1. A particle moves in a straight line with retardation proportional to its displacement. Its loss of kinetic energy for any displacement x is proportional to
(a) x2
(b) ex
(c) x
(d) loge x
2. Which of the following statements is false for a particle moving in a circle with a constant angular speed.
(a) The velocity vector is tangent to the circle
(b) the acceleration vector is tangent to the circle
(c) the acceleration vector points to the centre of the circle
(d) the velocity and acceleration vectors are perpandicular to each other
3. If A × B = B × A, then angle between both the vectors is
(a) π
(b) π/3
(c) π/2
(d) π/4
4. A ball is released from top of the tower of hight h m. It takes t sec. to reach the ground. What is the position of ball in T/3 sec.
(a) h/9 m from the ground
(b) 7h/9 m from the ground
(c) 8h/9 m from the ground
(d) 17h/18 m from the ground
5. A machine gun fires a bullet of mass 40g with a velocity 1200 m/s. the man holding it can exert a maximum force 144 N on the gun. How many bullets can he fire per second at the most.
(a) one
(b) four
(c) two
(d) three
Answer
1. a
2. b
3. a
4. c
5. d
Qiestion 1
If relatibe permeability of iron is 5500 then its magnetic susceptibility is
(a) 5500 x 107
(b) 5501
(c) 5499
(d) 5500 x 10-7
Question 2
An atom is paramagnetic if it has
(a) an electric dipole moment
(b) no magnetic moment
(c) a magnetic moment
(d) no electric dipole moment
Question 3
Magnetic moment of a diamegnetic atim is
(a) 0
(b) infinity
(c) negative
(d) positive
Question 4
Mark the correct statement(s)
(a) When a particle moves under uniform circular motion its acceleration is constant
(b) Under the influence of uniform circular motion , instantaneous acceleration is perpandicular to the tangential velocity
(c) Under the influence of non-uniform circular motion , instantaneous acceleration is perpandicular to the tangential velocity
(d) All the above
Qiestion 5
In a meter bridge apparatus , the bridge wire should have
(a) high resistivity and low temperature coefficent
(b) high resistivity and high temperature coefficent
(c) low resistivity and high temperature coefficent
(d) low resistivity and low temperature coefficent
Question 6
Mark out the correct statement
(a) Image formed by convex mirror can be real
(b) Image formed by convex mirror can be virtual
(c) Image formed by convex mirror can be magnified
(d) Image formed by convex mirror can be inverted
Answer
1. c
2. c
3. a
4. b .... When a particle moves under the influence of uniform circular motion magnitude of acceleration is always constant but direction of acceleration keeps changing, it always remains towards the centre . So acceleration is always perpandicular to the the tangential velocity in this case.
5. a
6. a,b,c,d
Given below are the questions you can prepare for IITJEE-2011, AIEEE-2011 and PMT-2011 examinations. Few questions from the questions given below have been aske in previous year IITJEE, AIEEE and other such exams.
Question 1. Three capacitors of 8μF , 12μF and 24μF are connected (A) in series combination and then (B) in parallel combination . The ratio of equivalent capacitance in case (B) to that of case (A) is
(a) 11:1
(b) 1:11
(c) 1:1
(d) 3:1
Question 2. A piece of copper and a piece of germanium are cooled from the room temperature down to 80K
(a) resistance of each of them increases
(b) resistance of each of them decreases
(c) resistance of copper increases and that of germanium drcresaes.
(d) resistance of copper decreases and that of germanium increases.
Question 3. A current flows along the length of infinitely -long straight , thin walled pipe then,
(a) magnetic field at all points inside the pipe is same , but non zero
(b) the magnetic field at any point inside the pipe is zero.
