12583 + Mcqs in Physics Page 176 McqOptions

8751.	Assertion : A planet moves faster, when it is closer to the sun in its orbit and vice versa. Reason : Orbital velocity in orbital of planet is 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» D. If the assertion and reason both are false.

Discussion

8752.	The correct relation is [RPMT 2002]
A.	\[r=\frac{2T\,\cos \theta }{hdg}\]
B.	\[r=\frac{hdg}{2T\,\cos \theta }\]
C.	\[r=\frac{2T\,dgh}{\cos \theta }\]
D.	\[r=\frac{T\cos \theta }{2hdg}\]
Answer» B. \[r=\frac{hdg}{2T\,\cos \theta }\]

Discussion

8753.	If the kinetic energy of a body increases by 0.1%, the percent increase of its momentum will be [MP PMT 1994]
A.	0.05%
B.	0.1%
C.	1.0%
D.	10%
Answer» B. 0.1%

Discussion

8754.	If the volume of the given mass of a gas is increased four times, the temperature is raised from 27°C to 127°C. The elasticity will become
A.	4 times
B.	1/4 times
C.	3 times
D.	1/3 times
Answer» E.

Discussion

8755.	A rocket has a mass of 100 kg. 90% of this is fuel. It ejects fuel vapours at the rate of 1 kg/sec with a velocity of 500 m/sec relative to the rocket. It is supposed that the rocket is outside the gravitational field. The initial upthrust on the rocket when it just starts moving upwards is [NCERT 1978]
A.	Zero
B.	500 N
C.	1000 N
D.	2000 N
Answer» C. 1000 N

Discussion

8756.	The primary winding of a transformer has 100 turns and its secondary winding has 200 turns. The primary is connected to an ac supply of 120 V and the current flowing in it is 10 A. The voltage and the current in the secondary are [MP PMT 1991; DPMT 2004]
A.	240 V, 5 A
B.	240 V, 10 A
C.	60 V, 20 A
D.	120 V, 20 A
Answer» B. 240 V, 10 A

Discussion

8757.	The internal energy of the gas increases In [MP PMT 1989; RPMT 2001]
A.	Adiabatic expansion
B.	Adiabatic compression
C.	Isothermal expansion
D.	Isothermal compression
Answer» C. Isothermal expansion

Discussion

8758.	If the potential of a capacitor having capacity of 6 mF is increased from 10 V to 20 V, then increase in its energy will be [Pb. PET 2002]
A.	12 ´ 10?6 J
B.	9 ´ 10?4 J
C.	4 ´ 10?6 J
D.	4 ´ 10?9 J
Answer» C. 4 ´ 10?6 J

Discussion

8759.	Assertion : A body subjected to three concurrent forces cannot be in equilibrium. Reason : If large number of concurrent forces acting on the same point, then the point will be in equilibrium, if sum of all the forces is equal to 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» F.

Discussion

8760.	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

8761.	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

8762.	A 40 mF capacitor in a defibrillator is charged to 3000 V. The energy stored in the capacitor is sent through the patient during a pulse of duration 2ms. The power delivered to the patient is [AIIMS 2004]
A.	45 kW
B.	90 kW
C.	180 kW
D.	360 kW
Answer» C. 180 kW

Discussion

8763.	Assertion : In the following circuit emf is 2V and internal resistance of the cell is 1 W and R = 1W, then reading of the voltmeter is 1V. Reason : \[V=E-ir\] where E = 2V, \[i=\frac{2}{2}=1A\] and R = 1 W [AIIMS 1995]
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

8764.	At what depth below the surface of the earth, acceleration due to gravity g will be half its value 1600 km above the surface of the earth [Pb. PMT 2004]
A.	\[4.2\times {{10}^{6}}\,m\]
B.	\[3.19\times {{10}^{6}}\,m\]
C.	\[1.59\times {{10}^{6}}\,m\]
D.	None of these
Answer» B. \[3.19\times {{10}^{6}}\,m\]

Discussion

8765.	If the K.E. of a body is increased by 300%, its momentum will increase by [JIPMER 1978; AFMC 1993; RPET 1999; CBSE PMT 2002]
A.	100%
B.	150%
C.	\[\sqrt{300}%\]
D.	175%
Answer» B. 150%

Discussion

8766.	In an induction coil, the secondary e.m.f. is [KCET 1994]
A.	Zero during break of the circuit
B.	Very high during make of the circuit
C.	Zero during make of the circuit
D.	Very high during break of the circuit
Answer» E.

