12583 + Mcqs in Physics Page 211 McqOptions

10501.	A wire carrying current i is shaped as shown. Section AB is a quarter circle of radius r. The magnetic field is directed [KCET 2002]
A.	At an angle \[\pi /4\] to the plane of the paper
B.	Perpendicular to the plane of the paper and directed in to the paper
C.	Along the bisector of the angle ACB towards AB
D.	Along the bisector of the angle ACB away from AB
Answer» C. Along the bisector of the angle ACB towards AB

Discussion

10502.	While a capacitor remains connected to a battery and dielectric slab is applied between the plates, then [KCET 2001]
A.	Potential difference between the plates is changed
B.	Charge flows from the battery to the capacitor
C.	Electric field between the plates increases
D.	Energy store in the capacitor decreases
Answer» C. Electric field between the plates increases

Discussion

10503.	Assertion : Electric field outside the conducting wire which carries a constant current is zero. Reason : Net charge on conducting wire is zero.
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

10504.	Assertion : The crystalline solids have a sharp melting point. Reason : All the bonds between the atoms or molecules of a crystalline solids are equally strong, that they get broken at the same temperature.
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

10505.	What is the angle between \[\overrightarrow{P}\] and the resultant of \[(\overrightarrow{P}+\overrightarrow{Q})\] and \[(\overrightarrow{P}-\overrightarrow{Q})\]
A.	Zero
B.	\[{{\tan }^{-1}}(P/Q)\]
C.	\[{{\tan }^{-1}}(Q/P)\]
D.	\[{{\tan }^{-1}}(P-Q)/(P+Q)\]
Answer» B. \[{{\tan }^{-1}}(P/Q)\]

Discussion

10506.	Assertion : An N-type semiconductor has a large number of electrons but still it is electrically neutral. Reason : An N-type semiconductor is obtained by doping an intrinsic semiconductor with a pentavalent impurity.
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

10507.	Assertion : Silicon is preferred over germanium for making semiconductor devices. Reason : The energy gap for germanium is more than the energy gap of silicon.
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

10508.	Positive rays consists of [RPMT 1996, 2003]
A.	Electrons
B.	Neutrons
C.	Positive ions
D.	Electromagnetic waves
Answer» D. Electromagnetic waves

Discussion

10509.	The thermal conductivity of a material in CGS system is 0.4. In steady state, the rate of flow of heat 10 cal/sec-cm2, then the thermal gradient will be [MP PMT 1989]
A.	\[10{}^\circ C/cm\]
B.	\[12{}^\circ C/cm\]
C.	\[25{}^\circ C/cm\]
D.	\[20{}^\circ C/cm\]
Answer» D. \[20{}^\circ C/cm\]

Discussion

10510.	A current of 1 ampere is passed through a straight wire of length 2.0 metres. The magnetic field at a point in air at a distance of 3 metres from either end of wire and lying on the axis of wire will be [MP PET 1995]
A.	\[\frac{{{\mu }_{0}}}{2\pi }\]
B.	\[\frac{{{\mu }_{0}}}{4\pi }\]
C.	\[\frac{{{\mu }_{0}}}{8\pi }\]
D.	Zero
Answer» E.

Discussion

10511.	Assertion : A metal piece and a non-metal (stone) piece are dropped from the same height near earth?s surface. Both will reach the earth?s surface simultaneously. Reason : There is no effect of earth?s magnetic field on freely falling body.
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

10512.	Tuning fork \[{{F}_{1}}\] has a frequency of 256 Hz and it is observed to produce 6 beats/second with another tuning fork \[{{F}_{2}}\]. When \[{{F}_{2}}\] is loaded with wax, it still produces 6 beats/second with \[{{F}_{1}}\]. The frequency of \[{{F}_{2}}\] before loading was [MP PET 1990]
A.	253 Hz
B.	262 Hz
C.	250 Hz
D.	259 Hz
Answer» C. 250 Hz