(c) magnetic field is zero only on the axis of the pipe
(d) magnetic field is different at different points inside the pipe
Question 4. The line on the earth's surface joining the points where the field is horizontal is called
(a) magnetic maredian
(b) magnetic axis
(c) isogonic line
(d) magnetic equator
Question 5. The principle used in the transmission of signal through an optical fibre is
(a) total internal reflection
(b) reflection
(c) refraction
(d) dispersion
Question 6. Milikan's oil drop experiment established that
(a) electric charge depends on velocity
(b) electron has wave nature
(c) electron has particle nature
(d) electronic charge is quantized
Question 7. For steady direct current to flow in a circuit
(a) circuit must contain a source of emf
(b) charge distribution in circuit must remain unchanged
(c) lines of current density vector are closed one
(d) all of the above
I hope that these question answes will help you prepare physics for IITJEE, AIEEE and PMT exams
Answer:-
1. (a)
2. (d)
3. (b)
4. (d)
5. (a)
6. (d)
7. (d)
Question 1:A gas is contained in a vertical, frictionless piston cylinder device. The piston has a mass of 20 kg with a cross-sectional area of 20 cm2 and is pulled with a force of 100N. If the atmospheric pressure is 100 kPa, determine the pressure inside.
Question 2:A piston-cylinder device has a ring to limit the expansion stroke. Initially the mass of Oxygen is 2 kg at 500 kPa, 30° C. Heat is now transferred until the piston touches the stop, at which point the volume is twice the original volume. More heat is transferred until the pressure inside also doubles. Determine the amount of heat transfer and the final temperature.
Question 3: A piston cylinder device contains 1 kg of oxygen at 150 kPa, 30°C. The cross-sectional area of the piston is 0.1 m2. Heat is now added causing gas to expand. When the volume reaches 0.2 m3, the piston reaches a linear spring with a spring constant of 120 kN/m. More heat is added until the piston rises another 25 cm. Determine the final pressure, temperature and the energy transfers.
Question 4:Is the energy of the system U an intensive or extensive variable?
Question 5:Suppose we have M+N systems prepared, and the first is in thermal equilibrium with the second, the second in thermal equilibrium with the third, etc., until system M+N- 1 is in thermal equilibrium with the M+Nth system. Is the first system in thermal equilibrium with the M+Nth?
Question 6:A gas is contained in a cylinder with a moveable piston on which a heavy block is placed. Suppose the region outside the chamber is evacuated and the total mass of the block and the movable piston is 102 kg. When 2140 J of heat flows into the gas, the internal energy of the gas increases by 1580 J. What is the distance s through which the piston rises?
Question 7:A resistance thermometer is such that resistance varies with temperature as
RT=R0(1+aT+bT5)
where T represent Temperature on Celsius scale And a,b,R0 are constants.R0 unit is ohm
Based on above data ,Find out the unit of a,b
Solution 1:
Total forces on the piston
Weight of the piston acting downward=200N
Force due to Atmospheric pressure downward =100*103*20*10-4 N=200N
Let P be the Pressure of the gas
Then Force acting due to pressure of gas on the piston upward=PA
Force with the piston is being pulled upward=100N
Total Upward force=Total Downward force
PA + 100=200 +200
20*10-4*P=300
P=150kPa
Solution 2:
Since O2 is a diaatomic gas
CP=7R/2,CV=5R/2
Molecular mass=32 gm
Intial state
Intial volume of gas
V=nRT/P
n=2*103/32
T=303K
R=8.3
P=500*103 N/m2
so V=.314 m3
Second state when At top volume becomes double
Volume=2*.314 =.628m3
Pressure=500*103 N/m2 remains same
So as per ideal gas equation
T=606K
Workdone by the gas=PV=500*103*.314=157*103 J
Heat transfered=nCP(T2 -T1)
=2*103 *7*8.3*303/32*2
=550*103 J
Third state when Pressure becomes double
P=1000*103 N/m2
V=.628m3
As per ideal gas equation
Temperature=1212K
Heat transfered=nCV(T3 -T2)
=2*103 *5*8.3*606/32*2
=785 kJ
So total heat tranfered=550+785=1335 kJ
