13875.A rigid ball of mass m strikes a rigid wall at 60º and gets reflected without loss of speed as shown in the figure below. The value of impulse imparted by the wall in the ball will be
$\dfrac{mV}{3}$
mV
2mV
$\dfrac{mV}{2}$
Explanation:
J = 2mV cos 60º = mV
13886.Two identical bodies are made of a material for which the heat capacity increases with temperature. One of these is at 100 ºC, while the other one is at 0 ºC. If the two bodies are brought into contact, then assuming no heat loss, the final common temperature is
0 ºC
50 ºC
more than 50 ºC
less than 50 ºC but greater than 0 ºC
Explanation:
Body at 100°C temperature has greater heat capacity than body at 0°C so final temperature will be closer to 100°C. So, Tc > 50°C
13893.Three sound waves of equal amplitudes have frequencies (n – 1), n, (n + 1). They superimpose to give beats. The number of beats produced per second will be
2
1
4
3
Explanation:
no. of beats = 1 (HCF of beat frequencies)
13898.A long wire carrying a steady current is bent into a circular loop of one turn. The magnetic field at the centre of the loop is B. It is then bent into a circular coil of n turns. The magnetic field at the centre of this coil of n turns will be
15782.Assertion: A cell membrane shows fluid behaviour. Reason: A membrane is a mosaic or composite of diverse lipids and proteins.
Both Assertion and Reason are true and the Reason is the correct explanation of the Assertion.
Both Assertion and Reason are true but the Reason is not the correct explanation of the Assertion.
Assertion is true statement but Reason is false.
Both Assertion and Reason are false statements.
15868.The given graph shows the effect of substrate concentration on the rate of reaction of the enzyme green gram-phosphatase. What does the graph indicate?
The rate of enzyme reaction is directly proportional to the substrate concentration
Presence of an enzyme inhibitor in the reaction mixture
Formation of an enzyme-substrate complex
At higher substrate concentration the pH increases
Explanation:
Glucose is called principle carbohydrate, sucrose is called translocable carbohydrate, starch is called storage carbohydrate and cellulose is called structural carbohydrate.
19182.Which one of the following in endangered species?
Cuscuta
Nepenthes
Datura
Butea sps.
19233.Global agreement in specific control strategies to reduce the release of ozone depleting substances, was adopted by
The Vienna Convention
Rio de Janeiro Conference
The Montreal Protocol
The Koyoto Protocol
19280.Which one of the following is the correct percentage of the two (out of the total of 4) green house gases that contribute to the total global warming?
CO2 40%,CFCs 30%
CFCs 14%, Methane 20%
Methane 20%, N2O 18%
N2O 6%, CO2 86%
21227.The maximum number of electrons that can have principal quantum number, n = 3, and spin quantum number, ms = $-\dfrac{1}{2}$, is
5
7
9
11
21242.How many 'd' electrons are present in Cr2+ ion?
4
5
6
3
21253.With increase in principal quantum number n, the energy difference between adjacent energy levels in hydrogen atom
increases
decreases
remain constant
decreases for lower values of n and increases for higher values of n
21270.The frequency of light emitted for the transition n = 4 to n = 2 of He+ is equal to the transition in H atom corresponding to which of the following?
n = 4 to n = 3
n = 3 to n = 1
n = 2 to n = 1
n = 3 to n = 2
21273.Consider the ground state of Cr atom (Z = 24). The numbers of electrons with the azimuthal quantum numbers, l = 1 and 2 are, respectively:
12 and 4
12 and 5
16 and 4
16 and 5
21279.If the wavelength of an electromagnetic radiation is 2000Å, what is its energy in ergs?
9.94 × 10–12
9.94 × 10–10
4.97 × 10–12
4.97 × 10–19
21284.In Hydrogen atom, energy of first excited state is – 3.4 eV. Then find out KE of same orbit of Hydrogen atom.
21401.For one mole of an ideal gas the slope of V vs. T curve at constant pressure of 2 atm is X lit mol–1 K–1. The value of the ideal universal gas constant ‘R’ in terms of X is
X lit atm mol–1K–1
X/2 lit atm mol–1K–1
2X lit atm mol–1K–1
2X atm lit–1mol–1K–1
21410.4 grams of an ideal gas occupies 5.6035 liters of volume at 546 K and 2 atm pressure. What is its molecular weight?
4
16
32
64
21420.At 27°C a closed vessel contains equal weight of He, CH4 and SO2 exerts a pressure of 210 mm and partial pressures of He, CH4 and SO2 are P1, P2 and P3. Which one of the following is correct?
