50278 + Interview Questions in Physics Page 239 InterviewSolution

11901.	A particle in S.H.M with frequency f. The frequency at which its kinetic energy changes into potential energy is
Answer» A particle in S.H.M with frequency f. The frequency at which its kinetic energy changes into potential energy is

Discussion

11902.	A proton and an α -particle are accelerated through a potential difference of 100 V. The ratio of the wavelength associated with the proton to that associated with an α-particle is
Answer» A proton and an $α$ -particle are accelerated through a potential difference of 100 V. The ratio of the wavelength associated with the proton to that associated with an $α$ -particle is

Discussion

11903.	On the horizontal surface of a truck (µ=0.6),a block of mass 1 kg is placed. If the truck is accelerating at the rate of 5m/sec2 then frictional force on the block will be
Answer» On the horizontal surface of a truck (µ=0.6),a block of mass 1 kg is placed. If the truck is accelerating at the rate of 5m/sec² then frictional force on the block will be

Discussion

11904.	A block of mass 1 kg is placed on a rough wedge which is fixed on an elevator moving upward with constant velocity 2m/s .The block m is at rest wrt wedge .Net reaction force on the block is
Answer» A block of mass 1 kg is placed on a rough wedge which is fixed on an elevator moving upward with constant velocity 2m/s .The block m is at rest wrt wedge .Net reaction force on the block is

Discussion

11905.	AMZ→BM−12Z−1 The number of α and β particles emitted in the above conversion is
Answer» $A_{Z}^{M} \to B_{Z - 1}^{M - 12}$ The number of $α$ and $β$ particles emitted in the above conversion is

Discussion

11906.	The focal lengths of the objective and eye-piece of a telescope are respectively 100 cm and 2 cm. The moon subtends an angle of 0.5∘ at the eye. If it is looked through the telescope, the angle subtended by the moon’s image will be
Answer» The focal lengths of the objective and eye-piece of a telescope are respectively $100 c m$ and $2 c m$ . The moon subtends an angle of ${0.5}^{\circ}$ at the eye. If it is looked through the telescope, the angle subtended by the moon’s image will be

Discussion

11907.	In the following diagram, the workdone in moving a point charge from point P to the points A, B and C respectively will be ( A, B and C are in semi circle)
Answer» In the following diagram, the workdone in moving a point charge from point $P$ to the points $A, B$ and $C$ respectively will be ( $A, B$ and $C$ are in semi circle)

Discussion

11908.	In a hydroelectric power station, the height of the dam is 10 m. How many kg of water must fall per second on the blades of a turbine in order to generate 1 MW of electrical power? Take g=10 ms−2.
Answer» In a hydroelectric power station, the height of the dam is 10 m. How many kg of water must fall per second on the blades of a turbine in order to generate 1 MW of electrical power? Take $g = 10 m s^{- 2}$ .

Discussion

11909.	A particle moves from position vector r1=3i^+2j^-6k^ to position vector r2=14i^+13j^+9k^ under the action of force 4i^+j^ +3k^N.Find the work done.
Answer» A particle moves from position vector r1=3i^+2j^-6k^ to position vector r2=14i^+13j^+9k^ under the action of force 4i^+j^ +3k^N.Find the work done.

Discussion

11910.	A block rests on a rough incline plane making an angle of 30∘ with the horizontal. The coefficient of static friction between the block and the plane is 0.8. If the frictional force on the block is 10 N, the mass of the block (in kg ) is (take g=10 m/s2)
Answer» A block rests on a rough incline plane making an angle of $30^{\circ}$ with the horizontal. The coefficient of static friction between the block and the plane is $0.8$ . If the frictional force on the block is $10 N$ , the mass of the block (in $kg$ ) is (take $g = 10 {m/s}^{2})$

Discussion

11911.	Two discs of moments of inertia I1 and I2 about their respective axes (normal to the disc and passing through the centre), and rotating with angular speeds ω1 and ω2 are brought into contact face to face with their axes of rotation coincident. (a) What is the angular speed of the two-disc system? Show that the kinetic energy of the combined system is less than the sum of the initial kinetic energies of the two discs. How do you account for this loss in energy? Take ω1≠ω2
Answer» Two discs of moments of inertia $I_{1}$ and $I_{2}$ about their respective axes (normal to the disc and passing through the centre), and rotating with angular speeds $ω_{1}$ and $ω_{2}$ are brought into contact face to face with their axes of rotation coincident. (a) What is the angular speed of the two-disc system? Show that the kinetic energy of the combined system is less than the sum of the initial kinetic energies of the two discs. How do you account for this loss in energy? Take $ω_{1} \neq ω_{2}$

11911.

