1
AIPMT 2008
MCQ (Single Correct Answer)
+4
-1
Out of Syllabus
Two radioactive materials X1 and X2 have decay constants $$5\lambda $$ and $$\lambda $$ respectively. If initially they have the same number of nuclei, then the ratio of the number of nuclei of X1 to that X2 will be 1/e after a time
A
1/4$$\lambda $$
B
e/$$\lambda $$
C
$$\lambda $$
D
$${1 \over 2}\lambda $$
2
AIPMT 2008
MCQ (Single Correct Answer)
+4
-1
The ground state energy of hydrogen atom is $$-$$ 13.6 eV. When its electron is in the first excited state, its excitation energy is
A
10.2 eV
B
0
C
3.4 eV
D
6.8 eV
3
AIPMT 2008
MCQ (Single Correct Answer)
+4
-1
If M(A; Z), Mp and Mn denote the masses of the nucleus $${}_Z^AX,$$ proton and neutron respectively in units of u (1 u = 931.5 MeV/c2) and BE represents its bonding energy in MeV, then
A
M(A, Z) = ZMp + (A $$-$$ Z)Mn $$-$$ BE
B
M(A, Z) = ZMp + (A $$-$$ Z)Mn + BE/c2
C
M(A, Z) = ZMp + (A $$-$$ Z)Mn $$-$$ BE/c2
D
M(A, Z) = ZMp + (A $$-$$ Z)Mn + BE
4
AIPMT 2007
MCQ (Single Correct Answer)
+4
-1
The total energy of electron in the ground state of hydrogen atom is $$-$$ 13.6 eV. The kinetic energy of an electron in the first excited state is
A
6.8 eV
B
13.6 eV
C
1.7 eV
D
3.4 eV.
NEET Subjects
EXAM MAP