Q 1PhysicsSection A • MCQelectrostatics
+4 / -1The electric potential at the centre of two concentric half rings of radii R and R, having same linear charge density is :
A
B
C
D
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The electric potential at the centre of two concentric half rings of radii R and R, having same linear charge density is :
A long solenoid is formed by winding 70 turns cm. If 2.0 A current flows, then the magnetic field produced inside the solenoid is ____________ ( TmA)
A photon is emitted in transition from n = 4 to n = 1 level in hydrogen atom. The corresponding wavelength for this transition is (given, h = 4 10 eVs) :
A mass m attached to free end of a spring executes SHM with a period of 1s. If the mass is increased by 3 kg the period of the oscillation increases by one second, the value of mass m is ___________ kg.
A uniform solid cylinder with radius R and length L has moment of inertia I, about the axis of the cylinder. A concentric solid cylinder of radius and length is carved out of the original cylinder. If I is the moment of inertia of the carved out portion of the cylinder then __________.
(Both I and I are about the axis of the cylinder)
The electric field and magnetic field components of an electromagnetic wave going through vacuum is described by
Then the correct relation between E and B is given by
If two vectors and are perpendicular to each other. Then, the value of m will be :
Three identical resistors with resistance R = 12 and two identical inductors with self inductance L = 5 mH are connected to an ideal battery with emf of 12 V as shown in figure. The current through the battery long after the switch has been closed will be _____________ A.
A body of mass 200g is tied to a spring of spring constant 12.5 N/m, while the other end of spring is fixed at point O. If the body moves about O in a circular path on a smooth horizontal surface with constant angular speed 5 rad/s. Then the ratio of extension in the spring to its natural length will be :
The velocity time graph of a body moving in a straight line is shown in the figure.
The ratio of displacement to distance travelled by the body in time 0 to 10s is :
When a beam of white light is allowed to pass through convex lens parallel to principal axis, the different colours of light converge at different point on the principle axis after refraction. This is called :
A single turn current loop in the shape of a right angle triangle with sides 5 cm, 12 cm, 13 cm is carrying a current of 2 A. The loop is in a uniform magnetic field of magnitude 0.75 T whose direction is parallel to the current in the 13 cm side of the loop. The magnitude of the magnetic force on the 5 cm side will be N. The value of is ____________.
Let be the ratio of molar specific heat at constant pressure and molar specific heat at constant volume of a monoatomic gas and be the similar ratio of diatomic gas. Considering the diatomic gas molecule as a rigid rotator, the ratio, is :
The energy released per fission of nucleus of X is 200 MeV. The energy released if all the atoms in 120g of pure X undergo fission is ____________ 10 MeV.
(Given )
A Spherical ball of radius 1mm and density 10.5 g/cc is dropped in glycerine of coefficient of viscosity 9.8 poise and density 1.5 g/cc. Viscous force on the ball when it attains constant velocity is N. The value of is ________.
(Given, g = 9.8 m/s and )
The frequency () of an oscillating liquid drop may depend upon radius () of the drop, density () of liquid and the surface tension (s) of the liquid as . The values of a, b and c respectively are
Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R
Assertion A : Steel is used in the construction of buildings and bridges.
Reason R : Steel is more elastic and its elastic limit is high.
In the light of above statements, choose the most appropriate answer from the options given below
A convex lens of refractive index 1.5 and focal length 18cm in air is immersed in water. The change in focal length of the lens will be ___________ cm.
(Given refractive index of water )
Given below are two statements:
Statement I : Acceleration due to earth's gravity decreases as you go 'up' or 'down' from earth's surface.
Statement II : Acceleration due to earth's gravity is same at a height 'h' and depth 'd' from earth's surface, if h = d.
In the light of above statements, choose the most appropriate answer from the options given below
Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A : A pendulum clock when taken to Mount Everest becomes fast.
Reason R : The value of g (acceleration due to gravity) is less at Mount Everest than its value on the surface of earth.
In the light of the above statements, choose the most appropriate answer from the options given below
A parallel plate capacitor with air between the plate has a capacitance of 15pF. The separation between the plate becomes twice and the space between them is filled with a medium of dielectric constant 3.5. Then the capacitance becomes pF. The value of is ____________.
If a copper wire is stretched to increase its length by 20%. The percentage increase in resistance of the wire is __________%.