Two discs of moments of inertia I1 and I2 about their respective axes (normal to the disc and passing through the centre), and rotating with angular speeds ω1 and ω2 are brought into contact face to face with their axes of rotation coincident. (a) What is the angular speed of the two-disc system? Show that the kinetic energy of the combined system is less than the sum of the initial kinetic energies of the two discs. How do you account for this loss in energy? Take ω1≠ω2

Answer»

Two discs of moments of inertia $I_{1}$ and $I_{2}$ about their respective axes (normal to the disc and passing through the centre), and rotating with angular speeds $ω_{1}$ and $ω_{2}$ are brought into contact face to face with their axes of rotation coincident.

(a) What is the angular speed of the two-disc system?

Show that the kinetic energy of the combined system is less than the sum of the initial kinetic energies of the two discs. How do you account for this loss in energy? Take $ω_{1} \neq ω_{2}$

Discussion

11912.	Comment on the correctness of the following two statementsStatement I => The electrical field calculated by Gauss’s law is the field only due to the charges inside the Gaussian surface.Statement II => The flux of the electric field through a closed surface due to all the charges (inside and outside the surface), is equal to the flux only due to the charges enclosed by the surface.
Answer» Comment on the correctness of the following two statements Statement I => The electrical field calculated by Gauss’s law is the field only due to the charges inside the Gaussian surface. Statement II => The flux of the electric field through a closed surface due to all the charges (inside and outside the surface), is equal to the flux only due to the charges enclosed by the surface.

11912.

Comment on the correctness of the following two statementsStatement I => The electrical field calculated by Gauss’s law is the field only due to the charges inside the Gaussian surface.Statement II => The flux of the electric field through a closed surface due to all the charges (inside and outside the surface), is equal to the flux only due to the charges enclosed by the surface.

Answer»

Comment on the correctness of the following two statements

Statement I => The electrical field calculated by Gauss’s law is the field only due to the charges inside the Gaussian surface.

Statement II => The flux of the electric field through a closed surface due to all the charges (inside and outside the surface), is equal to the flux only due to the charges enclosed by the surface.

Discussion

11913.	The door of an almirah is 6 ft high, 1.5 ft wide and weighs 8 kg. The door is supported by two hinges situated at a distance of 1 ft from the top and bottom ends. Assuming force exerted on the hinges are equal, the magnitude of the force is [Take g=10 m/s2]
Answer» The door of an almirah is $6 ft$ high, $1.5 ft$ wide and weighs $8 kg$ . The door is supported by two hinges situated at a distance of $1 ft$ from the top and bottom ends. Assuming force exerted on the hinges are equal, the magnitude of the force is [Take $g = 10 {m/s}^{2}$ ]

Discussion

11914.	If we talk about discharge tube experiment we say that the rays move towards electric field or magnetic field and show some acceleration so the ray at that time behaves like what?
Answer» If we talk about discharge tube experiment we say that the rays move towards electric field or magnetic field and show some acceleration so the ray at that time behaves like what?

Discussion

11915.	In YDSE, phase difference between the interfering waves at a point on screen having intensity less than the average intensity on screen may be :
Answer» In YDSE, phase difference between the interfering waves at a point on screen having intensity less than the average intensity on screen may be :

Discussion

11916.	A parallel plate capacitor made of circular plates each of radius R=6 cm has a capacitance C=100 pF. The capacitor is connected to a 230 V AC supply with an angular frequency of 300 rad/s. Determine the amplitude of the magnetic field at point 3 cm from the axis between the plates.
Answer» A parallel plate capacitor made of circular plates each of radius $R = 6 cm$ has a capacitance $C = 100 pF .$ The capacitor is connected to a $230 V A C$ supply with an angular frequency of $300 rad/s$ . Determine the amplitude of the magnetic field at point $3 cm$ from the axis between the plates.