Final Temperature=1216 K
Solution 3:
Since O2 is a diaatomic gas
CP=7R/2,CV=5R/2
Molecular mass=32 gm
Intial state
Intial volume of gas
V=nRT/P
n=1*103/32
T=303K
R=8.3
P0=500*103 N/m2
so V=.157 m3
Second state ( when piston reaches the spring)
v=.2 m3
P=500*103 N/m2
As per ideal gas equation
Temperature becomes=385.5 K
So heat tranfer till that point=nCP(T2 -T1)
=1*103 *7*8.3*82.5/32*2
=74.8 KJ
Third state ( when it compresses the spring)V=.2+0.1*0.25=0.225 m3
P=500*103 + kx/A
=500*103 + 120*103*25*10-2/.1
=800*103 N/m2
As per ideal equation
Temperature becomes=694K
Change in Internal energy=nCV(T3 -T2)=5nR(T3 -T2)/2
=5*1*103*8.3*308.5/32*2
=200 KJ
Workdone by the gas =P0Ax + kx2/2
=500*103*.1*.25 + 120*103*.25*.25/2
=16.25 KJ
Total heat supplied in this Process=200+16.25=216.25KJ
So net Heat transfer=291.05 KJ
Solution 4:
Doubling the system should double the energy, so U is an extensive variable.
Solution:5
By repeated application of the Zeroth Law, we can state that all M+N systems are in thermal equilibrium with each other.
Solution:6
Total heat supplied =Workdone + Change in internal energy
So work done=2140-1580=560 J
Let s be the distance moved then
the workdone is given by =Fs
Fs=560
s=560/F
=560/102*10
s=.54 m
Solution:7
As per dimension analysis Unit on both sides should be equal
Now since R & R0 both unit are same
Quantity 1+aT+bT5 should be dimension less
so at should be dimension less
so a unit is C-1
similarly bt5 should be dimensionless
so b unit is C-5
(a) x2
(b) ex
(c) x
(d) loge x
2. Which of the following statements is false for a particle moving in a circle with a constant angular speed.
(a) The velocity vector is tangent to the circle
(b) the acceleration vector is tangent to the circle
(c) the acceleration vector points to the centre of the circle
(d) the velocity and acceleration vectors are perpandicular to each other
3. If A × B = B × A, then angle between both the vectors is
(a) π
(b) π/3
(c) π/2
(d) π/4
4. A ball is released from top of the tower of hight h m. It takes t sec. to reach the ground. What is the position of ball in T/3 sec.
(a) h/9 m from the ground
(b) 7h/9 m from the ground
(c) 8h/9 m from the ground
(d) 17h/18 m from the ground
5. A machine gun fires a bullet of mass 40g with a velocity 1200 m/s. the man holding it can exert a maximum force 144 N on the gun. How many bullets can he fire per second at the most.
(a) one
(b) four
(c) two
(d) three
Answer
1. a
2. b
3. a
4. c
5. d
Qiestion 1
If relatibe permeability of iron is 5500 then its magnetic susceptibility is
(a) 5500 x 107
(b) 5501
(c) 5499
(d) 5500 x 10-7
Question 2
An atom is paramagnetic if it has
(a) an electric dipole moment
(b) no magnetic moment
(c) a magnetic moment
(d) no electric dipole moment
Question 3
Magnetic moment of a diamegnetic atim is
(a) 0
(b) infinity
(c) negative
(d) positive
Question 4
Mark the correct statement(s)
(a) When a particle moves under uniform circular motion its acceleration is constant
(b) Under the influence of uniform circular motion , instantaneous acceleration is perpandicular to the tangential velocity
(c) Under the influence of non-uniform circular motion , instantaneous acceleration is perpandicular to the tangential velocity
(d) All the above
Qiestion 5
In a meter bridge apparatus , the bridge wire should have
(a) high resistivity and low temperature coefficent
(b) high resistivity and high temperature coefficent
(c) low resistivity and high temperature coefficent
(d) low resistivity and low temperature coefficent
Question 6
Mark out the correct statement
(a) Image formed by convex mirror can be real
(b) Image formed by convex mirror can be virtual
(c) Image formed by convex mirror can be magnified
(d) Image formed by convex mirror can be inverted
Answer
1. c
2. c
3. a
4. b .... When a particle moves under the influence of uniform circular motion magnitude of acceleration is always constant but direction of acceleration keeps changing, it always remains towards the centre . So acceleration is always perpandicular to the the tangential velocity in this case.
