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Chaitanya
Subject: Physics
, asked on 2/5/18
Solve this :
1. Red light, however bright, cannot cause emission of electron from a clean zinc surface. But even weak ultraviolet radiations can do so. Why ?
2. Name the series of hydrogen spectrum lying in the ultraviolet region.
Answer
1
Chinmayi
Subject: Physics
, asked on 28/4/18
Both A and B seem to be the answer .
Please provide the most appropriate one and why?
Q.54.
Select the graph shown above that most correctly represents the relationship between the energy of the photon and its wavelength.
(A) Graph A
(B) Graph B
(C) Graph C
(D) Graph D
(E) Graph E
Answer
2
Lavneesh Rajput
Subject: Physics
, asked on 24/4/18
Solve this:
Q.33. What is the disintegration constant of radon if the number of its atoms diminishes by 18 % in 24 hours
(a) 2.1
$\times {10}^{-3}{s}^{-1}$
(b) 2.1
$\times {10}^{-4}{s}^{-1}$
(c) 2.1
$\times {10}^{-5}{s}^{-1}$
(d) 2.1
$\times {10}^{-6}{s}^{-1}$
Answer
1
Lavneesh Rajput
Subject: Physics
, asked on 24/4/18
Solve this:
Q.21. The figure below shows the plot of
$\frac{PV}{nT}$
versus P for oxygen gas at two different temperatures.
Read the following statements concerning the above curves.
(i) The dotted line corresponds to the ideal gas behaviour
(ii)
${T}_{1}>{T}_{2}$
(iii) the value of
$\frac{PV}{nT}$
at the point where the curves meet on the y-axis is the same for all gases.
Which of the above statements is true
(a) (i) only
(b) (i) and (ii) only
(c) all the above
(d) none of these.
Answer
1
Aparna Sahu
Subject: Physics
, asked on 23/4/18
Q.12. Ratio of nuclear radii of
${}^{135}Csto{}^{40}Ca$
is
(A) 1.40
(B) 1.50
(C) 2.750
(D) 3.375
Answer
1
Aparna Sahu
Subject: Physics
, asked on 18/4/18
Q.33. The wavelength of the first line of Balmer series of hydrogen atom is
$\lambda $
. The wavelength of the same line in doubly ionised lithium will be
(a)
$\frac{\lambda}{2}$
(b)
$\frac{\lambda}{9}$
(c)
$\frac{\lambda}{8}$
(d)
$\frac{\lambda}{27}$
Answer
1
Royel Ghost
Subject: Physics
, asked on 12/4/18
$Theequationofmotionofaprojectileisy=12x-\frac{3}{4}{x}^{2}.Thehorizontalcomponentofvelocityis3m/s.\phantom{\rule{0ex}{0ex}}Whatistherangeoftheprojectile?\phantom{\rule{0ex}{0ex}}\left(A\right)18m\phantom{\rule{0ex}{0ex}}\left(B\right)16m\phantom{\rule{0ex}{0ex}}\left(C\right)12m\phantom{\rule{0ex}{0ex}}\left(D\right)21.6m$
Answer
3
Aparna Sahu
Subject: Physics
, asked on 6/4/18
Solve this..:
12. Consider the nuclear reaction
$\begin{array}{c}234\\ 92\end{array}X\to \begin{array}{c}218\\ 88\end{array}Y.$
The number of
$\alpha and\beta $
particles given out our respectively.
(a) 4,6 (b) 6,4
(c) 4,4 (d) 2,4
Answer
1
Aaryaman Bhardwaj
Subject: Physics
, asked on 2/4/18
how to calculate sin(45/2)?
Answer
1
Aparna Sahu
Subject: Physics
, asked on 19/3/18
Solve this.
Q. If electrons are accelerated from rest through a potential difference of 10 kV, what is the wavelength of the associated electron?
Answer
1
Laieeqa
Subject: Physics
, asked on 7/3/18
Solve this:
Q). If light of wavelength 412.5 nm is incident on each of the metals given below, which ones will show photoelectric emission and why ?
Answer
2
Ketul
Subject: Physics
, asked on 6/3/18
Find the wavelength of electron orbiting in 1st excited stage of hydrogen
Answer
4
Ashwini.. .
Subject: Physics
, asked on 6/3/18
Using bohr's postulate derive the expressionfor the orbital period of the electron moving in nth orbital of hydrogenatom
Answer
1
Ashwini.. .
Subject: Physics
, asked on 6/3/18
Solve this:-
9. Using Bohr's postulates, derive the expression for the orbital period of the electron moving in the n
^{th}
orbit of hydrogen atom.
Answer
1
Abhiram Sankar
Subject: Physics
, asked on 3/3/18
Consider two different hydrogen atoms. The electron in each atom is in an excited state. Is it possible for electrons to have different energy is the same orbital angular momentum according to bohr model? Justify the answer
[NO LINKS PLEASE]
Answer
4
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Next
What are you looking for?

Solve this :1. Red light, however bright, cannot cause emission of electron from a clean zinc surface. But even weak ultraviolet radiations can do so. Why ?

Please provide the most appropriate one and why?

Q.54.

Select the graph shown above that most correctly represents the relationship between the energy of the photon and its wavelength.

(A) Graph A

(B) Graph B

(C) Graph C

(D) Graph D

(E) Graph E

Q.33. What is the disintegration constant of radon if the number of its atoms diminishes by 18 % in 24 hours

(a) 2.1$\times {10}^{-3}{s}^{-1}$

(b) 2.1$\times {10}^{-4}{s}^{-1}$

(c) 2.1$\times {10}^{-5}{s}^{-1}$

(d) 2.1$\times {10}^{-6}{s}^{-1}$

Q.21. The figure below shows the plot of $\frac{PV}{nT}$ versus P for oxygen gas at two different temperatures.

Read the following statements concerning the above curves.

(i) The dotted line corresponds to the ideal gas behaviour

(ii) ${T}_{1}>{T}_{2}$

(iii) the value of $\frac{PV}{nT}$ at the point where the curves meet on the y-axis is the same for all gases.

Which of the above statements is true

(a) (i) only

(b) (i) and (ii) only

(c) all the above

(d) none of these.

(A) 1.40

(B) 1.50

(C) 2.750

(D) 3.375

(a) $\frac{\lambda}{2}$

(b) $\frac{\lambda}{9}$

(c) $\frac{\lambda}{8}$

(d) $\frac{\lambda}{27}$

12. Consider the nuclear reaction $\begin{array}{c}234\\ 92\end{array}X\to \begin{array}{c}218\\ 88\end{array}Y.$ The number of $\alpha and\beta $ particles given out our respectively.

(a) 4,6 (b) 6,4

(c) 4,4 (d) 2,4

Q. If electrons are accelerated from rest through a potential difference of 10 kV, what is the wavelength of the associated electron?

Q). If light of wavelength 412.5 nm is incident on each of the metals given below, which ones will show photoelectric emission and why ?

9. Using Bohr's postulates, derive the expression for the orbital period of the electron moving in the n

^{th}orbit of hydrogen atom.[NO LINKS PLEASE]