Discussion

11917.	The maximum value of the block m2 for which the system will remain in equilibrium (coefficient of friction between block m1 and plane surface is μ, pulleys are massless) is :
Answer» The maximum value of the block $m_{2}$ for which the system will remain in equilibrium (coefficient of friction between block $m_{1}$ and plane surface is $μ$ , pulleys are massless) is :

Discussion

11918.	A stone tied to an inextensible string of length 1 m is released from horizontal position. The stone is free to revolve in a vertical plane around the other end of the string. Find the angular speed of the stone when the string makes an angle θ=30∘ with horizontal. Take g=10 m/s2.
Answer» A stone tied to an inextensible string of length $1 m$ is released from horizontal position. The stone is free to revolve in a vertical plane around the other end of the string. Find the angular speed of the stone when the string makes an angle $θ = 30^{\circ}$ with horizontal. Take $g = 10 {m/s}^{2}$ .

Discussion

11919.	Potential drop across 5 Ω is 10 V, then EMF of the battery is
Answer» Potential drop across $5 Ω$ is $10 V$ , then EMF of the battery is

Discussion

11920.	A hollow cylinder of length 32 cm , external diameter 20 cm and thickness 4 mm is to be made . What length of a solid right circular cylinder of diameter 4 cm is required to recast this hollow cylinder ??
Answer» A hollow cylinder of length 32 cm , external diameter 20 cm and thickness 4 mm is to be made . What length of a solid right circular cylinder of diameter 4 cm is required to recast this hollow cylinder ??

Discussion

11921.	A wheel of moment of inertia 5 × 10–3 kgm2 is making 20 rev/s. The torque required to stop it in 10 s is- Options: a- 2 × 10–2 Nm b- 2 × 102 Nm c- 4 × 10–2 Nm d- 4 × 102 Nm
Answer» A wheel of moment of inertia 5 × 10–3 kgm2 is making 20 rev/s. The torque required to stop it in 10 s is- Options: a- 2 × 10–2 Nm b- 2 × 102 Nm c- 4 × 10–2 Nm d- 4 × 102 Nm

Discussion

11922.	Q. If a simple pendulum is taken to a place where g decreases by 2% then time period will? a\rbrack increase by 2% b\rbrack increase by 1% c\rbrack increase by 4% d\rbrack decrease by 1%
Answer» Q. If a simple pendulum is taken to a place where g decreases by 2% then time period will? a\rbrack increase by 2% b\rbrack increase by 1% c\rbrack increase by 4% d\rbrack decrease by 1%

Discussion

11923.	Is Laws of reflection are not applicable on rough surface or Irreguler Reflection dose not follows Laws of Reflection(\angle i=\angle r)
Answer» Is Laws of reflection are not applicable on rough surface or Irreguler Reflection dose not follows Laws of Reflection(\angle i=\angle r)

Discussion

11924.	A sphere of radius 1.00 cm is placed in the path of a parallel beam of light of large aperture. The intensity of the light is 0.50 W/cm2. If the sphere partially absorbs (α=0.25) the radiation falling on it, find the force exerted by the light beam on the sphere.
Answer» A sphere of radius $1.00 cm$ is placed in the path of a parallel beam of light of large aperture. The intensity of the light is $0.50 {W/cm}^{2} .$ If the sphere partially absorbs $(α = 0.25)$ the radiation falling on it, find the force exerted by the light beam on the sphere.

Discussion

11925.	A magnetic needle lying parallel to a magnetic field requires W units of work to turn it through 60∘, the torque needed to maintain the needle in this position will be
Answer» A magnetic needle lying parallel to a magnetic field requires $W$ units of work to turn it through $60^{\circ}$ , the torque needed to maintain the needle in this position will be

Discussion

11926.	The angular speed of a wheel of radius 0.50 m moving with the speed of 20 m/s is:
Answer» The angular speed of a wheel of radius 0.50 m moving with the speed of 20 m/s is:

Discussion

11927.	A body revolves with a constant speed V in a circular path of radius R. What is the magnitude of its average acceleration during motion between two points in diametrically opposite direction??
Answer» A body revolves with a constant speed V in a circular path of radius R. What is the magnitude of its average acceleration during motion between two points in diametrically opposite direction??