5. a
6. a,b,c,d
Given below are the questions you can prepare for IITJEE-2011, AIEEE-2011 and PMT-2011 examinations. Few questions from the questions given below have been aske in previous year IITJEE, AIEEE and other such exams.
Question 1. Three capacitors of 8μF , 12μF and 24μF are connected (A) in series combination and then (B) in parallel combination . The ratio of equivalent capacitance in case (B) to that of case (A) is
(a) 11:1
(b) 1:11
(c) 1:1
(d) 3:1
Question 2. A piece of copper and a piece of germanium are cooled from the room temperature down to 80K
(a) resistance of each of them increases
(b) resistance of each of them decreases
(c) resistance of copper increases and that of germanium drcresaes.
(d) resistance of copper decreases and that of germanium increases.
Question 3. A current flows along the length of infinitely -long straight , thin walled pipe then,
(a) magnetic field at all points inside the pipe is same , but non zero
(b) the magnetic field at any point inside the pipe is zero.
(c) magnetic field is zero only on the axis of the pipe
(d) magnetic field is different at different points inside the pipe
Question 4. The line on the earth's surface joining the points where the field is horizontal is called
(a) magnetic maredian
(b) magnetic axis
(c) isogonic line
(d) magnetic equator
Question 5. The principle used in the transmission of signal through an optical fibre is
(a) total internal reflection
(b) reflection
(c) refraction
(d) dispersion
Question 6. Milikan's oil drop experiment established that
(a) electric charge depends on velocity
(b) electron has wave nature
(c) electron has particle nature
(d) electronic charge is quantized
Question 7. For steady direct current to flow in a circuit
(a) circuit must contain a source of emf
(b) charge distribution in circuit must remain unchanged
(c) lines of current density vector are closed one
(d) all of the above
I hope that these question answes will help you prepare physics for IITJEE, AIEEE and PMT exams
Answer:-
1. (a)
2. (d)
3. (b)
4. (d)
5. (a)
6. (d)
7. (d)
Question 1:A gas is contained in a vertical, frictionless piston cylinder device. The piston has a mass of 20 kg with a cross-sectional area of 20 cm2 and is pulled with a force of 100N. If the atmospheric pressure is 100 kPa, determine the pressure inside.
Question 2:A piston-cylinder device has a ring to limit the expansion stroke. Initially the mass of Oxygen is 2 kg at 500 kPa, 30° C. Heat is now transferred until the piston touches the stop, at which point the volume is twice the original volume. More heat is transferred until the pressure inside also doubles. Determine the amount of heat transfer and the final temperature.
Question 3: A piston cylinder device contains 1 kg of oxygen at 150 kPa, 30°C. The cross-sectional area of the piston is 0.1 m2. Heat is now added causing gas to expand. When the volume reaches 0.2 m3, the piston reaches a linear spring with a spring constant of 120 kN/m. More heat is added until the piston rises another 25 cm. Determine the final pressure, temperature and the energy transfers.
Question 4:Is the energy of the system U an intensive or extensive variable?
Question 5:Suppose we have M+N systems prepared, and the first is in thermal equilibrium with the second, the second in thermal equilibrium with the third, etc., until system M+N- 1 is in thermal equilibrium with the M+Nth system. Is the first system in thermal equilibrium with the M+Nth?
