12583 + Mcqs in Physics Page 208 McqOptions

10351.	The value of the sum of two vectors \[\overrightarrow{A}\] and \[\overrightarrow{B}\] with \[\theta \] as the angle between them is [BHU 1996]
A.	\[\sqrt{{{A}^{2}}+{{B}^{2}}+2AB\cos \theta }\]
B.	\[\sqrt{{{A}^{2}}-{{B}^{2}}+2AB\cos \theta }\]
C.	\[\sqrt{{{A}^{2}}+{{B}^{2}}-2AB\sin \theta }\]
D.	\[\sqrt{{{A}^{2}}+{{B}^{2}}+2AB\sin \theta }\]
Answer» B. \[\sqrt{{{A}^{2}}-{{B}^{2}}+2AB\cos \theta }\]

Discussion

10352.	Assertion : Orbital velocity of a satellite is greater than its escape velocity. Reason : Orbit of a satellite is within the gravitational field of earth whereas escaping is beyond the gravitational field of 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» F.

Discussion

10353.	Assertion : A table cloth can be pulled from a table without dislodging the dishes. Reason : To every action there is an equal and opposite reaction.
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

10354.	Assertion : The focal length of the mirror is f and distance of the object from the focus is u, the magnification of the mirror is f / u. Reason : Magnification \[=\frac{\text{Size of image}}{\text{Size of object}}\] [AIIMS 1994]
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

10355.	Assertion : The fluorescent tube is considered better than an electric bulb. Reason : Efficiency of fluorescent tube is more than the efficiency of electric bulb.
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

10356.	Assertion : If a plane glass slab is placed on the letters of different colours all the letters appear to be raised up to the same height. Reason : Different colours have different wavelengths.
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

10357.	A straight wire of length \[({{\pi }^{2}})\] metre is carrying a current of 2A and the magnetic field due to it is measured at a point distant 1 cm from it. If the wire is to be bent into a circle and is to carry the same current as before, the ratio of the magnetic field at its centre to that obtained in the first case would be [Haryana CEE 1996]
A.	50 : 1
B.	1 : 50
C.	100 : 1
D.	1 : 100
Answer» C. 100 : 1

Discussion

10358.	The distance between the plates of a parallel plate condenser is \[4mm\] and potential difference is\[60\ volts\]. If the distance between the plates is increased to\[12mm\], then
A.	The potential difference of the condenser will become \[180\ volts\]
B.	The P.D. will become \[20\ volts\]
C.	The P.D. will remain unchanged
D.	The charge on condenser will reduce to one third
Answer» B. The P.D. will become \[20\ volts\]

Discussion

10359.	Assertion : Velocity-time graph for an object in uniform motion along a straight path is a straight line parallel to the time axis. Reason : In uniform motion of an object velocity increases as the square of time elapsed.
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

10360.	If a number of sine waves with modulation indices n1, n2, n3 ........ modulate a carrier wave, then total modulation index (n) of the wave is
A.	n1 + n2 .... + 2(n1 + n2.....)
B.	\[\sqrt{{{n}_{1}}-{{n}_{2}}+{{n}_{3}}..........}\]
C.	\[\sqrt{n_{1}^{2}+n_{2}^{2}+n_{3}^{2}.........}\]
D.	None of these
Answer» D. None of these

Discussion

10361.	Assertion : A positive acceleration of a body can be associated with a ?slowing down? of the body. Reason : Acceleration is a vector quantity.
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

10362.	Assertion : The value of acceleration due to gravity does not depend upon mass of the body on which force is applied. Reason : Acceleration due to gravity is a constant quantity.
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

10363.	A lead ball moving with a velocity V strikes a wall and stops. If 50% of its energy is converted into heat, then what will be the increase in temperature (Specific heat of lead is S) [RPMT 1996]
A.	\[\frac{2{{V}^{2}}}{JS}\]
B.	\[\frac{{{V}^{2}}}{4JS}\]
C.	\[\frac{{{V}^{2}}}{J}\]
D.	\[\frac{{{V}^{2}}S}{2J}\]
Answer» C. \[\frac{{{V}^{2}}}{J}\]