Discussion

11928.	Two forces P and Q act at such that the resultanat R=P If P is doubled find the angel made by the new resultatnt with respect to the force Q
Answer» Two forces P and Q act at such that the resultanat R=P If P is doubled find the angel made by the new resultatnt with respect to the force Q

Discussion

11929.	A solenoid of 0.4 m length with 500 turns carries a current of 3 A. A coil of 10 turns and of radius 0.01 m carries of 0.4 A. The torque required to hold the coil with its axis at right angle to that of the solenoid is :
Answer» A solenoid of $0.4 m$ length with $500$ turns carries a current of $3 A .$ A coil of $10$ turns and of radius $0.01 m$ carries of $0.4 A$ . The torque required to hold the coil with its axis at right angle to that of the solenoid is :

Discussion

11930.	Question 14What is the sum of all the angles of a pentagon?a) 180∘b) 360∘c) 540∘d) 720∘
Answer» Question 14 What is the sum of all the angles of a pentagon? a) $180^{\circ}$ b) $360^{\circ}$ c) $540^{\circ}$ d) $720^{\circ}$

Discussion

11931.	A heavy mass is attached to a thin wire and is whirled in a vertical circle. The wire is most likely to break.
Answer» A heavy mass is attached to a thin wire and is whirled in a vertical circle. The wire is most likely to break.

Discussion

11932.	A parallel beam of light is incident from air at an angle α on the side PQ of a right angled triangular prism of refractive index μ=√2. Light undergoes total internal reflection at the face PR when α has a minimum value of 45∘. The angle θ of the prism is:
Answer» A parallel beam of light is incident from air at an angle $α$ on the side $PQ$ of a right angled triangular prism of refractive index $μ = \sqrt{2} .$ Light undergoes total internal reflection at the face $PR$ when $α$ has a minimum value of $45^{\circ}$ . The angle $θ$ of the prism is:

Discussion

11933.	In the transistor amplifier circuit shown in the figure below, the transistor has the following parameters : βdc=60, VBE=0.7Vhis→∞, hfc→∞,The capacitance CC can be assumed to be infiniteUnder the dc conditions, the collector-to-emitter voltage drop is ___V.6
Answer» In the transistor amplifier circuit shown in the figure below, the transistor has the following parameters : $β_{d c} = 60,$ $V_{B E} = 0.7 V$ $h_{i s} \to \infty,$ $h_{f c} \to \infty,$ The capacitance $C_{C}$ can be assumed to be infinite Under the dc conditions, the collector-to-emitter voltage drop is ___V. 6

Discussion

11934.	Two waves of intensity l2 and I2 interfere. The maximum intensity produced to the minimum intensity is in the ratio a . Then, I1/I2is equal to
Answer» Two waves of intensity $l_{2} and I_{2}$ interfere. The maximum intensity produced to the minimum intensity is in the ratio a . Then, $I_{1} / I_{2}$ is equal to

Discussion

11935.	A body is projected at an angle of 30∘ with the horizontal and with a speed of 30 ms−1. What is the angle with the horizontal after 1.5 seconds ? (g=10 ms−2).
Answer» A body is projected at an angle of $30^{\circ}$ with the horizontal and with a speed of $30 m s^{- 1} .$ What is the angle with the horizontal after $1.5$ seconds ? $(g = 10 m s^{- 2}) .$

Discussion

11936.	A X-ray tube operates at potential 15 kV. Findthe minimum wavelength of X-ray
Answer» A X-ray tube operates at potential 15 kV. Findthe minimum wavelength of X-ray

