12583 + Mcqs in Physics Page 214 McqOptions

10651.	Assertion : The flash of lightening is seen before the sound of thunder is heard. Reason : Speed of sound is greater than speed of light [AIIMS 2002]
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» D. If the assertion and reason both are false.

Discussion

10652.	Assertion : Speed of wave \[=\frac{Wave\ length}{Time\ period}\] Reason : Wavelength is the distance between two nearest particles in phase. [AIIMS 2002]
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» C. If assertion is true but reason is false.

Discussion

10653.	Assertion : Like sound, light can not propagate in vacuum. Reason : Sound is a square wave. It propagates in a medium by a virtue of damping oscillation. [AIIMS 2000]
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» E. If assertion is false but reason is true.

Discussion

10654.	A glass plate is partly dipped vertically in the mercury and the angle of contact is measured. If the plate is inclined, then the angle of contact will
A.	Increase
B.	Remain unchanged
C.	Increase or decrease
D.	Decrease
Answer» C. Increase or decrease

Discussion

10655.	Hydrogen atom excites energy level from fundamental state to n = 3. Number of spectrum lines according to Bohr, is [CPMT 1997]
A.	4
B.	3
C.	1
D.	2
Answer» C. 1

Discussion

10656.	Assertion : Bohr had to postulate that the electrons in stationary orbits around the nucleus do not radiate. Reason : According to classical physics all moving electrons radiate. [AIIMS 2003]
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» C. If assertion is true but reason is false.

Discussion

10657.	Sound waves have the following frequencies that are audible to human beings [CPMT 1975]
A.	5 c/s
B.	27000 c/s
C.	5000 c/s
D.	50,000 c/s
Answer» D. 50,000 c/s

Discussion

10658.	When a sound wave of frequency 300 Hz passes through a medium the maximum displacement of a particle of the medium is 0.1 cm. The maximum velocity of the particle is equal to [MNR 1992; UPSEAT 1998, 2000; RPMT 2002; Pb. PET 2004]
A.	60 p cm/sec
B.	30 p cm/sec
C.	30 cm/sec
D.	60 cm/sec
Answer» B. 30 p cm/sec

Discussion

10659.	The fact that electric charges are integral multiples of the fundamental electronic charge was proved experimentally by [MP PET 1994]
A.	Planck
B.	J.J. Thomson
C.	Einstein
D.	Millikan
Answer» E.

Discussion

10660.	The capacity of a parallel plate condenser is \[5\mu F\]. When a glass plate is placed between the plates of the conductor, its potential becomes \[1/8th\]of the original value. The value of dielectric constant will be [MP PMT 1985]
A.	1.6
B.	5
C.	8
D.	40
Answer» D. 40

Discussion

10661.	A long solenoid has n turns per meter and current I A is flowing through it. The magnetic field at the ends of the solenoid is [MP PMT 2001; MP PET 2002]
A.	\[\frac{{{\mu }_{0}}nI}{2}\]
B.	\[{{\mu }_{0}}nI\]
C.	Zero
D.	\[2{{\mu }_{0}}nI\]
Answer» B. \[{{\mu }_{0}}nI\]

Discussion

10662.	Assertion : The coil is bound over the metallic frame in moving coil galvanometer. Reason : The metallic frame help in making steady deflection without any oscillation.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion.

Discussion

10663.	Assertion : Solids can support both longitudinal and transverse waves but only longitudinal waves can propagate in gases. Reason : For the propagation of transverse waves, medium must also neccessarly have the property of rigidity.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion.

Discussion

10664.	Assertion : The acceleration of a body down a rough inclined plane is greater than the acceleration due to gravity. Reason : The body is able to slide on a inclined plane only when its acceleration is greater than acceleration due to gravity.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» E. If assertion is false but reason is true.

Discussion

10665.	Assertion : The speed of sound in solids is maximum though their density is large. Reason : The coefficient of elasticity of solid is large.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion.

Discussion

10666.	Assertion : Under given conditions of pressure and temperature, sound travels faster in a monoatomic gas than in diatomic gas. Reason : Opposition for wave to travel is more in diatomic gas than monoatomic gas.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» D. If the assertion and reason both are false.

Discussion

10667.	Assertion : A beam of white light gives a spectrum on passing through a hollow prism. Reason : Speed of light outside the prism is different from the speed of light inside the prism.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» E. If assertion is false but reason is true.