Discussion

8767.	The coefficients of thermal conductivity of copper, mercury and glass are respectively Kc, Km and Kg such that Kc > Km > Kg. If the same quantity of heat is to flow per second per unit area of each and corresponding temperature gradients are Xc, Xm and Xg, then [MP PMT 1990]
A.	\[{{X}_{c}}={{X}_{m}}={{X}_{g}}\]
B.	\[{{X}_{c}}>{{X}_{m}}>{{X}_{g}}\]
C.	\[{{X}_{c}}<{{X}_{m}}<{{X}_{g}}\]
D.	\[{{X}_{m}}<{{X}_{c}}<{{X}_{g}}\]
Answer» D. \[{{X}_{m}}<{{X}_{c}}<{{X}_{g}}\]

Discussion

8768.	y component of velocity is 20 and x component of velocity is 10. The direction of motion of the body with the horizontal at this instant is [Manipal 2003]
A.	\[{{\tan }^{-1}}(2)\]
B.	\[{{\tan }^{-1}}(1/2)\]
C.	45°
D.	0°
Answer» B. \[{{\tan }^{-1}}(1/2)\]

Discussion

8769.	The electrochemical equivalent of magnesium is \[0.126\,mg/C\]. A current of 5 A is passed in a suitable solution for 1 hour. The mass of magnesium deposited will be [MP PMT 1995]
A.	0.0378 gm
B.	0.227 gm
C.	0.378 gm
D.	2.27 gm
Answer» E.

Discussion

8770.	An uncharged capacitor is connected to a battery. On charging the capacitor [MP PMT 1994; MP PET 1997; KCET 2002]
A.	All the energy supplied is stored in the capacitor
B.	Half the energy supplied is stored in the capacitor
C.	The energy stored depends upon the capacity of the capacitor only
D.	The energy stored depends upon the time for which the capacitor is charged
Answer» C. The energy stored depends upon the capacity of the capacitor only

Discussion

8771.	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

8772.	A spherical condenser has inner and outer spheres of radii \[a\]and \[b\]respectively. The space between the two is filled with air. The difference between the capacities of two condensers formed when outer sphere is earthed and when inner sphere is earthed will be [MP PET 1996]
A.	Zero
B.	\[4\pi {{\varepsilon }_{0}}a\]
C.	\[4\pi {{\varepsilon }_{0}}b\]
D.	\[4\pi {{\varepsilon }_{0}}a\left( \frac{b}{b-a} \right)\]
Answer» D. \[4\pi {{\varepsilon }_{0}}a\left( \frac{b}{b-a} \right)\]

Discussion

8773.	If specific heat of a substance is infinite, it means [AIIMS 1997]
A.	Heat is given out
B.	Heat is taken in
C.	\[Q=m.c.\Delta \theta \] Þ \[c=\frac{Q}{m.\Delta \theta }\]; when \[\Delta \theta =0\Rightarrow c=\infty \]
D.	All of the above
Answer» C. \[Q=m.c.\Delta \theta \] Þ \[c=\frac{Q}{m.\Delta \theta }\]; when \[\Delta \theta =0\Rightarrow c=\infty \]

Discussion

8774.	Assertion : An artificial satellite with a metal surface is moving above the earth in a circular orbit. A current will be induced in satellite if the plane of the orbit is inclined to the plane of the equator. Reason : The current will be induced only when the speed of satellite is more than 8 km/sec.
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

8775.	If the strength of the magnetic field produced 10cm away from a infinitely long straight conductor is \[{{10}^{-5}}\,Weber/{{m}^{2}}\], the value of the current flowing in the conductor will be [MP PET 1996]
A.	5 ampere
B.	10 ampere
C.	500 ampere
D.	1000 ampere
Answer» B. 10 ampere

Discussion

8776.	The shortest wavelength in the Lyman series of hydrogen spectrum is 912 Å corresponding to a photon energy of 13.6 eV. The shortest wavelength in the Balmer series is about [MP PMT 2004]
A.	3648 Å
B.	8208 Å
C.	1228 Å
D.	6566 Å
Answer» B. 8208 Å

Discussion

8777.	Assertion : Satellite is an ideal platform for remote sensing. Reason : Satellite in polar orbit can provide global coverage or continuous coverage of the fixed area in geostationary configuration.
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

8778.	Maximum and minimum magnitudes of the resultant of two vectors of magnitudes P and Q are in the ratio \[3:1.\]Which of the following relations is true
A.	\[P=2Q\]
B.	\[P=Q\]
C.	\[PQ=1\]
D.	None of these
Answer» B. \[P=Q\]