Discussion

10513.	Two metal spheres of capacitance \[{{C}_{1}}\] and \[{{C}_{2}}\] carry some charges. They are put in contact and then separated. The final charges \[{{Q}_{1}}\] and \[{{Q}_{2}}\] on them will satisfy [MP PMT 1999]
A.	\[\frac{{{Q}_{1}}}{{{Q}_{2}}}<\frac{{{C}_{1}}}{{{C}_{2}}}\]
B.	\[\frac{{{Q}_{1}}}{{{Q}_{2}}}=\frac{{{C}_{1}}}{{{C}_{2}}}\]
C.	\[\frac{{{Q}_{1}}}{{{Q}_{2}}}>\frac{{{C}_{1}}}{{{C}_{2}}}\]
D.	\[\frac{{{Q}_{1}}}{{{Q}_{2}}}<\frac{{{C}_{2}}}{{{C}_{1}}}\]
Answer» C. \[\frac{{{Q}_{1}}}{{{Q}_{2}}}>\frac{{{C}_{1}}}{{{C}_{2}}}\]

Discussion

10514.	Water waves are [EAMCET 1979; AIIMS 2004]
A.	Longitudinal
B.	Transverse
C.	Both longitudinal and transverse
D.	Neither longitudinal nor transverse
Answer» D. Neither longitudinal nor transverse

Discussion

10515.	It is possible to distinguish between the transverse and longitudinal waves by studying the property of [CPMT 1976; EAMCET 1994]
A.	Interference
B.	Diffraction
C.	Reflection
D.	Polarisation
Answer» E.

Discussion

10516.	Two tuning forks of frequencies 256 and 258 vibrations/sec are sounded together, then time interval between consecutive maxima heard by the observer is [MP PET/PMT 1988]
A.	2 sec
B.	0.5 sec
C.	250 sec
D.	252 sec
Answer» C. 250 sec

Discussion

10517.	A tuning fork gives 5 beats with another tuning fork of frequency 100 Hz. When the first tuning fork is loaded with wax, then the number of beats remains unchanged, then what will be the frequency of the first tuning fork [MP PMT 1985]
A.	95 Hz
B.	100 Hz
C.	105 Hz
D.	110 Hz
Answer» D. 110 Hz

Discussion

10518.	Five balls numbered 1 to 5 are suspended using separate threads. Pairs (1, 2), (2, 4) and (4, 1) show electrostatic attraction, while pair (2, 3) and (4, 5) show repulsion. Therefore ball 1 must be [NCERT 1980; MP PMT 2003]
A.	Positively charged
B.	Negatively charged
C.	Neutral
D.	Made of metal
Answer» D. Made of metal

Discussion

10519.	Two forces \[{{\vec{F}}_{1}}=5\hat{i}+10\hat{j}-20\hat{k}\]and \[{{\vec{F}}_{2}}=10\hat{i}-5\hat{j}-15\hat{k}\] act on a single point. The angle between \[{{\vec{F}}_{1}}\]and \[{{\vec{F}}_{2}}\] is nearly [AMU 1995]
A.	\[\text{3}0{}^\circ \]
B.	\[\text{45}{}^\circ \]
C.	\[\text{6}0{}^\circ \]
D.	\[\text{9}0{}^\circ \]
Answer» C. \[\text{6}0{}^\circ \]

Discussion

10520.	Assertion : The rate of change of total momentum of a many particle system is proportional to the sum of the internal forces of the system. Reason : Internal forces can change the kinetic energy but not the momentum of the system.
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

10521.	Assertion : The magnetic field at the ends of a very long current carrying solenoid is half of that at the center. Reason : If the solenoid is sufficiently long, the field within it is uniform.
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

10522.	Assertion : The frequencies of incident, reflected and refracted beam of monochromatic light incident from one medium to another are same Reason : The incident, reflected and refracted rays are coplanar [EAMCET (Engg.) 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» C. If assertion is true but reason is false.

Discussion

10523.	A coil of 200W resistance and 1.0 H inductance is connected to an ac source of frequency \[200/2\pi \,Hz.\] Phase angle between potential and current will be [MP PMT 2003]
A.	30o
B.	90o
C.	45o
D.	0o
Answer» D. 0o

Discussion

10524.	The surface tension for pure water in a capillary tube experiment is [MH CET 2002]
A.	\[\frac{\rho g}{2hr}\]
B.	\[\frac{2}{hr\rho g}\]
C.	\[\frac{r\rho g}{2h}\]
D.	\[\frac{hr\rho g}{2}\]
Answer» E.