Discussion

10668.	Assertion : For the sensitivity of a camera, its aperture should be reduced. Reason : Smaller the aperture, image focussing is also sharp.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» D. If the assertion and reason both are false.

Discussion

10669.	Assertion : By increasing the diameter of the objective of telescope, we can increase its range. Reason : The range of a telescope tells us how far away a star of some standard brightness can be spotted by telescope.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» C. If assertion is true but reason is false.

Discussion

10670.	A capacitor is used to store 24 watt hour of energy at 1200 volt. What should be the capacitance of the capacitor [Kerala (Engg.) 2001]
A.	\[120\,m\,F\]
B.	\[120\,\mu \,F\]
C.	\[24\,\mu \,F\]
D.	\[24\,m\,F\]
Answer» B. \[120\,\mu \,F\]

Discussion

10671.	The maximum peak to peak voltage of an AM wire is 24 mV and the minimum peak to peak voltage is 8 mV. The modulation factor is
A.	10%
B.	20%
C.	25%
D.	50%
Answer» E.

Discussion

10672.	If the ratio of coefficient of thermal conductivity of silver and copper is 10 : 9, then the ratio of the lengths upto which wax will melt in Ingen Hausz experiment will be [DPMT 2001]
A.	6 : 10
B.	\[\sqrt{10}:3\]
C.	100 : 81
D.	81 : 100
Answer» C. 100 : 81

Discussion

10673.	Two identical samples of a gas are allowed to expand (i) isothermally (ii) adiabatically. Work done is [MNR 1998]
A.	More in the isothermal process
B.	More in the adiabatic process
C.	Neither of them
D.	Equal in both processes
Answer» B. More in the adiabatic process

Discussion

10674.	Assertion : In Millikan's experiment for the determination of charge on an electron, oil drops of any size can be used. Reason : Millikan's experiment determine the charge on electron, by simply measuring the terminal velocity.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» F.

Discussion

10675.	Assertion : Steel is more elastic than rubber. Reason : Under given deforming force, steel is deformed less than rubber.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion.

Discussion

10676.	A light and a heavy body have equal kinetic energy. Which one has a greater momentum? [NCERT 1974; CPMT 1997; DPMT 2001]
A.	The light body
B.	The heavy body
C.	Both have equal momentum
D.	It is not possible to say anything without additional information
Answer» C. Both have equal momentum

Discussion

10677.	Two electrons are separated by a distance of 1Å. What is the coulomb force between them [MH CET 2002]
A.	\[2.3\times {{10}^{-8}}\]N
B.	\[4.6\times {{10}^{-8}}\]N
C.	\[1.5\times {{10}^{-8}}\]N
D.	None of these
Answer» B. \[4.6\times {{10}^{-8}}\]N

Discussion

10678.	A parallel plate capacitor having a plate separation of 2 mm is charged by connecting it to a 300 V supply. The energy density is [BHU 2004]
A.	\[0.0\text{1}\,J/{{m}^{\text{3}}}\]
B.	\[0.\text{1}\,J/{{m}^{\text{3}}}\]
C.	\[\text{1}.0\,J/{{m}^{\text{3}}}\]
D.	\[\text{1}0J/{{m}^{\text{3}}}\]
Answer» C. \[\text{1}.0\,J/{{m}^{\text{3}}}\]

Discussion

10679.	Assertion : Electron has higher mobility than hole in a semiconductor. Reason : Mass of electron is less than the mass of hole.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion.

Discussion

10680.	Assertion : The temperature coefficient of resistance is positive for metals and negative for P-type semiconductor. Reason : The effective charge carriers in metals are negatively charged whereas in P-type semiconductor they are positively charged. [AIIMS 1996]
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» C. If assertion is true but reason is false.

Discussion

10681.	Assertion : If the temperature of a semiconductor is increased then it's resistance decreases. Reason : The energy gap between conduction band and valence band is very small [AIIMS 1997]
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion.

Discussion

10682.	A uniform wire is bent in the form of a circle of radius R. A current I enters at A and leaves at C as shown in the figure : If the length ABC is half of the length ADC, the magnetic field at the centre O will be [MP PMT 1997]
A.	Zero
B.	\[\frac{{{\mu }_{0}}I}{2R}\]
C.	\[\frac{{{\mu }_{0}}I}{4R}\]
D.	\[\frac{{{\mu }_{0}}I}{6R}\]
Answer» B. \[\frac{{{\mu }_{0}}I}{2R}\]

Discussion

10683.	Assertion : The maximum horizontal range of projectile is proportional to square of velocity. Reason : The maximum horizontal range of projectile is equal to maximum height attained by projectile.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» D. If the assertion and reason both are false.