Discussion

8779.	The magnetic induction at a point P which is distant 4 cm from a long current carrying wire is \[{{10}^{-8}}\,Tesla\]. The field of induction at a distance 12 cm from the same current would be [CBSE PMT 1990; DPMT 2001]
A.	\[3.33\times {{10}^{-9}}\,Tesla\]
B.	\[1.11\times {{10}^{-4}}\,Tesla\]
C.	\[3\times {{10}^{-3}}\,Tesla\]
D.	\[9\times {{10}^{-2}}\,Tesla\]
Answer» B. \[1.11\times {{10}^{-4}}\,Tesla\]

Discussion

8780.	Two spheres made of same substance have diameters in the ratio 1 : 2. Their thermal capacities are in the ratio of [JIPMER 1999]
A.	1 : 2
B.	1 : 8
C.	1 : 4
D.	2 : 1
Answer» C. 1 : 4

Discussion

8781.	One kilogram of ice at 0°C is mixed with one kilogram of water at 80°C. The final temperature of the mixture is (Take : specific heat of water\[=4200\,J\,k{{g}^{-1}}\,{{K}^{-1}}\], latent heat of ice \[=336\,kJ\,k{{g}^{-1}})\] [KCET 2002]
A.	40°C
B.	60°C
C.	0°C
D.	50°C
Answer» D. 50°C

Discussion

8782.	Which of the following is constructed on the principle of electromagnetic induction [MP PMT 2002]
A.	Galvanometer
B.	Electric motor
C.	Generator
D.	Voltmeter
Answer» D. Voltmeter

Discussion

8783.	A series ac circuit consist of an inductor and a capacitor. The inductance and capacitance is respectively 1 henry and \[25\mu F.\] If the current is maximum in circuit then angular frequency will be [RPMT 1999]
A.	200
B.	100
C.	50
D.	200/2\[\pi \]
Answer» B. 100

Discussion

8784.	Assertion : Fragments produced in the fission of \[{{U}^{235}}\] are radioactive. Reason : The fragments have abnormally high proton to neutron ratio.
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

8785.	Assertion : Strain is a unitless quantity. Reason : Strain is equivalent to force.
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

8786.	Assertion : A quick collision between two bodies is more violent than slow collision, even when initial and final velocities are identical. Reason : The rate of change of momentum determine that force is small or 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

8787.	If the value of potential in an ac, circuit is 10V, then the peak value of potential is [CPMT 2003]
A.	\[\frac{10}{\sqrt{2}}\]
B.	\[10\sqrt{2}\]
C.	\[20\sqrt{2}\]
D.	\[\frac{20}{\sqrt{2}}\]
Answer» C. \[20\sqrt{2}\]

Discussion

8788.	Assertion : It is essential that all the lines available in the emission spectrum will also be available in the absorption spectrum. Reason : The spectrum of hydrogen atom is only absorption spectrum.
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

8789.	Read the assertion and reason carefully to mark the correct option out of the options given below: Assertion : Inertia is the property by virtue of which the body is unable to change by itself the state of rest only. Reason : The bodies do not change their state unless acted upon by an unbalanced external force.
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

8790.	A current i ampere flows in a circular arc of wire whose radius is R, which subtend an angle \[3\pi /2\] radian at its centre. The magnetic induction B at the centre is
A.	\[\frac{{{\mu }_{0}}i}{R}\]
B.	\[\frac{{{\mu }_{0}}i}{2R}\]
C.	\[\frac{2{{\mu }_{0}}i}{R}\]
D.	\[\frac{3{{\mu }_{0}}i}{8R}\]
Answer» E.

Discussion

8791.	In Bohr?s model, if the atomic radius of the first orbit is \[{{r}_{0}}\], then the radius of the fourth orbit is [CBSE PMT 2000]
A.	\[{{r}_{0}}\]
B.	\[4{{r}_{0}}\]
C.	\[{{r}_{0}}/16\]
D.	\[16{{r}_{0}}\]
Answer» E.

Discussion

8792.	In an adiabatic expansion of a gas initial and final temperatures are\[{{T}_{1}}\] and \[{{T}_{2}}\] respectively, then the change in internal energy of the gas is [MP PET 1997]
A.	\[\frac{R}{\gamma -1}({{T}_{2}}-{{T}_{1}})\]
B.	\[\frac{R}{\gamma -1}({{T}_{1}}-{{T}_{2}})\]
C.	\[R({{T}_{1}}-{{T}_{2}})\]
D.	Zero
Answer» B. \[\frac{R}{\gamma -1}({{T}_{1}}-{{T}_{2}})\]