P3 > P2 > P1
P1 > P2 > P3
P1 > P3 > P2
P2 > P3 > P1
21489.The value of ΔH for cooling 2 mole of an ideal monoatomic gas from 225°C to 125°C at constant pressure will be (given Cp = 5/2 R)
250 R
–500 R
500 R
–250 R
21568.The equilibrium constants $\text{K}_{P_{1}}$ and $\text{K}_{P_{1}}$ for the reactions
X ⇌ 2Y and Z ⇌ P + Q
respectively are in the ratio of 1 : 9. If the degree of dissociation of X and Z be equal then the ratio of total pressure at these equilibria is
1 : 36
1 : 1
1 : 3
1 : 9
21573.For the reaction 2HI(g) ⇌ H2(g) + I2(g) – QKJ, the equilibrium constant depends upon
21736.A compound contains two types of atoms X and Y. It crystallizes in a cubic lattice with atoms X at the corners of the unit cell and atoms Y at the body centre. The simplest possible formula of this compound is:
X8Y
X2Y
XY
XY8
21752.AB is an ionic solid. If the ratio of ionic radii of A+and B– is 0.52. What is the coordination number of B–?
6
3
2
8
21759.In a face centred cubic lattice, atom A occupies the corner positions and atom B occupies the face centre positions. If one atom of B is missing from one of the face centred points, the formula of the compound is
A2B5
A2B
AB2
A2B3
21767.Silver (atomic weight = 108 g mol–1) has a density of 10.5 g cm–3. The number of silver atoms on a surface of area 10–12 m2 can be expressed in scientific notation as y × 10$x$. The value of $x$ is
13
9
7
5
21822.The Henry's law constant for the solubility of N2 gas in water at 298 K is 1.0 × 105 atm. The mole fraction of N2 in air is 0.8. The number of moles of N2 from air dissolved in 10 moles of water at 298 K and 5 atm pressure is
4.0 × 10–4
4.0 × 10–5
5.0 × 10–4
4.0 × 10–6
21841.Volume of water needed to mix with 10 mL N HCl to get 0.1 N HCl is
90 mL
9 mL
900 mL
1000 mL
21870.One gram of silver gets distributed between 10 cm3 of molten zinc and 100 cm3 of molten lead at 800°C. The percentage of silver still left in the lead layer is approximately
5
2
1
3
22306.Accumulation of lactic acid (HC3H5O3), a monobasic acid in tissues leads to pain and a feeling of fatigue. In a 0.10 M aqueous solution, lactic acid is 3.7% dissociates. The value of dissociation constant, Ka, for this acid will be:
2.8 × 10–4
1.4 × 10–5
1.4 × 10–4
3.7 × 10–4
22384.The half life period of a first order chemical reaction is 6.93 minutes. The time required for the completion of 99% of the chemical reaction will be (log 2 = 0.301)
230.3 minutes
23.03 minutes
46.06 minutes
460.6 minutes
22426.Gold numbers of protective colloids A, B, C and D are 0.50, 0.01, 0.10 and 0.005 respectively. The correct order of their protective powers is
B < D < A < C
D < A < C < B
C < B < D < A
A < C < B < D
22495.Which one of the following molecules is expected to exhibit diamagnetic behaviour?
C2
N2
O2
S2
22505.Which do not decolourise KMnO4 aqueous solution?
C2O– 4
HSO– 3
CO2– 3
SO2– 3
22564.Which of the following compounds shows optical isomerism?
22854.Three dimensional molecules with cross links are formed in the case of a _____.
Thermoplastic
Thermosetting plastic
Both A and B
None of these
22899.Which of the following is an anionic detergent?
Sodium lauryl sulphate
Cetyltrimethyl ammonium bromide
Glyceryl oleate
Sodium stearate
22921.Which of the following compounds is not an antacid?
Aluminium Hydroxide
Cimetidine
Phenelzine
Ranitidine
23259.A physical quantity Q is found to depend on observables x, y and z, obeying relation $Q = \dfrac{x^3y^2}{z}$. The percentage error in the measurements of x, y and z are 1%, 2% and 4% respectively. What is percentage error in the quantity Q?
4%
3%
11%
1%
23316.A particle is moving along a circular path. Let $v$, ω, α and ac be its linear velocity, angular velocity, angular acceleration and centripetal acceleration respectively. Which is the wrong statement from the following?