Discussion

10684.	Assertion : In an elastic collision of two bodies, the momentum and energy of each body is conserved. Reason : If two bodies stick to each other, after colliding, the collision is said to be perfectly elastic.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» E. If assertion is false but reason is true.

Discussion

10685.	A gas for which \[\gamma =1.5\]is suddenly compressed to\[\frac{1}{4}\]th of the initial volume. Then the ratio of the final to the initial pressure is [EAMCET 2001]
A.	1 : 16
B.	1 : 8
C.	1 : 4
D.	8 : 1
Answer» E.

Discussion

10686.	Which of the following components of a LCR circuit, with ac supply, dissipates energy [DCE 2004]
A.	L
B.	R
C.	C
D.	All of these
Answer» C. C

Discussion

10687.	If an \[8\,\Omega \] resistance and \[6\,\Omega \] reactance are present in an ac series circuit then the impedance of the circuit will be [MP PMT 2003]
A.	20 ohm
B.	5 ohm
C.	10 ohm
D.	\[14\sqrt{2}\] ohm
Answer» D. \[14\sqrt{2}\] ohm

Discussion

10688.	A body executing simple harmonic motion has a maximum acceleration equal to \[24metres/se{{c}^{2}}\] and maximum velocity equal to \[16\ metres/sec\]. The amplitude of the simple harmonic motion is [MP PMT 1995; DPMT 2002; RPET 2003; Pb. PET 2004]
A.	\[\frac{32}{3}metres\]
B.	\[\frac{3}{32}metres\]
C.	\[\frac{1024}{9}metres\]
D.	\[\frac{64}{9}metres\]
Answer» B. \[\frac{3}{32}metres\]

Discussion

10689.	The reactance of a coil when used in the domestic ac power supply (220 volt, 50 cycles) is 100 ohm. The self inductance of the coil is nearly [MP PMT 1996]
A.	3.2 henry
B.	0.32 henry
C.	2.2 henry
D.	0.22 henry
Answer» C. 2.2 henry

Discussion

10690.	A body at rest may have
A.	Energy
B.	Momentum
C.	Speed
D.	Velocity
Answer» B. Momentum

Discussion

10691.	Two capillaries made of same material but of different radii are dipped in a liquid. The rise of liquid in one capillary is 2.2 cm and that in the other is 6.6 cm. The ratio of their radii is [MP PET 1990]
A.	9 : 1
B.	1 : 9
C.	3 : 1
D.	1 : 3
Answer» D. 1 : 3

Discussion

10692.	Which of the following statements are true regarding Bohr's model of hydrogen atom (I) Orbiting speed of electron decreases as it shifts to discrete orbits away from the nucleus (II) Radii of allowed orbits of electron are proportional to the principal quantum number (III) Frequency with which electrons orbits around the nucleus in discrete orbits is inversely proportional to the principal quantum number (IV) Binding force with which the electron is bound to the nucleus increases as it shifts to outer orbits Select correct answer using the codes given below Codes : [SCRA 1998]
A.	I and III
B.	II and IV
C.	I, II and III
D.	II, III and IV
Answer» B. II and IV

Discussion

10693.	Assertion : The film which appears bright in reflected system will appear dark in the transmitted light and vice-versa. Reason : The conditions for film to appear bright or dark in reflected light are just reverse to those in the transmitted light.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion.

Discussion

10694.	Assertion : Newton?s rings are formed in the reflected system. When the space between the lens and the glass plate is filled with a liquid of refractive index greater than that of glass, the central spot of the pattern is dark. Reason : The reflection is Newton?s ring cases will be from a denser to a rarer medium and the two interfering rays are reflected under similar conditions. [AIIMS 1998]
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion.

Discussion

10695.	Assertion : No interference pattern is detected when two coherent sources are infinitely close to each other. Reason : The fringe width is inversely proportional to the distance between the two slits.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» C. If assertion is true but reason is false.

