
AB is a vertical pole. The end A is on the level ground, C is the middle point of AB and P is a point on the level ground. The portion CB subtends an angle β at P. If AP=nAB, tanβ=
The line y = 4x + c touches the hyperbola x2 - y2 = 1 if
The area between (x2/a2) + (y2/b2) = 1 and the straight line (x/a) + (y/b) = 1 is
The area enclosed between the curve y2 = 4x and the line y = x is
If sin⁻1 x = π/5, for some x ∈[- 1, 1], then the value of cos⁻1 x is
If A and B are square matrices and A⁻1 and B⁻1 of same order exists, then (AB)⁻1 is equal to
B⁻1A⁻1.
Explanation:
Given that A and B are square matrices and their inverses A⁻1 and B⁻1 exist, we want to find the inverse of the product AB, denoted as (AB)⁻1.
To show that (AB)⁻1 = B⁻1A⁻1, we will demonstrate that (AB)(B⁻1A⁻1) = I and (B⁻1A⁻1)(AB) = I, where I is the identity matrix.
First, let's find the product (AB)(B⁻1A⁻1):
(AB)(B⁻1A⁻1) = A(BB⁻1)A⁻1 (associative property)
Since B and B⁻1 are inverses, their product BB⁻1 is the identity matrix:
A(IA⁻1) = A(A⁻1)
And because A and A⁻1 are inverses, their product AA⁻1 is the identity matrix:
if A is a 3 x 3 matrix and B is its adjoint matrix. If ∣B∣ = 64, then ∣A∣ =
If α , β are the roots of the quadratic equation x2 − (a − 2) x − (a + 1) = 0 , where a is a variable, then the least value of α2 + β2 is
The point represented by the complex number 2 - i is rotated about origin through an angle of π/2 in clockwise direction. The new position of the point is
A quadrilateral is formed by pairs of lines xy+x+y+1=0, xy+3x+3y+9=0, then quadrilateral is
Find the equation of the normal to curve x2=4y which passes through the point (1, 2).
On the parabola y2 = 8 x if one extremity of a focal chord is 1 ∕ 2, − 2 then its other extremity is
We have (n+1) white balls and (n+1) black balls. In each set the balls are numbered from 1 to (n+1). If these balls are to be arranged in a row so that two consecutive balls are of different colours, then the number of these arrangements is
Between (n + 1) white balls there are (n + 2) gaps in which (n + 1) black ball are to arranged.
No. of reqd arrangements = (n + 1)! (n + 1)! = [(n + 1)!]2
Now between (n + 1) black balls (n + 1) white balls are to be filled no. of ways
= (n + 1)! (n + 1)!
∴ Reqd ways = 2[(n + 1)!]2
An urn contains 9 balls two of which are red, three blue and four black. Three balls are drawn at random. The probability that they are of same colour is
A coin is tossed successively three times. The probability of getting at least 2 heads is:
In ΔABC , if a,b,c, are in A. P., then tan A/2 tan C/2 =
The sum of infinite terms of the G.P. √2 + 1/√2 - 1, 1/2 - √2, 1/2,... is
If the sum of the first n terms of a series be 5n2 + 2n, then its second term is
Let N denote the set of all natural numbers and R be the relation on N x N defined by (a,b)R(c,d) if ad(b+c)=bc(a+d), then R is
If A and B are matrices of order 2 such that A * B = (AB - BA)/2 then which of the following is false?
The equation of line passing through lines 5x-6y-1=0 and 3x+2y+5=0 and perpendicular to 3x-5y+11=0 is
The angle between the planes 2x - y + z = 6 and x + y + 2z = 7 is
The length of the subtangent to the curve x2+xy+y2=7 at (1,-3) is
The equation of the sphere passing thro' the point (1,3-2) and the circle y2+z2=25 and x=0 is
The general value of θ which satisfies tanθ=-1 and cosθ=(1/√2) the equations is
The perimeter of a triangle formed by 3i+4j+5k, 4i-3j-5k and 7i+j is
If |a|=3, |b|=4, |c|=5 are such that each is perpendicular to the sum of other two, then |a+b+c|=
Find the Antonym of the word occurring in the sentence in capital letter as per the context.
The two friends were DISTINCT in everything; dress manners, hair-style and food-habits.
DISTINCT here means 'different'
Find the Antonym of the word occurring in the sentence in capital letter as per the context.
For the first time I saw him speaking RUDELY to her
'Rudely' means showing lack of respect.
So its antonym will be Politely
Fill in the blank with appropriate word.
In hot weather I like lying in the........of a tree.
Fill in the blank with appropriate word.
This was the first time Roshan had been found guilty. He has no.......convictions
Choose the one which can be substituted for the given words/sentences
The policy of extending a country's empire and influence
Choose the one which can be substituted for the given words/sentences
A person who insists on something.
Yet, firms and other concerns are spending large sums of money all the time
Find the Synonym of the word occurring in the sentence in capital letter as per the context.