Discussion

10364.	Air in a cylinder is suddenly compressed by a piston, which is then maintained at the same position. With the passage of time [NCERT 1971; DPMT 1995; JIPMER 1997; KCET 2000; AIIMS 2000; MH CET 2001]
A.	The pressure decreases
B.	The pressure increases
C.	The pressure remains the same
D.	The pressure may increase or decrease depending upon the nature of the gas
Answer» B. The pressure increases

Discussion

10365.	From a stationary tank of mass 125000 pound a small shell of mass 25 pound is fired with a muzzle velocity of 1000 ft/sec. The tank recoils with a velocity of [NCERT 1973]
A.	0.1 ft/sec
B.	0.2 ft/sec
C.	0.4 ft/sec
D.	0.8 ft/sec
Answer» C. 0.4 ft/sec

Discussion

10366.	If the surface of a liquid is plane, then the angle of contact of the liquid with the walls of container is [MH CET 2004]
A.	Acute angle
B.	Obtuse angle
C.	\[90{}^\circ \]
D.	\[{{0}^{o}}\]
Answer» E.

Discussion

10367.	Ice formed over lakes has
A.	Very high thermal conductivity and helps in further ice formation
B.	Very low conductivity and retards further formation of ice
C.	It permits quick convection and retards further formation of ice
D.	It is very good radiator
Answer» C. It permits quick convection and retards further formation of ice

Discussion

10368.	Which of the following circular rods. (given radius r and length l) each made of the same material as whose ends are maintained at the same temperature will conduct most heat [CBSE PMT 2005]
A.	\[r=2{{r}_{0}};\ l=2{{l}_{0}}\]
B.	\[r=2{{r}_{0}};\ l={{l}_{0}}\]
C.	\[r={{r}_{0}};\ l={{l}_{0}}\]
D.	\[r={{r}_{0}};\ l=2{{l}_{0}}\]
Answer» C. \[r={{r}_{0}};\ l={{l}_{0}}\]

Discussion

10369.	The phase angle between e.m.f. and current in LCR series ac circuit is [MP PMT/PET 1998]
A.	0 to p / 2
B.	p / 4
C.	p / 2
D.	p
Answer» B. p / 4

Discussion

10370.	Two bodies of masses \[{{m}_{1}}\] and \[{{m}_{2}}\] have equal kinetic energies. If \[{{p}_{1}}\] and \[{{p}_{2}}\] are their respective momentum, then ratio \[{{p}_{1}}:{{p}_{2}}\] is equal to [MP PMT 1985; CPMT 1990]
A.	\[{{m}_{1}}:{{m}_{2}}\]
B.	\[{{m}_{2}}:{{m}_{1}}\]
C.	\[\sqrt{{{m}_{1}}}:\sqrt{{{m}_{2}}}\]
D.	\[m_{1}^{2}:m_{2}^{2}\]
Answer» D. \[m_{1}^{2}:m_{2}^{2}\]

Discussion

10371.	Assertion : Bulk modulus of elasticity (K) represents incompressibility of the material. Reason : Bulk modulus of elasticity is proportional to change in pressure.
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

10372.	A step-down transformer is connected to 2400 volts line and 80 amperes of current is found to flow in output load. The ratio of the turns in primary and secondary coil is 20 : 1. If transformer efficiency is 100%, then the current flowing in primary coil will be [MP PMT 1991]
A.	1600 A
B.	20 A
C.	4 A
D.	1.5 A
Answer» D. 1.5 A

Discussion

10373.	Assertion : Amongst alpha, beta and gamma rays, a-particle has maximum penetrating power. Reason : The alpha particle is heavier than beta and gamma rays.
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

10374.	The maximum value of a.c. voltage in a circuit is 707V. Its rms value is [MP PET 2005]
A.	70.7 V
B.	100 V
C.	500 V
D.	707 V
Answer» D. 707 V

Discussion

10375.	In a capillary tube, water rises to 3 mm. The height of water that will rise in another capillary tube having one-third radius of the first is [BHU 2004]
A.	1 mm
B.	3 mm
C.	6 mm
D.	9 mm
Answer» E.