Discussion

10525.	Assertion : Bending a wire does not effect electrical resistance. Reason : Resistance of wire is proportional to resistivity of material.
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

10526.	Assertion : Intensity of X-rays can be controlled by adjusting the filament current and voltage. Reason : The intensity of X-rays does not depend on number of X-ray photons emitted per second from the target.
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

10527.	If nearly \[{{10}^{5}}\]coulomb liberate 1 gm equivalent of aluminium, then the amount of aluminium (equivalent weight 9) deposited through electrolysis in 20 minutes by a current of 50 amp will be [CBSE PMT 1998]
A.	0.6 gm
B.	0.09 gm
C.	5.4 gm
D.	10.8 gm
Answer» D. 10.8 gm

Discussion

10528.	The compressibility of water is \[4\times {{10}^{-5}}\] per unit atmospheric pressure. The decrease in volume of 100 cubic centimeter of water under a pressure of 100 atmosphere will be [MP PMT 1990]
A.	0.4 cc
B.	\[4\times {{10}^{-5}}\,cc\]
C.	0.025 cc
D.	0.004 cc
Answer» B. \[4\times {{10}^{-5}}\,cc\]

Discussion

10529.	A coil having N turns carry a current I as shown in the figure. The magnetic field intensity at point P is [BHU 2003; CPMT 2004]
A.	\[\frac{{{\mu }_{0}}NI{{R}^{2}}}{2{{({{R}^{2}}+{{x}^{2}})}^{3/2}}}\]
B.	\[\frac{{{\mu }_{0}}NI}{2R}\]
C.	\[\frac{{{\mu }_{0}}NI{{R}^{2}}}{{{(R+x)}^{2}}}\]
D.	Zero
Answer» B. \[\frac{{{\mu }_{0}}NI}{2R}\]

Discussion

10530.	Water cannot be made conducting by adding small amount of any of the following except
A.	Sodium chloride
B.	Copper sulphate
C.	Ammonium chloride
D.	Sugar
Answer» E.

Discussion

10531.	In which of the following cases forces may not be required to keep the [AIIMS 1983]
A.	Particle going in a circle
B.	Particle going along a straight line
C.	The momentum of the particle constant
D.	Acceleration of the particle constant
Answer» D. Acceleration of the particle constant

Discussion

10532.	Figure shows the energy levels P, Q, R, S and G of an atom where G is the ground state. A red line in the emission spectrum of the atom can be obtained by an energy level change from Q to S. A blue line can be obtained by following energy level change [MP PMT 1994]
A.	P to Q
B.	Q to R
C.	R to S
D.	R to G
Answer» E.

Discussion

10533.	In the Millikan's experiment, the distance between two horizontal plates is 2.5 cm and the potential difference applied is 250 V. The electric field between the plates will be
A.	900 V/m
B.	10000 V/m
C.	625 V/m
D.	6250 V/m
Answer» C. 625 V/m

Discussion

10534.	In the figure shown there are two semicircles of radii \[{{r}_{1}}\] and \[{{r}_{2}}\] in which a current i is flowing. The magnetic induction at the centre O will be
A.	\[\frac{{{\mu }_{0}}i}{r}({{r}_{1}}+{{r}_{2}})\]
B.	\[\frac{{{\mu }_{0}}i}{4}({{r}_{1}}-{{r}_{2}})\]
C.	\[\frac{{{\mu }_{0}}i}{4}\left( \frac{{{r}_{1}}+{{r}_{2}}}{{{r}_{1}}{{r}_{2}}} \right)\]
D.	\[\frac{{{\mu }_{0}}i}{4}\left( \frac{{{r}_{2}}-{{r}_{1}}}{{{r}_{1}}{{r}_{2}}} \right)\]
Answer» D. \[\frac{{{\mu }_{0}}i}{4}\left( \frac{{{r}_{2}}-{{r}_{1}}}{{{r}_{1}}{{r}_{2}}} \right)\]

Discussion

10535.	Assertion : The resolving power of a telescope is more if the diameter of the objective lens is more. Reason : Objective lens of large diameter collects more light. [AIIMS 2005]
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

10536.	Assertion : The refractive index of a prism depends only on the kind of glass of which it is made of and the colour of light Reason : The refractive index of a prism depends upon the refracting angle of the prism and the angle of minimum deviation [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» D. If the assertion and reason both are false.

Discussion

10537.	The capacity of parallel plate condenser depends on [CPMT 1974; MP PMT 2000; JIPMER 2002]
A.	The type of metal used
B.	The thickness of plates
C.	The potential applied across the plates
D.	The separation between the plates
Answer» E.