A metallic rod of length 'L' is rotated with an angular speed of '' normal to a uniform magnetic field 'B' about an axis passing through one end of rod as shown in figure. The induced emf will be :
Match List I with List II
| List-I |
List-II |
||
|---|---|---|---|
| A. | AM Broadcast | I. | 88-108 MHz |
| B. | FM Broadcast | II. | 540-1600 kHz |
| C. | Television | III. | 3.7-4.2 GHz |
| D. | Satellite Communication | IV. | 54MHz - 890MHz |
Choose the correct answer from the options given below :
A cell of emf 90 V is connected across series combination of two resistors each of 100 resistance. A voltmeter of resistance 400 is used to measure the potential difference across each resistor. The reading of the voltmeter will be :
In an Isothermal change, the change in pressure and volume of a gas can be represented for three different temperature; as :
The logic gate equivalent to the given circuit diagram is :
A body of mass 1kg begins to move under the action of a time dependent force N, where and are the unit vectors along and axis. The power developed by above force, at the time t = 2s, will be ____________ W.
If the distance of the earth from Sun is 1.5 10 km. Then the distance of an imaginary planet from Sun, if its period of revolution is 2.83 years is :
The number of units, which are used to express concentration of solutions from the following is _________
Mass percent, Mole, Mole fraction, Molarity, ppm, Molality
Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion A : Benzene is more stable than hypothetical cyclohexatriene
Reason R : The delocalised electron cloud is attracted more strongly by nuclei of carbon atoms.
In the light of the above statements, choose the correct answer from the options given below:
Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion A : Beryllium has less negative value of reduction potential compared to the other alkaline earth metals.
Reason R : Beryllium has large hydration energy due to small size of Be but relatively large value of atomization enthalpy
In the light of the above statements, choose the most appropriate answer from the options given below :
Identify the correct statements about alkali metals.
A. The order of standard reduction potential (M | M) for alkali metal ions is Na > Rb > Li.
B. CsI is highly soluble in water.
C. Lithium carbonate is highly stable to heat.
D. Potassium dissolved in concentrated liquid ammonia is blue in colour and paramagnetic.
E. All the alkali metal hydrides are ionic solids.
Choose the correct answer from the options given below :
The total pressure observed by mixing two liquids A and B is 350 mm Hg when their mole fractions are 0.7 and 0.3 respectively.
The total pressure becomes 410 mm Hg if the mole fractions are changed to 0.2 and 0.8 respectively for A and B. The vapour pressure of pure A is __________ mm Hg. (Nearest integer)
Consider the liquids and solutions behave ideally.
Total number of tripeptides possible by mixing of valine and proline is ___________
In which of the following reactions the hydrogen peroxide acts as a reducing agent?
Which of the following cannot be explained by crystal field theory?
Find out the major products from the following reactions.
Given below are two statements:
Statement I : Pure Aniline and other arylamines are usually colourless.
Statement II : Arylamines get coloured on storage due to atmospheric reduction.
In the light of the above statements, choose the most appropriate answer from the options given below :
The number of statement/s, which are correct with respect to the compression of carbon dioxide from point (a) in the Andrews isotherm from the following is ___________
A. Carbon dioxide remains as a gas upto point (b)
B. Liquid carbon dioxide appears at point (c)
C. Liquid and gaseous carbon dioxide coexist between points (b) and (c)
D. As the volume decreases from (b) and (c), the amount of liquid decreases
The hybridization and magnetic behaviour of cobalt ion in complex, respectively is :
One mole of an ideal monoatomic gas is subjected to changes as shown in the graph. The magnitude of the work done (by the system or on the system) is __________ J (nearest integer)
Given ;
If the pKa of lactic acid is 5, then the pH of 0.005 M calcium lactate solution at 25C is ___________ 10 (Nearest integer)
Following figure shows spectrum of an ideal black body at four different temperatures. The number of correct statement/s from the following is ____________.
A.
