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Dipesh Malhotra
Subject: Physics
, asked on 10/1/18
How did we get the eq for Vn pls explain
Answer
1
Ashlesha
Subject: Physics
, asked on 9/1/18
how do we find the series of lines emitted to which this wavelength corresponds?? whats the logic??
Q- A 12.5 eV electron beam is used to excite a gaseous hydrogen atom at room temperature. Determine the wavelengths and the corresponding series of the lines emitted.
Answer
1
Aditya Jayaprakash
Subject: Physics
, asked on 8/1/18
18,19
Q18 a.) Consider a hydrogen atom with its electron in the n
th
orbital. An electromagnetic radiation of wavelength 90 nm is used to ionize the atom. If the kinetic energy of the ejected electron is 10.4 eV, then find the value of n. ( hc = 1242 eV nm)
b.) Name the spectral line series of hydrogen atom which lies in the (i) visible region (ii) ultraviolet region
Q19 a) If the total number of neutrons and protons in a nuclear reaction is conserved, then how energy is absorbed or released in the reaction?
b.) Two radioactive nuclei X and Y with half-life periods 1 hour and 2 hours respectively, initially contain equal number of atoms. Compare their ratio of disintegration after 8 hours
Answer
1
Simranpreet Singh
Subject: Physics
, asked on 29/12/17
Q. Answer the following question, which help you understand the difference b/w Thomson's model and Rutherford's model better.
Is the probability Of backward scattering (i.e., scattering Of
α
-particles at angles greater than 90
°
) predicted by Thomson's model much less, about the same, or much greater than that predicted by Rutherford's model?
Explain in detail.
Answer
1
Simranpreet Singh
Subject: Physics
, asked on 28/12/17
forget about "THIS PAGE" and answer the question...strictly, i need no links...!!!! i need no answer from @PintuBiswas....
Answer
1
Ayush Sharma
Subject: Physics
, asked on 10/12/17
Obtain the expression for the wavelength of de Broglie wave assosiated with an electron accelerated from rest through a potential difference V. The two lines A&B shown in graph. Plot the de Broglie wavelength as the function of 1/underroot v for the two particles having the same charge. Which of the two represents the particles of heavier mass
Answer
1
Shubhrajyoti Ghosh
Subject: Physics
, asked on 28/11/17
No links please
16. How does (i) photoelectric current and (ii) kinetic energy of the photoelectrons emitted in a photocell vary if the intensity of the incident radiation is doubled ?
[CBSE '05]
Answer
2
Shubhrajyoti Ghosh
Subject: Physics
, asked on 22/11/17
Kinetic energy of an electron decreases with the increase of distance of its orbit from the nucleus. But the total energy increases. Explain why.
PLEASE DO NOT GIVE ANY LINKS
Dear Expert,
what is why is it said
No???
It is already said in the question that the K.E. decreases in going from a inner shell to outer shell. But it was asked that why the total energy increases? So please answer that question.
Answer
1
Shubhrajyoti Ghosh
Subject: Physics
, asked on 22/11/17
What do you mean by energy levels of a hydrogen atom? (2marks)
Dear Expert,
I know that there is a similar question in MN 'Ask and Answer' Forum. But it is too long and also contains diagram. But the above question carries only 2 marks. So please give a satisfactory answer according to the marks.
Answer
1
Shubhrajyoti Ghosh
Subject: Physics
, asked on 22/11/17
Why can the spectral lines of hydrogen atom not be explained by Rutherford’s atomic model?
[2 marks]
DEAR EXPERT, I KNOW THAT THERE IS A SIMILAR QUESTION IN MN 'ASK AND ANSWER' FORUM. BUT I AM NOT SATISFIED WITH THAT ANSWER. PLEASE GIVE A SATISFACTORY ANSWER.
Answer
1
Shubhrajyoti Ghosh
Subject: Physics
, asked on 22/11/17
Write two advantages of using gold rather than other metals in Rutherford’s alpha particle scattering experiment?
