1
WB JEE 2021
MCQ (Single Correct Answer)
+1
-0.25
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A 12.5 eV electron beam is used to bombard gaseous hydrogen at ground state. The energy level upto which the hydrogen atoms would be excited is
A
2
B
3
C
4
D
1
2
WB JEE 2021
MCQ (Single Correct Answer)
+1
-0.25
Change Language
Let r, v, E be the radius of orbit, speed of electron and total energy of electron respectively in H-atom. Which of the following quantities according to Bohr theory, is proportional to the quantum number n ?
A
vr
B
rE
C
$${r \over E}$$
D
$${r \over v}$$
3
WB JEE 2020
MCQ (Single Correct Answer)
+1
-0.25
Change Language
If R is the Rydberg constant in cm-1, then hydrogen atom does not emit any radiation of wavelength in the range of
A
$${1 \over R}$$ to $${4 \over {3R}}$$ cm
B
$${7 \over 5R}$$ to $${19 \over {5R}}$$ cm
C
$${4 \over R}$$ to $${36 \over {5R}}$$ cm
D
$${9 \over R}$$ to $${144 \over {7R}}$$ cm
4
WB JEE 2020
MCQ (Single Correct Answer)
+1
-0.25
Change Language
A nucleus X emits a $$\beta $$-particle to produce a nucleus Y. If their atomic masses are Mx and My respectively, then the maximum energy of the $$\beta $$-particle emitted is (where, me is the mass of an electron and c is the velocity of light)
A
$$({M_x} - {M_y} - {m_e}){c^2}$$
B
$$({M_x} - {M_y} + {m_e}){c^2}$$
C
$$({M_x} - {M_y} ){c^2}$$
D
$$({M_x} - {M_y} - {2m_e}){c^2}$$
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