Discussion

8793.	An electron is accelerated through a p.d. of 45.5 volt. The velocity acquired by it is (in ms-1) [AIIMS 2004]
A.	\[4\times {{10}^{6}}\]
B.	\[4\times {{10}^{4}}\]
C.	\[{{10}^{6}}\]
D.	Zero
Answer» B. \[4\times {{10}^{4}}\]

Discussion

8794.	Two metallic charged spheres whose radii are 20\[cm\] and 10\[cm\] respectively, have each 150\[micro-coulomb\] positive charge. The common potential after they are connected by a conducting wire is [MP PMT 1991]
A.	\[9\times {{10}^{6}}\ volts\]
B.	\[4.5\times {{10}^{6}}\ volts\]
C.	\[1.8\times {{10}^{7}}\ volts\]
D.	\[13.5\times {{10}^{6}}\ volts\]
Answer» B. \[4.5\times {{10}^{6}}\ volts\]

Discussion

8795.	A transformer is employed to reduce 220 V to 11 V. The primary draws a current of 5 A and the secondary 90 A. The efficiency of the transformer is [MP PMT 1992, 2001, 04]
A.	20%
B.	40%
C.	70%
D.	90%
Answer» E.

Discussion

8796.	A uniform cube is subjected to volume compression. If each side is decreased by 1%, then bulk strain is [EAMCET (Engg.) 1995; DPMT 2000]
A.	0.01
B.	0.06
C.	0.02
D.	0.03
Answer» E.

Discussion

8797.	Assertion : If a pendulum is suspended in a lift and lift is falling freely, then its time period becomes infinite. Reason : Free falling body has acceleration equal to 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» B. If both assertion and reason are true but reason is not the correct explanation of the assertion.

Discussion

8798.	The momentum of a system is conserved [CPMT 1982]
A.	Always
B.	Never
C.	In the absence of an external force on the system
D.	None of the above
Answer» D. None of the above

Discussion

8799.	If a shell fired from a cannon, explodes in mid air, then [Pb. PET 2004]
A.	Its total kinetic energy increases
B.	Its total momentum increases
C.	Its total momentum decreases
D.	None of these
Answer» B. Its total momentum increases

Discussion

8800.	The true statement is, on increasing the distance between the plates of a parallel plate condenser
A.	The electric intensity between the plates will decrease
B.	The electric intensity between the plates will increase
C.	The electric intensity between the plates will remain unchanged
D.	The P.D. between the plates will decrease
Answer» D. The P.D. between the plates will decrease

Discussion

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

Assertion : A planet moves faster, when it is closer to the sun in its orbit and vice versa. Reason : Orbital velocity in orbital of planet is constant.

The correct relation is [RPMT 2002]

If the kinetic energy of a body increases by 0.1%, the percent increase of its momentum will be [MP PMT 1994]

If the volume of the given mass of a gas is increased four times, the temperature is raised from 27°C to 127°C. The elasticity will become

The primary winding of a transformer has 100 turns and its secondary winding has 200 turns. The primary is connected to an ac supply of 120 V and the current flowing in it is 10 A. The voltage and the current in the secondary are [MP PMT 1991; DPMT 2004]

The internal energy of the gas increases In [MP PMT 1989; RPMT 2001]

If the potential of a capacitor having capacity of 6 mF is increased from 10 V to 20 V, then increase in its energy will be [Pb. PET 2002]

Assertion : A body subjected to three concurrent forces cannot be in equilibrium. Reason : If large number of concurrent forces acting on the same point, then the point will be in equilibrium, if sum of all the forces is equal to zero.

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]

A 40 mF capacitor in a defibrillator is charged to 3000 V. The energy stored in the capacitor is sent through the patient during a pulse of duration 2ms. The power delivered to the patient is [AIIMS 2004]

Assertion : In the following circuit emf is 2V and internal resistance of the cell is 1 W and R = 1W, then reading of the voltmeter is 1V. Reason : \[V=E-ir\] where E = 2V, \[i=\frac{2}{2}=1A\] and R = 1 W [AIIMS 1995]

At what depth below the surface of the earth, acceleration due to gravity g will be half its value 1600 km above the surface of the earth [Pb. PMT 2004]

If the K.E. of a body is increased by 300%, its momentum will increase by [JIPMER 1978; AFMC 1993; RPET 1999; CBSE PMT 2002]

In an induction coil, the secondary e.m.f. is [KCET 1994]

The coefficients of thermal conductivity of copper, mercury and glass are respectively Kc, Km and Kg such that Kc > Km > Kg. If the same quantity of heat is to flow per second per unit area of each and corresponding temperature gradients are Xc, Xm and Xg, then [MP PMT 1990]

y component of velocity is 20 and x component of velocity is 10. The direction of motion of the body with the horizontal at this instant is [Manipal 2003]