(
Give two points of advantage
)
[2 marks]
DEAR EXPERT, I KNOW THAT THERE IS A SIMILAR QUESTION IN MN 'ASK AND ANSWER' FORUM. BUT I AM NOT SATISFIED WITH THAT ANSWER. PLEASE GIVE THE ANSWER OF THE ABOVE QUESTION POINT-WISE.
Answer
1
Chinmayi
Subject: Physics
, asked on 21/11/17
Do isotopes have exactly same electronic configuration?Why or Why not?
Answer
1
Laieeqa
Subject: Physics
, asked on 13/11/17
The trajectory of an alpha particle can be computed employing Newton's second law of motion and Coulomb's law for electrostatic force of repulsion between the alpha particle and the positively charged nucleus.
Answer
1
Krishna Vamsi
Subject: Physics
, asked on 12/11/17
A heavy wheel of radius 20 cm and weight 10 kg is to be dragged over a step of height 10 cm, by a
horizontal force F applied at the centre of the wheel. The minimum value of F is
a) 20
kgwt
b) 1
kgwt
c)
10
3
k
g
w
t
d)
10
2
k
g
w
t
Answer
1
Krishna Vamsi
Subject: Physics
, asked on 12/11/17
50th question please
Q50. A solid sphere of mass 1.5 kg rolls on a frictionless horizontal surface, its centre of mass moving at a speed of 5 ms–1. Then it rolls up an incline of 30
0
to horizontal. The height attained by the sphere before it stops is (g = 10 ms
–2
)
a) 5 m b) 1.5 m c) 1.75 m d) 3.65 m
Answer
1
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What are you looking for?
Q- A 12.5 eV electron beam is used to excite a gaseous hydrogen atom at room temperature. Determine the wavelengths and the corresponding series of the lines emitted.
Q18 a.) Consider a hydrogen atom with its electron in the nth orbital. An electromagnetic radiation of wavelength 90 nm is used to ionize the atom. If the kinetic energy of the ejected electron is 10.4 eV, then find the value of n. ( hc = 1242 eV nm)
b.) Name the spectral line series of hydrogen atom which lies in the (i) visible region (ii) ultraviolet region
Q19 a) If the total number of neutrons and protons in a nuclear reaction is conserved, then how energy is absorbed or released in the reaction?
b.) Two radioactive nuclei X and Y with half-life periods 1 hour and 2 hours respectively, initially contain equal number of atoms. Compare their ratio of disintegration after 8 hours
forget about "THIS PAGE" and answer the question...strictly, i need no links...!!!! i need no answer from @PintuBiswas....
16. How does (i) photoelectric current and (ii) kinetic energy of the photoelectrons emitted in a photocell vary if the intensity of the incident radiation is doubled ? [CBSE '05]
PLEASE DO NOT GIVE ANY LINKS
Dear Expert,
what is why is it said No??? It is already said in the question that the K.E. decreases in going from a inner shell to outer shell. But it was asked that why the total energy increases? So please answer that question.
Dear Expert,
I know that there is a similar question in MN 'Ask and Answer' Forum. But it is too long and also contains diagram. But the above question carries only 2 marks. So please give a satisfactory answer according to the marks.
DEAR EXPERT, I KNOW THAT THERE IS A SIMILAR QUESTION IN MN 'ASK AND ANSWER' FORUM. BUT I AM NOT SATISFIED WITH THAT ANSWER. PLEASE GIVE A SATISFACTORY ANSWER.
DEAR EXPERT, I KNOW THAT THERE IS A SIMILAR QUESTION IN MN 'ASK AND ANSWER' FORUM. BUT I AM NOT SATISFIED WITH THAT ANSWER. PLEASE GIVE THE ANSWER OF THE ABOVE QUESTION POINT-WISE.
horizontal force F applied at the centre of the wheel. The minimum value of F is
a) 20 kgwt b) 1 kgwt c) d)
Q50. A solid sphere of mass 1.5 kg rolls on a frictionless horizontal surface, its centre of mass moving at a speed of 5 ms–1. Then it rolls up an incline of 300 to horizontal. The height attained by the sphere before it stops is (g = 10 ms–2 )
a) 5 m b) 1.5 m c) 1.75 m d) 3.65 m