Discussion

10538.	Assertion : In a common emitter transistor amplifier the input current is much less than the output current. Reason : The common emitter transistor amplifier has very high input impedance. [AIIMS 2005]
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

10539.	Assertion : The number of electrons in a P-type silicon semiconductor is less than the number of electrons in a pure silicon semiconductor at room temperature. Reason : It is due to law of mass action. [AIIMS 2005]
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

10540.	Assertion : The logic gate NOT can be built using diode. Reason : The output voltage and the input voltage of the diode have 180° phase difference. [AIIMS 2005]
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

10541.	Assertion : A brass disc is just fitted in a hole in a steel plate. The system must be cooled to loosen the disc from the hole. Reason : The coefficient of linear expansion for brass is greater than the coefficient of linear expansion for steel.
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

10542.	Assertion : The speed of satellite always remains constant in an orbit. Reason : The speed of a satellite depends on its path.
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

10543.	Two tuning forks have frequencies 380 and 384 Hz respectively. When they are sounded together, they produce 4 beats. After hearing the maximum sound, how long will it take to hear the minimum sound [MP PMT/PET 1998]
A.	\[\frac{1}{2}\]sec
B.	\[\frac{1}{4}\]sec
C.	\[\frac{1}{8}\]sec
D.	\[\frac{1}{16}\]sec
Answer» D. \[\frac{1}{16}\]sec

Discussion

10544.	Assertion : If a point charge q is placed in front of an infinite grounded conducting plane surface, the point charge will experience a force. Reason : This force is due to the induced charge on the conducting surface which is at zero potential.
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

10545.	Assertion : Acceleration is proportional to the displacement. This condition is not sufficient for motion in simple harmonic. Reason : In simple harmonic motion direction of displacement is also considered.
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

10546.	Assertion : Magnetism is relativistic. Reason : When we move along with the charge so that there is no motion relative to us, we find no magnetic field associated with the charge.
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

10547.	In an adiabatic process, the state of a gas is changed from \[{{P}_{1}},{{V}_{1}},{{T}_{1}},\] to \[{{P}_{2}},{{V}_{2}},{{T}_{2}}\]. Which of the following relation is correct [Orissa JEE 2003]
A.	\[{{T}_{1}}{{V}_{1}}^{\gamma -1}={{T}_{2}}{{V}_{2}}^{\gamma -1}\]
B.	\[{{P}_{1}}{{V}_{1}}^{\gamma -1}={{P}_{2}}{{V}_{2}}^{\gamma -1}\]
C.	\[{{T}_{1}}{{P}_{1}}^{\gamma }={{T}_{2}}{{P}_{2}}^{\gamma }\]
D.	\[{{T}_{1}}{{V}_{1}}^{\gamma }={{T}_{2}}{{V}_{2}}^{\gamma }\]
Answer» B. \[{{P}_{1}}{{V}_{1}}^{\gamma -1}={{P}_{2}}{{V}_{2}}^{\gamma -1}\]

Discussion

10548.	The ratio of specific charge of an \[\alpha \]-particle to that of a proton is [BCECE 2003]
A.	2 : 1
B.	1 : 1
C.	1 : 2
D.	1 : 3
Answer» D. 1 : 3

Discussion

10549.	A resistance of 40 ohm and an inductance of 95.5 millihenry are connected in series in a 50 cycles/second ac circuit. The impedance of this combination is very nearly [MP PET 2000]
A.	30 ohm
B.	40 ohm
C.	50 ohm
D.	60 ohm
Answer» D. 60 ohm

Discussion

10550.	A heat flux of \[4000\ J/s\] is to be passed through a copper rod of length \[10\ cm\] and area of cross-section \[100\ c{{m}^{2}}\]. The thermal conductivity of copper is \[400\ W/m{{\ }^{o}}C\]. The two ends of this rod must be kept at a temperature difference of [MP PMT 1999]
A.	\[{{1}^{o}}C\]
B.	\[{{10}^{o}}C\]
C.	\[{{100}^{o}}C\]
D.	\[{{1000}^{o}}C\]
Answer» D. \[{{1000}^{o}}C\]

Discussion

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

A wire carrying current i is shaped as shown. Section AB is a quarter circle of radius r. The magnetic field is directed [KCET 2002]

While a capacitor remains connected to a battery and dielectric slab is applied between the plates, then [KCET 2001]

Assertion : Electric field outside the conducting wire which carries a constant current is zero. Reason : Net charge on conducting wire is zero.