Discussion

10696.	An alternating voltage is connected in series with a resistance R and an inductance L If the potential drop across the resistance is 200 V and across the inductance is 150 V, then the applied voltage is [CPMT 1990]
A.	350 V
B.	250 V
C.	500 V
D.	300 V
Answer» C. 500 V

Discussion

10697.	In which of the following systems will the radius of the first orbit \[(n=1)\] be minimum [Kerala PET 2002; CBSE PMT 2003]
A.	Single ionized helium
B.	Deuterium atom
C.	Hydrogen atom
D.	Doubly ionized lithium
Answer» E.

Discussion

10698.	Assertion : Sine and cosine functions are periodic functions. Reason : Sinusoidal functions repeats it values after a definite interval of time.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» B. If both assertion and reason are true but reason is not the correct explanation of the assertion.

Discussion

10699.	Assertion : When a simple pendulum is made to oscillate on the surface of moon, its time period increases. Reason : Moon is much smaller as compared to earth.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» C. If assertion is true but reason is false.

Discussion

10700.	Assertion : The graph between velocity and displacement for a harmonic oscillator is a parabola. Reason : Velocity does not change uniformly with displacement in harmonic motion.
A.	If both assertion and reason are true and the reason is the correct explanation of the assertion.
B.	If both assertion and reason are true but reason is not the correct explanation of the assertion.
C.	If assertion is true but reason is false.
D.	If the assertion and reason both are false.
E.	If assertion is false but reason is true.
Answer» F.

Discussion

Explore topic-wise MCQs in Joint Entrance Exam - Main (JEE Main).

Assertion : The flash of lightening is seen before the sound of thunder is heard. Reason : Speed of sound is greater than speed of light [AIIMS 2002]

Assertion : Speed of wave \[=\frac{Wave\ length}{Time\ period}\] Reason : Wavelength is the distance between two nearest particles in phase. [AIIMS 2002]

Assertion : Like sound, light can not propagate in vacuum. Reason : Sound is a square wave. It propagates in a medium by a virtue of damping oscillation. [AIIMS 2000]

A glass plate is partly dipped vertically in the mercury and the angle of contact is measured. If the plate is inclined, then the angle of contact will

Hydrogen atom excites energy level from fundamental state to n = 3. Number of spectrum lines according to Bohr, is [CPMT 1997]

Assertion : Bohr had to postulate that the electrons in stationary orbits around the nucleus do not radiate. Reason : According to classical physics all moving electrons radiate. [AIIMS 2003]

Sound waves have the following frequencies that are audible to human beings [CPMT 1975]

When a sound wave of frequency 300 Hz passes through a medium the maximum displacement of a particle of the medium is 0.1 cm. The maximum velocity of the particle is equal to [MNR 1992; UPSEAT 1998, 2000; RPMT 2002; Pb. PET 2004]

The fact that electric charges are integral multiples of the fundamental electronic charge was proved experimentally by [MP PET 1994]

The capacity of a parallel plate condenser is \[5\mu F\]. When a glass plate is placed between the plates of the conductor, its potential becomes \[1/8th\]of the original value. The value of dielectric constant will be [MP PMT 1985]

A long solenoid has n turns per meter and current I A is flowing through it. The magnetic field at the ends of the solenoid is [MP PMT 2001; MP PET 2002]

Assertion : The coil is bound over the metallic frame in moving coil galvanometer. Reason : The metallic frame help in making steady deflection without any oscillation.

Assertion : Solids can support both longitudinal and transverse waves but only longitudinal waves can propagate in gases. Reason : For the propagation of transverse waves, medium must also neccessarly have the property of rigidity.

Assertion : The acceleration of a body down a rough inclined plane is greater than the acceleration due to gravity. Reason : The body is able to slide on a inclined plane only when its acceleration is greater than acceleration due to gravity.

Assertion : The speed of sound in solids is maximum though their density is large. Reason : The coefficient of elasticity of solid is large.

Assertion : Under given conditions of pressure and temperature, sound travels faster in a monoatomic gas than in diatomic gas. Reason : Opposition for wave to travel is more in diatomic gas than monoatomic gas.

Assertion : A beam of white light gives a spectrum on passing through a hollow prism. Reason : Speed of light outside the prism is different from the speed of light inside the prism.

Assertion : For the sensitivity of a camera, its aperture should be reduced. Reason : Smaller the aperture, image focussing is also sharp.

Assertion : By increasing the diameter of the objective of telescope, we can increase its range. Reason : The range of a telescope tells us how far away a star of some standard brightness can be spotted by telescope.