The electrochemical equivalent of magnesium is \[0.126\,mg/C\]. A current of 5 A is passed in a suitable solution for 1 hour. The mass of magnesium deposited will be [MP PMT 1995]

An uncharged capacitor is connected to a battery. On charging the capacitor [MP PMT 1994; MP PET 1997; KCET 2002]

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

A spherical condenser has inner and outer spheres of radii \[a\]and \[b\]respectively. The space between the two is filled with air. The difference between the capacities of two condensers formed when outer sphere is earthed and when inner sphere is earthed will be [MP PET 1996]

If specific heat of a substance is infinite, it means [AIIMS 1997]

If the strength of the magnetic field produced 10cm away from a infinitely long straight conductor is \[{{10}^{-5}}\,Weber/{{m}^{2}}\], the value of the current flowing in the conductor will be [MP PET 1996]

The shortest wavelength in the Lyman series of hydrogen spectrum is 912 Å corresponding to a photon energy of 13.6 eV. The shortest wavelength in the Balmer series is about [MP PMT 2004]

Assertion : Satellite is an ideal platform for remote sensing. Reason : Satellite in polar orbit can provide global coverage or continuous coverage of the fixed area in geostationary configuration.

Maximum and minimum magnitudes of the resultant of two vectors of magnitudes P and Q are in the ratio \[3:1.\]Which of the following relations is true

The magnetic induction at a point P which is distant 4 cm from a long current carrying wire is \[{{10}^{-8}}\,Tesla\]. The field of induction at a distance 12 cm from the same current would be [CBSE PMT 1990; DPMT 2001]

Two spheres made of same substance have diameters in the ratio 1 : 2. Their thermal capacities are in the ratio of [JIPMER 1999]

One kilogram of ice at 0°C is mixed with one kilogram of water at 80°C. The final temperature of the mixture is (Take : specific heat of water\[=4200\,J\,k{{g}^{-1}}\,{{K}^{-1}}\], latent heat of ice \[=336\,kJ\,k{{g}^{-1}})\] [KCET 2002]

Which of the following is constructed on the principle of electromagnetic induction [MP PMT 2002]

A series ac circuit consist of an inductor and a capacitor. The inductance and capacitance is respectively 1 henry and \[25\mu F.\] If the current is maximum in circuit then angular frequency will be [RPMT 1999]

Assertion : Fragments produced in the fission of \[{{U}^{235}}\] are radioactive. Reason : The fragments have abnormally high proton to neutron ratio.

Assertion : Strain is a unitless quantity. Reason : Strain is equivalent to force.

Assertion : A quick collision between two bodies is more violent than slow collision, even when initial and final velocities are identical. Reason : The rate of change of momentum determine that force is small or large.

If the value of potential in an ac, circuit is 10V, then the peak value of potential is [CPMT 2003]

Assertion : It is essential that all the lines available in the emission spectrum will also be available in the absorption spectrum. Reason : The spectrum of hydrogen atom is only absorption spectrum.

A current i ampere flows in a circular arc of wire whose radius is R, which subtend an angle \[3\pi /2\] radian at its centre. The magnetic induction B at the centre is

In Bohr?s model, if the atomic radius of the first orbit is \[{{r}_{0}}\], then the radius of the fourth orbit is [CBSE PMT 2000]

In an adiabatic expansion of a gas initial and final temperatures are\[{{T}_{1}}\] and \[{{T}_{2}}\] respectively, then the change in internal energy of the gas is [MP PET 1997]

An electron is accelerated through a p.d. of 45.5 volt. The velocity acquired by it is (in ms-1) [AIIMS 2004]

Two metallic charged spheres whose radii are 20\[cm\] and 10\[cm\] respectively, have each 150\[micro-coulomb\] positive charge. The common potential after they are connected by a conducting wire is [MP PMT 1991]

A transformer is employed to reduce 220 V to 11 V. The primary draws a current of 5 A and the secondary 90 A. The efficiency of the transformer is [MP PMT 1992, 2001, 04]

A uniform cube is subjected to volume compression. If each side is decreased by 1%, then bulk strain is [EAMCET (Engg.) 1995; DPMT 2000]

Assertion : If a pendulum is suspended in a lift and lift is falling freely, then its time period becomes infinite. Reason : Free falling body has acceleration equal to acceleration due to gravity.

The momentum of a system is conserved [CPMT 1982]

If a shell fired from a cannon, explodes in mid air, then [Pb. PET 2004]

The true statement is, on increasing the distance between the plates of a parallel plate condenser