Assertion : The crystalline solids have a sharp melting point. Reason : All the bonds between the atoms or molecules of a crystalline solids are equally strong, that they get broken at the same temperature.

What is the angle between \[\overrightarrow{P}\] and the resultant of \[(\overrightarrow{P}+\overrightarrow{Q})\] and \[(\overrightarrow{P}-\overrightarrow{Q})\]

Assertion : An N-type semiconductor has a large number of electrons but still it is electrically neutral. Reason : An N-type semiconductor is obtained by doping an intrinsic semiconductor with a pentavalent impurity.

Assertion : Silicon is preferred over germanium for making semiconductor devices. Reason : The energy gap for germanium is more than the energy gap of silicon.

Positive rays consists of [RPMT 1996, 2003]

The thermal conductivity of a material in CGS system is 0.4. In steady state, the rate of flow of heat 10 cal/sec-cm2, then the thermal gradient will be [MP PMT 1989]

A current of 1 ampere is passed through a straight wire of length 2.0 metres. The magnetic field at a point in air at a distance of 3 metres from either end of wire and lying on the axis of wire will be [MP PET 1995]

Assertion : A metal piece and a non-metal (stone) piece are dropped from the same height near earth?s surface. Both will reach the earth?s surface simultaneously. Reason : There is no effect of earth?s magnetic field on freely falling body.

Tuning fork \[{{F}_{1}}\] has a frequency of 256 Hz and it is observed to produce 6 beats/second with another tuning fork \[{{F}_{2}}\]. When \[{{F}_{2}}\] is loaded with wax, it still produces 6 beats/second with \[{{F}_{1}}\]. The frequency of \[{{F}_{2}}\] before loading was [MP PET 1990]

Two metal spheres of capacitance \[{{C}_{1}}\] and \[{{C}_{2}}\] carry some charges. They are put in contact and then separated. The final charges \[{{Q}_{1}}\] and \[{{Q}_{2}}\] on them will satisfy [MP PMT 1999]

Water waves are [EAMCET 1979; AIIMS 2004]

It is possible to distinguish between the transverse and longitudinal waves by studying the property of [CPMT 1976; EAMCET 1994]

Two tuning forks of frequencies 256 and 258 vibrations/sec are sounded together, then time interval between consecutive maxima heard by the observer is [MP PET/PMT 1988]

A tuning fork gives 5 beats with another tuning fork of frequency 100 Hz. When the first tuning fork is loaded with wax, then the number of beats remains unchanged, then what will be the frequency of the first tuning fork [MP PMT 1985]

Five balls numbered 1 to 5 are suspended using separate threads. Pairs (1, 2), (2, 4) and (4, 1) show electrostatic attraction, while pair (2, 3) and (4, 5) show repulsion. Therefore ball 1 must be [NCERT 1980; MP PMT 2003]

Two forces \[{{\vec{F}}_{1}}=5\hat{i}+10\hat{j}-20\hat{k}\]and \[{{\vec{F}}_{2}}=10\hat{i}-5\hat{j}-15\hat{k}\] act on a single point. The angle between \[{{\vec{F}}_{1}}\]and \[{{\vec{F}}_{2}}\] is nearly [AMU 1995]

Assertion : The rate of change of total momentum of a many particle system is proportional to the sum of the internal forces of the system. Reason : Internal forces can change the kinetic energy but not the momentum of the system.

Assertion : The magnetic field at the ends of a very long current carrying solenoid is half of that at the center. Reason : If the solenoid is sufficiently long, the field within it is uniform.

Assertion : The frequencies of incident, reflected and refracted beam of monochromatic light incident from one medium to another are same Reason : The incident, reflected and refracted rays are coplanar [EAMCET (Engg.) 2000]

A coil of 200W resistance and 1.0 H inductance is connected to an ac source of frequency \[200/2\pi \,Hz.\] Phase angle between potential and current will be [MP PMT 2003]

The surface tension for pure water in a capillary tube experiment is [MH CET 2002]

Assertion : Bending a wire does not effect electrical resistance. Reason : Resistance of wire is proportional to resistivity of material.