Question 6:A gas is contained in a cylinder with a moveable piston on which a heavy block is placed. Suppose the region outside the chamber is evacuated and the total mass of the block and the movable piston is 102 kg. When 2140 J of heat flows into the gas, the internal energy of the gas increases by 1580 J. What is the distance s through which the piston rises?
Question 7:A resistance thermometer is such that resistance varies with temperature as
RT=R0(1+aT+bT5)
where T represent Temperature on Celsius scale And a,b,R0 are constants.R0 unit is ohm
Based on above data ,Find out the unit of a,b
Solution 1:
Total forces on the piston
Weight of the piston acting downward=200N
Force due to Atmospheric pressure downward =100*103*20*10-4 N=200N
Let P be the Pressure of the gas
Then Force acting due to pressure of gas on the piston upward=PA
Force with the piston is being pulled upward=100N
Total Upward force=Total Downward force
PA + 100=200 +200
20*10-4*P=300
P=150kPa
Solution 2:
Since O2 is a diaatomic gas
CP=7R/2,CV=5R/2
Molecular mass=32 gm
Intial state
Intial volume of gas
V=nRT/P
n=2*103/32
T=303K
R=8.3
P=500*103 N/m2
so V=.314 m3
Second state when At top volume becomes double
Volume=2*.314 =.628m3
Pressure=500*103 N/m2 remains same
So as per ideal gas equation
T=606K
Workdone by the gas=PV=500*103*.314=157*103 J
Heat transfered=nCP(T2 -T1)
=2*103 *7*8.3*303/32*2
=550*103 J
Third state when Pressure becomes double
P=1000*103 N/m2
V=.628m3
As per ideal gas equation
Temperature=1212K
Heat transfered=nCV(T3 -T2)
=2*103 *5*8.3*606/32*2
=785 kJ
So total heat tranfered=550+785=1335 kJ
Final Temperature=1216 K
Solution 3:
Since O2 is a diaatomic gas
CP=7R/2,CV=5R/2
Molecular mass=32 gm
Intial state
Intial volume of gas
V=nRT/P
n=1*103/32
T=303K
R=8.3
P0=500*103 N/m2
so V=.157 m3
Second state ( when piston reaches the spring)
v=.2 m3
P=500*103 N/m2
As per ideal gas equation
Temperature becomes=385.5 K
So heat tranfer till that point=nCP(T2 -T1)
=1*103 *7*8.3*82.5/32*2
=74.8 KJ
Third state ( when it compresses the spring)V=.2+0.1*0.25=0.225 m3
P=500*103 + kx/A
=500*103 + 120*103*25*10-2/.1
=800*103 N/m2
As per ideal equation
Temperature becomes=694K
Change in Internal energy=nCV(T3 -T2)=5nR(T3 -T2)/2
=5*1*103*8.3*308.5/32*2
=200 KJ
Workdone by the gas =P0Ax + kx2/2
=500*103*.1*.25 + 120*103*.25*.25/2
=16.25 KJ
Total heat supplied in this Process=200+16.25=216.25KJ
So net Heat transfer=291.05 KJ
Solution 4:
Doubling the system should double the energy, so U is an extensive variable.
Solution:5
By repeated application of the Zeroth Law, we can state that all M+N systems are in thermal equilibrium with each other.
Solution:6
Total heat supplied =Workdone + Change in internal energy
So work done=2140-1580=560 J
Let s be the distance moved then
the workdone is given by =Fs
Fs=560
s=560/F
=560/102*10
s=.54 m
Solution:7
As per dimension analysis Unit on both sides should be equal
Now since R & R0 both unit are same
Quantity 1+aT+bT5 should be dimension less
so at should be dimension less
so a unit is C-1
similarly bt5 should be dimensionless
so b unit is C-5
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