He is very intelligent, but ILL-FAVOURED by nature
Meaning of ILL-FAVOUR - bad tempered, intended meaning here is - She is intelligent but not good at her conduct
Choose the word which is least like the other words in the group .
Group the following figures into three classes on the basis of identical properties.
1,6,9 are figures which are half shaded by slanting lines
2,4,7 are all divided into equal parts (either three or four parts) by straight lines and also have a black circle at the centre.
3,5,8 have similar designs and have their four corners shaded black.
The above three numbers are multiples of the number at the bottom.
Clearly, 36, 18 and 27 are all multiples of 9.
So, the missing number is 9.
In each question, three sequences of letters/numerals are given which correspond to each other. Find out the letters/numerals that come in vacant places.
A _ B A C _ D _ B C D C
_ 3 _ 2 _ 1 _ 4 ? ? ? ?
d c _ _ b a c b _ _ _ _
In this letter series, some of the letters are missing. Choose the correct letter given below -
ab _ aa _ caab _ c _ abb _ c
Please go through following and answer question no.128 to no.131
The practice of appointing educated persons to join under government began more than a hundred and thirty years ago as a method of encouraging people to go in for the new system of education that had been established by the colonial administration. It worked well till about 1921 because expansion of jobs under the government could still keep pace with the output of the educational system. But since then, the undesirable consequences of this approach have come to the fore. To begin with, it over emphasizes the bread and butter objective of education and makes it a ladder which enables the ambitious to climb into privilege, even as it devalues the academic objective-the development of individuals dedicated to the pursuit of scholarship. Moreover, hunt for a place in the privileged sector or a well-paid and secure job in the organized sector creates immense pressure for the expansion of secondary and higher education because they grow more in terms of the large numbers of aspirants for jobs rather than in relation to the small number of jobs available. This necessarily leads to an over-production of college graduates and to large-scale unemployment of the educated.
Which one of the following statements is correct?
Educated persons were given jobs under the government, more than a century ago, so that the young people
The practice of appointing educated persons to join under government began more than a hundred and thirty years ago as a method of encouraging people to go in for the new system of education that had been established by the colonial administration. It worked well till about 1921 because expansion of jobs under the government could still keep pace with the output of the educational system. But since then, the undesirable consequences of this approach have come to the fore. To begin with, it over emphasizes the bread and butter objective of education and makes it a ladder which enables the ambitious to climb into privilege, even as it devalues the academic objective-the development of individuals dedicated to the pursuit of scholarship. Moreover, hunt for a place in the privileged sector or a well-paid and secure job in the organized sector creates immense pressure for the expansion of secondary and higher education because they grow more in terms of the large numbers of aspirants for jobs rather than in relation to the small number of jobs available. This necessarily leads to an over-production of college graduates and to large-scale unemployment of the educated.
Which one of the following statements is correct?
129. Which one of the following statements is correct?
The policies of the colonial administration were effective till about 1921 because
The practice of appointing educated persons to join under government began more than a hundred and thirty years ago as a method of encouraging people to go in for the new system of education that had been established by the colonial administration. It worked well till about 1921 because expansion of jobs under the government could still keep pace with the output of the educational system. But since then, the undesirable consequences of this approach have come to the fore. To begin with, it over emphasizes the bread and butter objective of education and makes it a ladder which enables the ambitious to climb into privilege, even as it devalues the academic objective-the development of individuals dedicated to the pursuit of scholarship. Moreover, hunt for a place in the privileged sector or a well-paid and secure job in the organized sector creates immense pressure for the expansion of secondary and higher education because they grow more in terms of the large numbers of aspirants for jobs rather than in relation to the small number of jobs available. This necessarily leads to an over-production of college graduates and to large-scale unemployment of the educated.
Which one of the following statements is correct?
Which one of the following statements is correct?
The system failed later on because
The practice of appointing educated persons to join under government began more than a hundred and thirty years ago as a method of encouraging people to go in for the new system of education that had been established by the colonial administration. It worked well till about 1921 because expansion of jobs under the government could still keep pace with the output of the educational system. But since then, the undesirable consequences of this approach have come to the fore. To begin with, it over emphasizes the bread and butter objective of education and makes it a ladder which enables the ambitious to climb into privilege, even as it devalues the academic objective-the development of individuals dedicated to the pursuit of scholarship. Moreover, hunt for a place in the privileged sector or a well-paid and secure job in the organized sector creates immense pressure for the expansion of secondary and higher education because they grow more in terms of the large numbers of aspirants for jobs rather than in relation to the small number of jobs available. This necessarily leads to an over-production of college graduates and to large-scale unemployment of the educated.
Which one of the following statements is correct?
The expansion of secondary and higher education leads to which one of the following?
Select the correct mirror image of the figure (X) from amongst the given alternatives.
Select the correct mirror image of the figure (X) from amongst the given alternatives.
Each of the following questions consists of five Problem figures marked 1,2,3,4 and 5 followed by five Answer figures marked A,B,C,D and E . Select a figure from the Answer figures which will continue the same series as given in the Problem figures.