Discussion

10376.	Assertion : If a proton and an electron are placed in the same uniform electric field. They experience different acceleration. Reason : Electric force on a test charge is independent of its mass. [AIIMS 1994]
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

10377.	Assertion : Hot soup tastes better than the cold soup. Reason : Hot soup has high surface tension and it does not spread properly on our tongue.
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

10378.	The chemical equivalent of silver is 108. If the current in a silver voltameter is 2 Amp., the time required to deposit 27 grams of silver will be [MP PMT 2004]
A.	8.57 hrs
B.	6.70 hrs
C.	3.35 hrs
D.	12.50 hrs
Answer» D. 12.50 hrs

Discussion

10379.	Assertion : The velocity of flow of a liquid is smaller when pressure is larger and viceversa. Reason : According to Bernoulli's theorem, for the stream line flow of an ideal liquid, the total energy per unit mass remains constant.
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

10380.	Sound waves in air are [RPET 2000; AFMC 2001]
A.	Transverse
B.	Longitudinal
C.	De-Broglie waves
D.	All the above
Answer» C. De-Broglie waves

Discussion

10381.	Transverse waves can propagate in [CPMT 1984; KCET 2000; RPET 2001]
A.	Liquids
B.	Solids
C.	Gases
D.	None of these
Answer» C. Gases

Discussion

10382.	Assertion : Gravitational field is zero both at centre and infinity. Reason : The dimensions of gravitational field is \[[L{{T}^{-2}}]\].
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

10383.	The power factor of an ac circuit having resistance (R) and inductance (L) connected in series and an angular velocity \[\omega \] is [AIEEE 2002; MP PET 2000]
A.	\[R/\omega L\]
B.	\[R/{{({{R}^{2}}+{{\omega }^{2}}{{L}^{2}})}^{1/2}}\]
C.	\[\omega L/R\]
D.	\[R/{{({{R}^{2}}-{{\omega }^{2}}{{L}^{2}})}^{1/2}}\]
Answer» C. \[\omega L/R\]

Discussion

10384.	When electron beam passes through an electric field, they gain kinetic energy. If the same beam passes through magnetic field, then
A.	Their energy increases
B.	Their momentum increases
C.	Their potential energy increases
D.	Energy and momentum both remains unchanged
Answer» E.

Discussion

10385.	Assertion : A cyclist always bends inwards while negotiating a curve. Reason : By bending, cyclist lowers his centre of 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» D. If the assertion and reason both are false.

Discussion

10386.	Kinetic energy of emitted cathode rays is dependent on [CPMT 1996]
A.	Only voltage
B.	Only work function
C.	Both (a) and (b)
D.	It does not depend upon any physical quantity
Answer» D. It does not depend upon any physical quantity

Discussion

10387.	Assertion : The power of a pump which raises 100 kg of water in 10sec to a height of 100 m is 10 KW. Reason : The practical unit of power is horse power.
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

10388.	Assertion : Melting of solid causes no change in internal energy. Reason : Latent heat is the heat required to melt a unit mass of solid. [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» F.