Assertion : Intensity of X-rays can be controlled by adjusting the filament current and voltage. Reason : The intensity of X-rays does not depend on number of X-ray photons emitted per second from the target.

If nearly \[{{10}^{5}}\]coulomb liberate 1 gm equivalent of aluminium, then the amount of aluminium (equivalent weight 9) deposited through electrolysis in 20 minutes by a current of 50 amp will be [CBSE PMT 1998]

The compressibility of water is \[4\times {{10}^{-5}}\] per unit atmospheric pressure. The decrease in volume of 100 cubic centimeter of water under a pressure of 100 atmosphere will be [MP PMT 1990]

A coil having N turns carry a current I as shown in the figure. The magnetic field intensity at point P is [BHU 2003; CPMT 2004]

Water cannot be made conducting by adding small amount of any of the following except

In which of the following cases forces may not be required to keep the [AIIMS 1983]

Figure shows the energy levels P, Q, R, S and G of an atom where G is the ground state. A red line in the emission spectrum of the atom can be obtained by an energy level change from Q to S. A blue line can be obtained by following energy level change [MP PMT 1994]

In the Millikan's experiment, the distance between two horizontal plates is 2.5 cm and the potential difference applied is 250 V. The electric field between the plates will be

In the figure shown there are two semicircles of radii \[{{r}_{1}}\] and \[{{r}_{2}}\] in which a current i is flowing. The magnetic induction at the centre O will be

Assertion : The resolving power of a telescope is more if the diameter of the objective lens is more. Reason : Objective lens of large diameter collects more light. [AIIMS 2005]

Assertion : The refractive index of a prism depends only on the kind of glass of which it is made of and the colour of light Reason : The refractive index of a prism depends upon the refracting angle of the prism and the angle of minimum deviation [AIIMS 2000]

The capacity of parallel plate condenser depends on [CPMT 1974; MP PMT 2000; JIPMER 2002]

Assertion : In a common emitter transistor amplifier the input current is much less than the output current. Reason : The common emitter transistor amplifier has very high input impedance. [AIIMS 2005]

Assertion : The number of electrons in a P-type silicon semiconductor is less than the number of electrons in a pure silicon semiconductor at room temperature. Reason : It is due to law of mass action. [AIIMS 2005]

Assertion : The logic gate NOT can be built using diode. Reason : The output voltage and the input voltage of the diode have 180° phase difference. [AIIMS 2005]

Assertion : A brass disc is just fitted in a hole in a steel plate. The system must be cooled to loosen the disc from the hole. Reason : The coefficient of linear expansion for brass is greater than the coefficient of linear expansion for steel.

Assertion : The speed of satellite always remains constant in an orbit. Reason : The speed of a satellite depends on its path.

Two tuning forks have frequencies 380 and 384 Hz respectively. When they are sounded together, they produce 4 beats. After hearing the maximum sound, how long will it take to hear the minimum sound [MP PMT/PET 1998]

Assertion : If a point charge q is placed in front of an infinite grounded conducting plane surface, the point charge will experience a force. Reason : This force is due to the induced charge on the conducting surface which is at zero potential.

Assertion : Acceleration is proportional to the displacement. This condition is not sufficient for motion in simple harmonic. Reason : In simple harmonic motion direction of displacement is also considered.

Assertion : Magnetism is relativistic. Reason : When we move along with the charge so that there is no motion relative to us, we find no magnetic field associated with the charge.

In an adiabatic process, the state of a gas is changed from \[{{P}_{1}},{{V}_{1}},{{T}_{1}},\] to \[{{P}_{2}},{{V}_{2}},{{T}_{2}}\]. Which of the following relation is correct [Orissa JEE 2003]

The ratio of specific charge of an \[\alpha \]-particle to that of a proton is [BCECE 2003]

A resistance of 40 ohm and an inductance of 95.5 millihenry are connected in series in a 50 cycles/second ac circuit. The impedance of this combination is very nearly [MP PET 2000]

A heat flux of \[4000\ J/s\] is to be passed through a copper rod of length \[10\ cm\] and area of cross-section \[100\ c{{m}^{2}}\]. The thermal conductivity of copper is \[400\ W/m{{\ }^{o}}C\]. The two ends of this rod must be kept at a temperature difference of [MP PMT 1999]