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Sofiya Parihar
Subject: Physics
, asked on 2/2/18
Answer question.no.33
The ground state energy of H-atom is -13.6 eV.
If an electron makes a transition from an energy level - 0.85 eV to - 1.51 eV, calculate the wavelength of the spectral line emitted. To which series of hydrogen spectrum does this wavelength belong?
Answer: 18751A, Paschen series
Answer
2
Sofiya Parihar
Subject: Physics
, asked on 2/2/18
Q.32. Using Bohr's postulates for H -atom, show that the total energy (E) of the electron in the stationary states can be expressed as the sum of kinetic energy (K) and potential energy (U), where K = - 2U. Hence, deduce the expression for the total energy in the
n
th energy level of hydrogen atom.
Answer
1
Guna Shekar
Subject: Physics
, asked on 30/1/18
3 moles of a diatomic ideal gas undergo the process V^3/T^2 = constant. If the temperature is increased by 200K, work done by gas will be?
1) 200R
3) 400R
3) 600R
4) 800R
Answer
1
Guna Shekar
Subject: Physics
, asked on 30/1/18
Q. As shown in figure, two uniform rods each of mass M and length L are joined. Moment of Inertia of system about an axis perpendicular to plane of figure through A is?
Answer
1
Guna Shekar
Subject: Physics
, asked on 30/1/18
Particles A and B of masses m1 and m2 are moving under mutual force only. F on A is applied by B and (-F) on B is applied by A. Acceleration of A relative to B is given by?
Answer
1
Guna Shekar
Subject: Physics
, asked on 30/1/18
The weight of metal sphere when immersed in water at 0
o
C is w1 and that at 50
o
C is w2. If the coefficient of cubical expansion of the metal is less than that of water, then
1) w1=w2
2) w1<w2
3)w1>w2
Answer
1
Guna Shekar
Subject: Physics
, asked on 30/1/18
An electric heater converts ice at 0
o
C in a bucket into water in 10 minutes. The same heater heats the same water to 100
o
C in another 12.5 minutes. The latent heat of ice is(neglect heat capacity of bucket)(Specific heat of water is 1 cal/g
o
C)?
Answer
1
Guna Shekar
Subject: Physics
, asked on 30/1/18
Q.18 A ball collides perfectly inelastically with smooth horizontal ground at angle
30
°
with vertical as shown. Fraction of kinetic energy lost by the ball due to collision is
(1) 1
(2) 0.5
(3) 0.25
(4) 0.75
Answer
1
Guna Shekar
Subject: Physics
, asked on 30/1/18
Please solve
Q.25. Sound produced by a source of wavelength 114 m passes through a tube of given figure. What will be the minimum radius of the loop so that there is no sound detect by the machine placed at the junction B?
(1) 100 m
(2) 50 m
(3) 25 m
(4) 114 m
Answer
1
Guna Shekar
Subject: Physics
, asked on 30/1/18
Please solve:
Q.24. From the figure. the temperature of the junction Q is
(1) 75
°
C
(2) 125
°
C
(3) 85
°
C
(4) 175
°
C
Answer
1
Guna Shekar
Subject: Physics
, asked on 30/1/18
Please solve
Q. Two particles each of mass m are initially at rest and infinitely separate from each other. Due to mutual interaction they move towards each other. Find the kinetic energy of one particle with respect to other when separation between them is d
1
2
Gm
2
d
2
Gm
2
d
3
Gm
2
2
d
4
3
Gm
2
2
d
Answer
1
Guna Shekar
Subject: Physics
, asked on 30/1/18
Please solve
Answer
3
Archana
Subject: Physics
, asked on 26/1/18
Arrange the given elements in increasing order of mass : proton, deutron, alpha particle, electron
Answer
1
Dipesh Malhotra
Subject: Physics
, asked on 10/1/18
Q.Where do we get this formula from?
K
=
1
4
πε
0
.
(
2
e
)
(
Z
e
)
d
=
2
Z
e
2
4
πε
0
d
d
=
2
Z
e
2
4
πε
0
K
Answer
1
Dipesh Malhotra
Subject: Physics
, asked on 10/1/18
How we got this value for KE
Answer
1
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What are you looking for?
The ground state energy of H-atom is -13.6 eV.
If an electron makes a transition from an energy level - 0.85 eV to - 1.51 eV, calculate the wavelength of the spectral line emitted. To which series of hydrogen spectrum does this wavelength belong?
Answer: 18751A, Paschen series
1) 200R
3) 400R
3) 600R
4) 800R
1) w1=w2
2) w1<w2
3)w1>w2
(1) 1
(2) 0.5
(3) 0.25
(4) 0.75
Q.25. Sound produced by a source of wavelength 114 m passes through a tube of given figure. What will be the minimum radius of the loop so that there is no sound detect by the machine placed at the junction B?
(1) 100 m
(2) 50 m
(3) 25 m
(4) 114 m
Q.24. From the figure. the temperature of the junction Q is
(1) 75
(2) 125
(3) 85
(4) 175
Q. Two particles each of mass m are initially at rest and infinitely separate from each other. Due to mutual interaction they move towards each other. Find the kinetic energy of one particle with respect to other when separation between them is d