Discussion

10389.	If rotational velocity of a dynamo armature is doubled, then induced e.m.f. will become [MP PMT 1991; AIIMS 2000]
A.	Half
B.	Two times
C.	Four times
D.	Unchanged
Answer» C. Four times

Discussion

10390.	The electromagnetic waves of frequency 2 MHz to 30 MHz are [Haryana PMT 2003]
A.	In ground wave propagation
B.	In sky wave propagation
C.	In microwave propagation
D.	In satellite communication
Answer» C. In microwave propagation

Discussion

10391.	The capacity of a spherical conductor in MKS system is [MP PMT 2002]
A.	\[\frac{R}{4\pi {{\varepsilon }_{0}}}\]
B.	\[\frac{4\pi {{\varepsilon }_{0}}}{R}\]
C.	\[4\pi {{\varepsilon }_{0}}R\]
D.	\[4\pi {{\varepsilon }_{0}}{{R}^{2}}\]
Answer» D. \[4\pi {{\varepsilon }_{0}}{{R}^{2}}\]

Discussion

10392.	The relative humidity on a day, when partial pressure of water vapour is \[0.012\times {{10}^{5}}\,Pa\] at 12°C is (take vapour pressure of water at this temperature as \[0.016\times {{10}^{5}}\,Pa\]) [AIIMS 1998]
A.	70%
B.	40%
C.	75%
D.	25%
Answer» D. 25%

Discussion

10393.	A spring balance is graduated on sea level. If a body is weighed with this balance at consecutively increasing heights from earth's surface, the weight indicated by the balance [MP PET 1995]
A.	Will go on increasing continuously
B.	Will go on decreasing continuously
C.	Will remain same
D.	Will first increase and then decrease
Answer» C. Will remain same

Discussion

10394.	In general in an alternating current circuit [MP PMT 1994]
A.	The average value of current is zero
B.	The average value of square of the current is zero
C.	Average power dissipation is zero
D.	The phase difference between voltage and current is zero
Answer» B. The average value of square of the current is zero

Discussion

10395.	The number of turns in the primary coil of a transformer is 200 and the number of turns in the secondary coil is 10. If 240 volt AC is applied to the primary, the output from the secondary will be [BHU 1997; JIPMER 2000]
A.	48 V
B.	24 V
C.	12 V
D.	6 V
Answer» D. 6 V

Discussion

10396.	Force of attraction between two point charges \[Q\] and ? Q separated by \[d\,metre\] is \[{{F}_{e}}\]. When these charges are placed on two identical spheres of radius \[R=0.3\,d\] whose centres are \[d\,metre\]apart, the force of attraction between them is [AIIMS 1995]
A.	Greater than \[{{F}_{e}}\]
B.	Equal to \[{{F}_{e}}\]
C.	Less than \[{{F}_{e}}\]
D.	Less than \[{{F}_{e}}\]
Answer» B. Equal to \[{{F}_{e}}\]

Discussion

10397.	The Rydberg constant R for hydrogen is [MP PMT/PET 1998]
A.	\[R=-\left( \frac{1}{4\pi {{\varepsilon }_{0}}} \right).\frac{2{{\pi }^{2}}m{{e}^{2}}}{c{{h}^{2}}}\]
B.	\[R=\left( \frac{1}{4\pi {{\varepsilon }_{0}}} \right).\frac{2{{\pi }^{2}}m{{e}^{4}}}{c{{h}^{2}}}\]
C.	\[R={{\left( \frac{1}{4\pi {{\varepsilon }_{0}}} \right)}^{2}}.\frac{2{{\pi }^{2}}m{{e}^{4}}}{{{c}^{2}}{{h}^{2}}}\]
D.	\[R={{\left( \frac{1}{4\pi {{\varepsilon }_{0}}} \right)}^{2}}.\frac{2{{\pi }^{2}}m{{e}^{4}}}{c{{h}^{3}}}\]
Answer» E.

