46809.Light of wavelength $\\lambda$ and photon energy 2 eV falling on a metal surface produces
photoelectrons of maximum velocity v. If $\\lambda$ is decreased by 25% and the maximum velocity is doubled,
the work function of metal (in eV) is
photoelectrons of maximum velocity v. If $\\lambda$ is decreased by 25% and the maximum velocity is doubled,
the work function of metal (in eV) is
1.2
1.5
1.6
1.8
46810.The de-Broglie wavelength associated with proton changes by 0.25% if its momentum is
changed by $p_0$. The initial momentum was
changed by $p_0$. The initial momentum was
100 $p_0$
$p_0$/400
401 $p_0$
$p_0$/100
46811.A closed cubical box is completely filled with water and is accelerated horizontally towards
right with constant acceleration a. The resultant normal force by the water on the top of the box
right with constant acceleration a. The resultant normal force by the water on the top of the box
passes through the centre of the top
passes through a point to the left of the centre
passes through a point to the right of the centre
is zero
46812.Assertion : The nature of X-ray spectrum is continuous.
Reason : X-rays arise due to jumps of electrons from higher orbit to one of the inner orbit in an atom.
A. Both, Assertion and Reason are true and the Reason is correct explanation of the Assertion.
B. Both, Assertion and Reason are true but the Reason is not correct explanation of the Assertion.
C. Assertion is true but the Reason is false.
D. Both, Assertion and Reason are false.
Reason : X-rays arise due to jumps of electrons from higher orbit to one of the inner orbit in an atom.
A. Both, Assertion and Reason are true and the Reason is correct explanation of the Assertion.
B. Both, Assertion and Reason are true but the Reason is not correct explanation of the Assertion.
C. Assertion is true but the Reason is false.
D. Both, Assertion and Reason are false.
A
B
C
D
46813.The moment of inertia of a sphere of mass M and radius R about an axis passing through its
centre is $\\dfrac{2}{5} MR^2$. The radius of gyration of the sphere about a parallel axis to the above and tangent to the sphere is:
centre is $\\dfrac{2}{5} MR^2$. The radius of gyration of the sphere about a parallel axis to the above and tangent to the sphere is:
$\dfrac{7}{5}R$
$\dfrac{3}{5}R$
$(\sqrt{\dfrac{7}{5}})R$
$(\sqrt{\dfrac{3}{5}})R$
46814.A gas mixture consists of 2 moles of O2 and 4 moles of Ar at temperature T. Neglecting all
vibrational modes, the total internal energy of the system is
vibrational modes, the total internal energy of the system is
4RT
15RT
9RT
11RT
46815.A body of mass 6 kg is acted upon by a force which causes a displacement in it given
by x=$\\dfrac{t^2}{2}$ metre, where t is the time in second. The work done by the force in 2 seconds is
by x=$\\dfrac{t^2}{2}$ metre, where t is the time in second. The work done by the force in 2 seconds is
12 J
6 J
9 J
3 J
46816.Two rods of same length and area of cross-section and Young s moduli Y, and Y2 are joined
end to end. The equivalent Young s modulus for the composite rod is
end to end. The equivalent Young s modulus for the composite rod is
$\dfrac{Y_1+Y_2}{2}$
$\dfrac{2Y_1Y_2}{Y_1+Y_2}$
$\sqrt{Y_1Y_2}$
$Y_1+Y_2$
46817.If a person can throw a stone to maximum height of h metre vertically, then the
maximum distance through which it can be thrown horizontally by the same person is
maximum distance through which it can be thrown horizontally by the same person is
$\dfrac{h}{2}$
h
2h
3h
46818.A thin copper wire of length l increases in length by 1%, when heated from 0°C to 100°C. If
a thin copper plate of area (2 l * l) is heated from 0°C to 100°C, the percentage increase in its are would be
a thin copper plate of area (2 l * l) is heated from 0°C to 100°C, the percentage increase in its are would be
1%
2%
3%
4%
46819.3 mole of hydrogen is mixed with 1 mole of neon.
The molar specific heat at constant pressure is
The molar specific heat at constant pressure is
$\dfrac{9R}{4}$
$\dfrac{9R}{2}$
$\dfrac{13R}{4}$
$\dfrac{13R}{2}$
46820.3. Two conducting rings P and Q of radii r and 2r moving uniformly in opposite directions with
centre of mass velocities 2v and v respectively on a conducting surface S. There is a uniform field of magnitude B perpendicular to the plane of the rings.
The potential difference between the highest points of the two rings is
centre of mass velocities 2v and v respectively on a conducting surface S. There is a uniform field of magnitude B perpendicular to the plane of the rings.
The potential difference between the highest points of the two rings is
zero
4 Bvr
8 Byr
16 Bvr
46821.In an electromagnetic wave, the magnetic field is given by
$B_y=2*10^{-7}sin(0.5*10^3x+1.5*10^{11}t)T.$
The intensity of e.m. wave is about
$B_y=2*10^{-7}sin(0.5*10^3x+1.5*10^{11}t)T.$
The intensity of e.m. wave is about
2 W $m^{-2}$
5 W $m^{-2}$
6 W $m^{-2}$
10 W $m^{-2}$
46822.A cubical vessel of height 1 m is full of water. What is the amount of work done in
pumping water out of the vessel ? (Take g = 10 m $S^2$)
pumping water out of the vessel ? (Take g = 10 m $S^2$)
1250 J
5000 J
1000 J
2500 J
46823.The resistance across A and B in the figure below will be
3 R
R
$\dfrac{R}{3}$
None of the above.
46824.Using the Gibbs energy changes, AG° = + 63.3 kJ for the following reaction,
Ag2CO3(s) = 2Ag(aq) + CO2-3(aq) the ksp of Ag2CO3 (s) in water at 25°C is (R = 8.314 JK mol!)
Ag2CO3(s) = 2Ag(aq) + CO2-3(aq) the ksp of Ag2CO3 (s) in water at 25°C is (R = 8.314 JK mol!)
$3.2x10^-{26}$
$8.0x10^-{12}$
$2.9x10^-3 $
$7.9x10^-2$
46825.Successive emission of an a-particle and two B-particles by an atom of a radioactive element results in the formation of its:
isobar
isomer
isotone
isotope
46828.Bithional is generally added to the soaps as an additive to function as a/an
buffering agent
antiseptic
softner
dryer