KCET SERIES Physics
Nuclei
21 previous year questions.
Volume: 21 Ques
Yield: High
High-Yield Trend
1
2025 1
2020 1
2019 1
2018 1
2017 1
2015 3
2013 1
2012 2
2011 2
2010 2
2008 2
2007 3
1999 Chapter Questions 21 MCQs
01
PYQ 1999
medium
physics ID: kcet-199
Mass of a photon of frequency v is given by
1
2
3
4
02
PYQ 1999
medium
physics ID: kcet-199
Mean life of a radioactive element is one year. Then its half life is (in year)
1
0.5
2
0.8
3
1
4
0.693
03
PYQ 1999
medium
physics ID: kcet-199
The number of atoms in a radioactive sample reduces from 1000 to 100 in two days. Then the number of atoms remaining at the end of four days is
1
25
2
20
3
10
4
50
04
PYQ 2007
medium
physics ID: kcet-200
The volume of a nucleus is directly proportional to .........
1
2
3
4
05
PYQ 2007
medium
physics ID: kcet-200
A radioactive substance contains nuclei and its half life period is days. The number of nuclei present at the end of days is
1
7500
2
8000
3
9000
4
7070
06
PYQ 2008
easy
physics ID: kcet-200
undergoes successive disintegrations with the end product of .The number of and particles emitted are
1
2
3
4
07
PYQ 2008
medium
physics ID: kcet-200
On bombarding by slow neutron, energy is released. If the power output of atomic reactor is , then the rate of fission will be
1
2
3
4
08
PYQ 2010
medium
physics ID: kcet-201
Pick out the correct statement from the following:
1
is not suitable for a fission reaction.
2
For stable nucleus, the specific binding energy is low.
3
Energy released per unit mass of the reactant is less in case of fusion reaction.
4
Packing fraction may be positive or may be negative
09
PYQ 2010
medium
physics ID: kcet-201
When a neutron is disintegrated to give -particle, ............
1
a proton alone is emitted
2
a proton and an antineutrino are emitted
3
a neutrino alone is emitted
4
a proton and neutrino are emitted
10
PYQ 2011
easy
physics ID: kcet-201
1 curie represents
1
disintegrations per second
2
disintegrations per second
3
disintegrations per second
4
disintegration per second
11
PYQ 2011
medium
physics ID: kcet-201
The thermonuclear reaction of hydrogen inside the stars is taking place by a cycle of operations. The particular element which acts as a catalyst is
1
nitrogen
2
oxygen
3
helium
4
Carbon
12
PYQ 2012
medium
physics ID: kcet-201
Mass numbers of the elements and are and respectively. The specific binding energy of them are and respectively. Then, in which of the following reaction/s energy is released ? (a) (b) (c)
1
only in (a)
2
in (b), (c)
3
in (a), (c)
4
in (a), (b) and (c)
13
PYQ 2013
medium
physics ID: kcet-201
Pick out the correct statements from the following: (I) Electron emission during -decay is always accompained by neutrino (II) Nuclear force is charge independent. (III) Fusion is the chief source of stellar energy
1
(I) , (II) are correct
2
(I) , (III) are correct
3
only (I) is correct
4
(II), (III) are correct
14
PYQ 2013
medium
physics ID: kcet-201
and are the two radioactive elements. The mixture of these elements show a total activity of disintegrations/minute. The half life of is day and that of is days.What will be the total activity after days ? Given : The initial number of atoms in and are equal.
1
200 dis/min
2
250 dis/min
3
500 dis/min
4
150 dis/min
15
PYQ 2013
medium
physics ID: kcet-201
A radioactive substance emits beta particles in the first seconds and beta particles in the next seconds. The mean life of the sample is
1
seconds
2
seconds
3
seconds
4
seconds
16
PYQ 2015
medium
physics ID: kcet-201
A nucleus at rest splits into two nuclear parts having radii in the ratio 1:2. Their velocities are in the ratio
1
8:1
2
6:1
3
4:1
4
2:1
17
PYQ 2017
medium
physics ID: kcet-201
In a nuclear reactor the function of the Moderator is to decrease
1
number of neutrons
2
speed of neutrons
3
escape of neutrons
4
temperature of the reactor
18
PYQ 2018
medium
physics ID: kcet-201
The energy equivalent to a substance of mass 1 g is
1
2
3
4
19
PYQ 2019
easy
physics ID: kcet-201
Which one of the following nuclei has shorter mean life?
1
C
2
A
3
Same for all
4
B
20
PYQ 2020
medium
physics ID: kcet-202
A radio-active elements has half-life of years. What is the fraction that will decay in years?
1
0.25
2
0.5
3
0.75
4
0.85
21
PYQ 2025
medium
physics ID: kcet-202
If the radius of the first Bohr orbit is , then the radius of the second Bohr orbit will be
1
2
3
4