Discussion

10398.	If it is assumed that the spinning motion of earth increases, then the weight of a body on equator [RPMT 2003]
A.	Decreases
B.	Remains constant
C.	Increases
D.	Becomes more at poles
Answer» B. Remains constant

Discussion

10399.	A bullet moving with a speed of 100 \[m{{s}^{-1}}\]can just penetrate two planks of equal thickness. Then the number of such planks penetrated by the same bullet when the speed is doubled will be [KCET 2004]
A.	4
B.	8
C.	6
D.	10
Answer» C. 6

Discussion

10400.	Assertion : In all conductors, for studying the thermoelectric behaviour or metals, lead is taken as a reference metal. Reason : In lead, the Thomson effect is negative.
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

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

The value of the sum of two vectors \[\overrightarrow{A}\] and \[\overrightarrow{B}\] with \[\theta \] as the angle between them is [BHU 1996]

Assertion : Orbital velocity of a satellite is greater than its escape velocity. Reason : Orbit of a satellite is within the gravitational field of earth whereas escaping is beyond the gravitational field of earth.

Assertion : A table cloth can be pulled from a table without dislodging the dishes. Reason : To every action there is an equal and opposite reaction.

Assertion : The focal length of the mirror is f and distance of the object from the focus is u, the magnification of the mirror is f / u. Reason : Magnification \[=\frac{\text{Size of image}}{\text{Size of object}}\] [AIIMS 1994]

Assertion : The fluorescent tube is considered better than an electric bulb. Reason : Efficiency of fluorescent tube is more than the efficiency of electric bulb.

Assertion : If a plane glass slab is placed on the letters of different colours all the letters appear to be raised up to the same height. Reason : Different colours have different wavelengths.

The distance between the plates of a parallel plate condenser is \[4mm\] and potential difference is\[60\ volts\]. If the distance between the plates is increased to\[12mm\], then

Assertion : Velocity-time graph for an object in uniform motion along a straight path is a straight line parallel to the time axis. Reason : In uniform motion of an object velocity increases as the square of time elapsed.

If a number of sine waves with modulation indices n1, n2, n3 ........ modulate a carrier wave, then total modulation index (n) of the wave is

Assertion : A positive acceleration of a body can be associated with a ?slowing down? of the body. Reason : Acceleration is a vector quantity.

Assertion : The value of acceleration due to gravity does not depend upon mass of the body on which force is applied. Reason : Acceleration due to gravity is a constant quantity.

A lead ball moving with a velocity V strikes a wall and stops. If 50% of its energy is converted into heat, then what will be the increase in temperature (Specific heat of lead is S) [RPMT 1996]

Air in a cylinder is suddenly compressed by a piston, which is then maintained at the same position. With the passage of time [NCERT 1971; DPMT 1995; JIPMER 1997; KCET 2000; AIIMS 2000; MH CET 2001]

From a stationary tank of mass 125000 pound a small shell of mass 25 pound is fired with a muzzle velocity of 1000 ft/sec. The tank recoils with a velocity of [NCERT 1973]

If the surface of a liquid is plane, then the angle of contact of the liquid with the walls of container is [MH CET 2004]

Ice formed over lakes has

Which of the following circular rods. (given radius r and length l) each made of the same material as whose ends are maintained at the same temperature will conduct most heat [CBSE PMT 2005]

The phase angle between e.m.f. and current in LCR series ac circuit is [MP PMT/PET 1998]

Two bodies of masses \[{{m}_{1}}\] and \[{{m}_{2}}\] have equal kinetic energies. If \[{{p}_{1}}\] and \[{{p}_{2}}\] are their respective momentum, then ratio \[{{p}_{1}}:{{p}_{2}}\] is equal to [MP PMT 1985; CPMT 1990]

Assertion : Bulk modulus of elasticity (K) represents incompressibility of the material. Reason : Bulk modulus of elasticity is proportional to change in pressure.

A step-down transformer is connected to 2400 volts line and 80 amperes of current is found to flow in output load. The ratio of the turns in primary and secondary coil is 20 : 1. If transformer efficiency is 100%, then the current flowing in primary coil will be [MP PMT 1991]

Assertion : Amongst alpha, beta and gamma rays, a-particle has maximum penetrating power. Reason : The alpha particle is heavier than beta and gamma rays.