B. The black body consists of particles performing simple harmonic motion.
C. The peak of the spectrum shifts to shorter wavelength as temperature increases.
D. constant
E. The given spectrum could be explained using quantisation of energy.
The number of s-electrons present in an ion with 55 protons in its unipositive state is
Sum of -bonds present in peroxodisulphuric acid and pyrosulphuric acid is ___________
The number of statement/s which are the characteristics of physisorption is __________
A. It is highly specific in nature
B. Enthalpy of adsorption is high
C. It decreases with increase in temperature
D. It results into unimolecular layer
E. No activation energy is needed
The metal which is extracted by oxidation and subsequent reduction from its ore is :
Given below are two statements :
In the light of the above statements, choose the correct answer from the options given below:
Correct statement is :
paper acidified with dilute turns green when exposed to :
Maximum number of isomeric monochloro derivatives which can be obtained from 2,2,5,5-tetramethylhexane by chlorination is _____________
Match List I with List II
| List-I Type |
List-II Name |
||
|---|---|---|---|
| A. | Antifertility drug | i) | Norethindrone |
| B. | Tranquilizer | ii) | Meprobomate |
| C. | Antihistamine | iii) | Seldane |
| D. | Antibiotic | iv) | Ampicillin |
Choose the correct answer from the options given below :
Which will undergo deprotonation most readily in the basic medium?
Which one amongst the following are good oxidizing agents?
A. Sm
B. Ce
C. Ce
D. Tb
Choose the most appropriate answer from the options given below :
A student has studied the decomposition of a gas AB at 25C. He obtained the following data.
| p (mm Hg) | 50 | 100 | 200 | 400 |
|---|---|---|---|---|
| relative t (s) | 4 | 2 | 1 | 0.5 |
The order of the reaction is
What is the number of unpaired electron(s) in the highest occupied molecular orbital of the following species : ?
Choose the correct colour of the product for the following reaction.
Choose the correct representation of conductometric titration of benzoic acid vs sodium hydroxide.
The number of integers, greater than 7000 that can be formed, using the digits 3, 5, 6, 7, 8 without repetition is :
Let . Then is equal to __________.
Let be a function such that for all . If and , then the value of n is
The minimum number of elements that must be added to the relation R = {(a, b), (b, c), (b, d)} on the set {a, b, c, d} so that it is an equivalence relation, is __________.
If the system of equations
has infinitely many solutions, then the ordered pair () is equal to :
Let p and q be two statements. Then is equivalent to
Let be the solution of the differential equation . Then is equal to
If the shortest between the lines and is 6, then the square of sum of all possible values of is :
The value of is
If the foot of the perpendicular drawn from (1, 9, 7) to the line passing through the point (3, 2, 1) and parallel to the planes and is (), then is equal to :
Let be differentiable function defined on such that and . Then is equal to __________.
The number of square matrices of order 5 with entries from the set {0, 1}, such that the sum of all the elements in each row is 1 and the sum of all the elements in each column is also 1, is :
If the area of the region bounded by the curves is A, then 8 A is equal to __________
is equal to :
The number of real solutions of the equation , is
Let the plane containing the line of intersection of the planes
P1 : and
P2 :
pass through the points (0, 1, 0) and (1, 0, 1). Then the distance of
the point (2) from the plane P2 is :
Let . Then is equal to :
Let and . Let be parallel to and be perpendicular to . If , then the value of is :
If , then the value of is
If , then is equal to
The set of all values of for which , where [] denotes the greatest integer less than or equal to is equal to
If then is equal to :
Three urns A, B and C contain 4 red, 6 black; 5 red, 5 black; and red, 4 black balls respectively. One of the urns is selected at random and a ball is drawn. If the ball drawn is red and the probability that it is drawn from urn C is 0.4 then the square of the length of the side of the largest equilateral triangle, inscribed in the parabola with one vertex at the vertex of the parabola, is :
If , then
The equations of the sides AB and AC of a triangle ABC are and respectively. Its vertex A is on the y-axis and its orthocentre is (1, 2). The length of the tangent from the point C to the part of the parabola in the first quadrant is :
Let the six numbers , be in A.P. and . If the mean of these six numbers is and their variance is , then 8 is equal to :
The equations of the sides AB, BC and CA of a triangle ABC are : and respectively. Let P(2, a) be the centroid of ABC. Then (BC) is equal to ___________.
Let the sum of the coefficients of the first three terms in the expansion of , be 376. Then the coefficient of is __________.
Let A be a 3 3 matrix such that . Then is equal to
The locus of the mid points of the chords of the circle which subtend an angle at the centre of the circle , is a circle of radius . If and , then is equal to :