23320.A particle moving in a circle of radius 25 cm at 2 revolutions per second. The acceleration of the particle is S.I. unit is
4$π$2
3$π$2
2$π$2
$π$2
23327.A motor cyclist moving with a velocity of 75 km/hr on a flat road takes a turn on the road at a point where the radius of curvature of the road is 20 m. If the g is 10 m/s2 the maximum angle of banking with vertical for no skidding is
tan–1 (6)
tan–1 (2)
tan–1 (12)
tan–1 (4)
23356.The maximum safe speed for a vehicle taking a turn on a curved banked road, does not depend upon
acceleration due to gravity
mass of the vehicle
angle of inclination (θ) with the horizontal
radius of curvature of the track
23382.A machine gun fires a bullet of mass 40 g with a velocity 1200 ms–1. The man holding it can exert a maximum force of 144 N on the gun. How many bullets can he fire per second at the most?
One
Two
Three
Four
23384.The force F acting on a particle of mass m is indicated by the force–time graph shown below. The change in momentum of the particle over the time interval from zero to 8 s is
24 Ns
20 Ns
12 Ns
6 Ns
23410.A particle of mass m is driven by a machine that delivers a constant power k watts. If the particle starts from rest the force on the particle at time t is
$\sqrt{\dfrac{mk}{2}} t^{–\dfrac{1}{2}}$
$\sqrt{mk} t^{–\dfrac{1}{2}}$
$\sqrt{2mk} t^{–\dfrac{1}{2}}$
$\dfrac{1}{2}\sqrt{mk} t^{–\dfrac{1}{2}}$
23421.Statement–1 : When ultraviolet light is incident on a photocell, its stopping potential is V0 and the maximum kinetic energy of the photoelectrons is Kmax. When the ultraviolet light is replaced by X–rays, both V0 and Kmax increase. Statement–2 : Photoelectrons are emitted with speeds ranging from zero to a maximum value because of the range of frequencies present in the incident light.
Statement–1 is true, Statement–2 is false
Statement–1 is false, Statement–2 is true
Statement–1 is true, Statement–2 is true; Statement–2 is the correct explanation of Statement–1
Statement–1 is true, Statement–2 is true; Statement–2 is the not the correct explanation of Statement–1
23423.According to Einstein s photoelectric equation, the plot of the kinetic energy of the emitted photoelectrons from a metal Vs the frequency, of the incident radiation gives a straight line whose slope:
depends on the nature of the metal used
depends on the intensity of the radiation
depends both on the intensity of the radiation and the metal used
is the same for all metals and independent of the intensity of the radiation
23427.If the momentum of an electron is changed by P, then the de Broglie wavelength associated with it changes by 0.5%. The initial momentum of electron will be
200 P
400 P
P/200
100 P
23429.A certain metallic surface is illuminated with monochromatic light of wavelength λ. The stopping potential for photo–electric current for this light is 3V0. If the same surface is illuminated with light of wavelength 2λ, the stopping potential is V0. The threshold wavelength for this surface for photoelectric effect is
6λ
4λ
λ/4
λ/6
23461.A potentiometer circuit has been set up for finding the internal resistance of a given cell. The main battery, used across the potentiometer wire, has an emf of 2.0 V and a negligible internal resistance. The potentiometer wire itself is 4 m long. When the resistance, R, connected across the given cell, has values of (i) Infinity (ii) 9.5 Ω, the balancing lengths on the potentiometer wire are found to be 3 m and 2.85 m, respectively. The value of internal resistance of the cell is
0.25 Ω
0.95 Ω
0.5 Ω
0.75 Ω
23468.Three resistances 2 Ω, 3 Ω and 4 Ω are connected in parallel. The ratio of currents passing through them when a potential difference is applied across its ends will be
5 : 4 : 3
6 : 3 : 2
4 : 3 : 2
6 : 4 : 3
23484.The Kirchhoff’s first law (Σi = 0) and second law (ΣiR = ΣE), where the symbols have their usual meanings, are respectively based on
conservation of charge, conservation of energy
conservation of charge, conservation of momentum
conservation of energy, conservation of charge
conservation of momentum, conservation of charge
23488.When 5 V potential difference is applied across a wire of length 0.1 m, the drift speed of electrons is 2.5 × 10–4 ms–1. If the electron density in the wire is 8 × 1028 m–3, the resistivity of the material is close to
1.6 × 10–8 Ωm
1.6 × 10–7 Ωm
1.6 × 10–6 Ωm
1.6 × 10–5 Ωm
23491.A 5V battery with internal resistance 2 Ω and a 2V battery with internal resistance 1 Ω are connected to a 10 Ω resistor as shown in the figure.