A capacitor is used to store 24 watt hour of energy at 1200 volt. What should be the capacitance of the capacitor [Kerala (Engg.) 2001]

The maximum peak to peak voltage of an AM wire is 24 mV and the minimum peak to peak voltage is 8 mV. The modulation factor is

If the ratio of coefficient of thermal conductivity of silver and copper is 10 : 9, then the ratio of the lengths upto which wax will melt in Ingen Hausz experiment will be [DPMT 2001]

Two identical samples of a gas are allowed to expand (i) isothermally (ii) adiabatically. Work done is [MNR 1998]

Assertion : In Millikan's experiment for the determination of charge on an electron, oil drops of any size can be used. Reason : Millikan's experiment determine the charge on electron, by simply measuring the terminal velocity.

Assertion : Steel is more elastic than rubber. Reason : Under given deforming force, steel is deformed less than rubber.

A light and a heavy body have equal kinetic energy. Which one has a greater momentum? [NCERT 1974; CPMT 1997; DPMT 2001]

Two electrons are separated by a distance of 1Å. What is the coulomb force between them [MH CET 2002]

A parallel plate capacitor having a plate separation of 2 mm is charged by connecting it to a 300 V supply. The energy density is [BHU 2004]

Assertion : Electron has higher mobility than hole in a semiconductor. Reason : Mass of electron is less than the mass of hole.

Assertion : The temperature coefficient of resistance is positive for metals and negative for P-type semiconductor. Reason : The effective charge carriers in metals are negatively charged whereas in P-type semiconductor they are positively charged. [AIIMS 1996]

Assertion : If the temperature of a semiconductor is increased then it's resistance decreases. Reason : The energy gap between conduction band and valence band is very small [AIIMS 1997]

A uniform wire is bent in the form of a circle of radius R. A current I enters at A and leaves at C as shown in the figure : If the length ABC is half of the length ADC, the magnetic field at the centre O will be [MP PMT 1997]

Assertion : The maximum horizontal range of projectile is proportional to square of velocity. Reason : The maximum horizontal range of projectile is equal to maximum height attained by projectile.

Assertion : In an elastic collision of two bodies, the momentum and energy of each body is conserved. Reason : If two bodies stick to each other, after colliding, the collision is said to be perfectly elastic.

A gas for which \[\gamma =1.5\]is suddenly compressed to\[\frac{1}{4}\]th of the initial volume. Then the ratio of the final to the initial pressure is [EAMCET 2001]

Which of the following components of a LCR circuit, with ac supply, dissipates energy [DCE 2004]

If an \[8\,\Omega \] resistance and \[6\,\Omega \] reactance are present in an ac series circuit then the impedance of the circuit will be [MP PMT 2003]

A body executing simple harmonic motion has a maximum acceleration equal to \[24metres/se{{c}^{2}}\] and maximum velocity equal to \[16\ metres/sec\]. The amplitude of the simple harmonic motion is [MP PMT 1995; DPMT 2002; RPET 2003; Pb. PET 2004]

The reactance of a coil when used in the domestic ac power supply (220 volt, 50 cycles) is 100 ohm. The self inductance of the coil is nearly [MP PMT 1996]

A body at rest may have

Two capillaries made of same material but of different radii are dipped in a liquid. The rise of liquid in one capillary is 2.2 cm and that in the other is 6.6 cm. The ratio of their radii is [MP PET 1990]

Assertion : The film which appears bright in reflected system will appear dark in the transmitted light and vice-versa. Reason : The conditions for film to appear bright or dark in reflected light are just reverse to those in the transmitted light.

Assertion : No interference pattern is detected when two coherent sources are infinitely close to each other. Reason : The fringe width is inversely proportional to the distance between the two slits.

An alternating voltage is connected in series with a resistance R and an inductance L If the potential drop across the resistance is 200 V and across the inductance is 150 V, then the applied voltage is [CPMT 1990]

In which of the following systems will the radius of the first orbit \[(n=1)\] be minimum [Kerala PET 2002; CBSE PMT 2003]

Assertion : Sine and cosine functions are periodic functions. Reason : Sinusoidal functions repeats it values after a definite interval of time.

Assertion : When a simple pendulum is made to oscillate on the surface of moon, its time period increases. Reason : Moon is much smaller as compared to earth.

Assertion : The graph between velocity and displacement for a harmonic oscillator is a parabola. Reason : Velocity does not change uniformly with displacement in harmonic motion.