The maximum value of a.c. voltage in a circuit is 707V. Its rms value is [MP PET 2005]

In a capillary tube, water rises to 3 mm. The height of water that will rise in another capillary tube having one-third radius of the first is [BHU 2004]

Assertion : If a proton and an electron are placed in the same uniform electric field. They experience different acceleration. Reason : Electric force on a test charge is independent of its mass. [AIIMS 1994]

Assertion : Hot soup tastes better than the cold soup. Reason : Hot soup has high surface tension and it does not spread properly on our tongue.

The chemical equivalent of silver is 108. If the current in a silver voltameter is 2 Amp., the time required to deposit 27 grams of silver will be [MP PMT 2004]

Assertion : The velocity of flow of a liquid is smaller when pressure is larger and viceversa. Reason : According to Bernoulli's theorem, for the stream line flow of an ideal liquid, the total energy per unit mass remains constant.

Sound waves in air are [RPET 2000; AFMC 2001]

Transverse waves can propagate in [CPMT 1984; KCET 2000; RPET 2001]

Assertion : Gravitational field is zero both at centre and infinity. Reason : The dimensions of gravitational field is \[[L{{T}^{-2}}]\].

The power factor of an ac circuit having resistance (R) and inductance (L) connected in series and an angular velocity \[\omega \] is [AIEEE 2002; MP PET 2000]

When electron beam passes through an electric field, they gain kinetic energy. If the same beam passes through magnetic field, then

Assertion : A cyclist always bends inwards while negotiating a curve. Reason : By bending, cyclist lowers his centre of gravity.

Kinetic energy of emitted cathode rays is dependent on [CPMT 1996]

Assertion : The power of a pump which raises 100 kg of water in 10sec to a height of 100 m is 10 KW. Reason : The practical unit of power is horse power.

Assertion : Melting of solid causes no change in internal energy. Reason : Latent heat is the heat required to melt a unit mass of solid. [AIIMS 1998]

If rotational velocity of a dynamo armature is doubled, then induced e.m.f. will become [MP PMT 1991; AIIMS 2000]

The electromagnetic waves of frequency 2 MHz to 30 MHz are [Haryana PMT 2003]

The capacity of a spherical conductor in MKS system is [MP PMT 2002]

The relative humidity on a day, when partial pressure of water vapour is \[0.012\times {{10}^{5}}\,Pa\] at 12°C is (take vapour pressure of water at this temperature as \[0.016\times {{10}^{5}}\,Pa\]) [AIIMS 1998]

A spring balance is graduated on sea level. If a body is weighed with this balance at consecutively increasing heights from earth's surface, the weight indicated by the balance [MP PET 1995]

In general in an alternating current circuit [MP PMT 1994]

The number of turns in the primary coil of a transformer is 200 and the number of turns in the secondary coil is 10. If 240 volt AC is applied to the primary, the output from the secondary will be [BHU 1997; JIPMER 2000]

Force of attraction between two point charges \[Q\] and ? Q separated by \[d\,metre\] is \[{{F}_{e}}\]. When these charges are placed on two identical spheres of radius \[R=0.3\,d\] whose centres are \[d\,metre\]apart, the force of attraction between them is [AIIMS 1995]

The Rydberg constant R for hydrogen is [MP PMT/PET 1998]

If it is assumed that the spinning motion of earth increases, then the weight of a body on equator [RPMT 2003]

A bullet moving with a speed of 100 \[m{{s}^{-1}}\]can just penetrate two planks of equal thickness. Then the number of such planks penetrated by the same bullet when the speed is doubled will be [KCET 2004]

Assertion : In all conductors, for studying the thermoelectric behaviour or metals, lead is taken as a reference metal. Reason : In lead, the Thomson effect is negative.