The current in the 10 Ω resistor is
0.03 A P1 to P2
0.03 A P2 to P1
0.27 A P1 to P2
0.27 A P2 to P1
23512.A charged particle moves through a magnetic field perpendicular to its direction. Then
the momentum changes but the kinetic energy is constant
both momentum and kinetic energy of the particle are not constant
both momentum and kinetic energy of the particle are constant
kinetic energy changes but the momentum is constant
23525.The magnetic lines of force inside a bar magnet
are from north–pole to south–pole of the magnet.
do not exist.
depend upon the area of cross–section of the bar magnet.
are from south–pole to north–pole of the magnet.
23529.A magnetic needle is kept in a non–uniform magnetic field. It experiences
a torque but not a force
neither a force nor a torque
a force and a torque
a force but not a torque
23533.If an electron and a proton having same momenta enter perpendicularly to a magnetic field, then
curved path of electron and proton will be same (ignoring the sense of revolution)
they will move undeflected
curved path of electron is more curved than that of the proton
path of proton is more curved
26082.Which one of the following cell organelles is enclosed by a single membrane?
Nuclei
Mitochondria
Chloroplasts
Lysosomes
Explanation:
Lysosomes is enclosed by a single membrane while Mitochondria, Chloroplasts and Nuclei are enclosed by double membrane.
26125.A unit mass of solid converted to liquid at its melting point. Heat is required for this process is
Specific heat
Latent heat of vaporization
Latent heat of fusion
External latent heat
26129.The specific heat of a gas in isothermal process is
Zero
Negative
Remains constant
Infinite
26154.The root mean square speed of hydrogen molecules at 300K is 1930 m/s. then the root mean square speed of oxygen molecule at 900K will be
1930$\sqrt{3}$ m/s
838 m/s
643 m/s
$\dfrac{1930}{\sqrt{3}}$ m/s
26180.The r.m.s velocity of oxygen molecules at 27°C is 318 m/s. the r.m.s velocity of hydrogen molecules at 127°C is
1470 m/s
1603 m/s
1869 m/s
2240 m/s
26195.Translational kinetic energy of gas molecule, for one mole of the gas, is equal to
$\dfrac{3}{2}RT$
$\dfrac{2}{3}KT$
$\dfrac{1}{2}RT$
$\dfrac{2}{1}KT$
26200.Which of the following is the unit of specific heat?
J kg/°C
J/kg°C
kg °C/J
J kg/°C2
26209.The distance of Neptune and Saturn from the sun are nearly 1013 m and 1012 m respectively. Assuming that they move in circular orbits, their periodic times would be in the ratio of
10
100
10 $\sqrt{10}$
1000
26212.If the earth is 1/4th of its present distance from the sun, the duration of the year would be
1/4 of the present year
1/6 of the present year
1/8 of the present year
1/16 of the present year
26227.Who among the following first gave the experimental velocity of G?
Cavendish
Copernicus
Brook Taylor
none of these
26240.The escape velocity from earth is 11.2 km per sec. If a body is to be projected in a direction making an angle 45° to the vertical, then the escape velocity is
11.2 × 2 km/sec
11.2 km/sec
11.2 ×$\dfrac{1}{\sqrt{2}}$ km/sec
11.2 ×${\sqrt{2}}$ km/sec
26249.If the change in the value of g at the height h above the surface of the earth is the same as at a depth x below it, then (both x and h being much smaller than the radius of the earth)
x = h
x = 2 h
x = $\dfrac{h}{2}$
x = h2
26254.Heat energy received by the earth from the sun is due to
Convection
Radiation
Reflection of light
Transmission of light
26274.Co-efficient of reflection, coefficient of absorption and coefficient transmission are related as
a + r + 1 = 1
a + r + t = 1
a + r = -t
a ≠ r + 1
26279.A body cools from 50°C to 46°C in 5 minutes and to 40°C in the next 10 minutes. The surrounding temperature is
30°C
28°C
36°C
32°C
26298.Three black bodies A, B and C in the form of cubes of sides in the ratio of 3: 4: 5 are kept at the same high temperature. The ratio of the quantity of heat lost per second by A, B and C will be
27: 64: 125
5: 4: 3
9: 16: 25
25: 16: 9
26326.Radiation emitted by a surface is directly proportional to
Third power of its temperature
Equal to its temperature
Twice power of its temperature
Fourth power of its temperature
26332.A sphere cube and a thin circular plate all made of the same material and having the same mass are initially heated to a temperature of 300°C. which of these cools fastest?
Sphere
Cube
Plate
None of these
26335.The temperature of a piece of metal is raised from 27°C to 51.2°C. the rate at which metal radiates energy increases nearly
1.36 times
2.36 times
3.36 times
4.36 times
26338.A body cools from 100°C to 70°C in 8 minutes. If the room temperature is 15°C and assuming Newton’s law of cooling holds good, then time required for the body to cool from 70°C to 40°C is