Discussion

11937.	130.A 6 volt battery is combined with a 3 m long wire of identical thickness and combined with 100 ohm resistance in the series along to other 100 ohm resistor. The potential difference between two points on the separated wire having 50 cm distance. (1) 2V (2)3V (3) 1V (4) 0.5 V
Answer» 130.A 6 volt battery is combined with a 3 m long wire of identical thickness and combined with 100 ohm resistance in the series along to other 100 ohm resistor. The potential difference between two points on the separated wire having 50 cm distance. (1) 2V (2)3V (3) 1V (4) 0.5 V

Discussion

11938.	The figure represents the voltage applied across a pure inductor. The diagram which correctly represents the variation of current i with time t is given by
Answer» The figure represents the voltage applied across a pure inductor. The diagram which correctly represents the variation of current $i$ with time $t$ is given by

Discussion

11939.	The given graph shows variation (with distance r from centre) of: Potential of a uniformly charged spherePotential of a uniformly charged spherical shellElectric field of uniformly charged spherical shellElectric field of uniformly charged sphere
Answer» The given graph shows variation (with distance $r$ from centre) of: Potential of a uniformly charged sphere Potential of a uniformly charged spherical shell Electric field of uniformly charged spherical shell Electric field of uniformly charged sphere

11939.

The given graph shows variation (with distance r from centre) of: Potential of a uniformly charged spherePotential of a uniformly charged spherical shellElectric field of uniformly charged spherical shellElectric field of uniformly charged sphere

Answer»

The given graph shows variation (with distance $r$ from centre) of:

Potential of a uniformly charged sphere
Potential of a uniformly charged spherical shell
Electric field of uniformly charged spherical shell
Electric field of uniformly charged sphere

Discussion

11940.	In an electromagnetic wave in free space the root mean square value of the electric field is Erms=6 V/m. The peak value of the magnetic field is
Answer» In an electromagnetic wave in free space the root mean square value of the electric field is $E_{r m s} = 6 V/m .$ The peak value of the magnetic field is

Discussion

11941.	A small conducting sphere of radius r is lying concentrically inside a bigger hollow Conducting of radius R. The bigger and smaller spheres are charge with Q and q (Q>q) and are insulated from each other. The potential difference between the spheres will be
Answer» A small conducting sphere of radius r is lying concentrically inside a bigger hollow Conducting of radius R. The bigger and smaller spheres are charge with Q and q (Q>q) and are insulated from each other. The potential difference between the spheres will be

Discussion

11942.	A man is standing in a lift moving upwards with a constant speed of 10 ms−1. The man drops a coin from a height of 4.9 m. If g=9.8 ms−2, the coin reaches the floor of the lift after a time
Answer» A man is standing in a lift moving upwards with a constant speed of $10 {ms}^{- 1}$ . The man drops a coin from a height of $4.9 m$ . If $g = 9.8 {ms}^{- 2}$ , the coin reaches the floor of the lift after a time

Discussion

11943.	A coil of area 100 cm2 having 500 turns carries a current of 1 mA. It is suspended in a uniform magnetic field of 10−3 wb /m2. If the torque acting on the coil is 250×10−8 Nm , then the angle made by the plane of the coil with the field is
Answer» A coil of area $100 {cm}^{2}$ having $500$ turns carries a current of $1 mA$ . It is suspended in a uniform magnetic field of $10^{- 3} {wb /m}^{2}$ . If the torque acting on the coil is $250 \times 10^{- 8} Nm$ , then the angle made by the plane of the coil with the field is

Discussion

11944.	An AC source of angular frequency ω is fed across a resistor R and a capacitor C in series. The current registered is I. If now the frequency of source is changed to ω3 (but maintaining the same voltage), the current in the circuit is found to be halved. The ratio of reactance to resistance at the original frequency ω is equal to √k.the value of k is
Answer» An AC source of angular frequency $ω$ is fed across a resistor $R$ and a capacitor $C$ in series. The current registered is $I$ . If now the frequency of source is changed to $\frac{ω}{3}$ (but maintaining the same voltage), the current in the circuit is found to be halved. The ratio of reactance to resistance at the original frequency $ω$ is equal to $\sqrt{k}$ .the value of $k$ is

Discussion

11945.	136.As the temperature of a metallic resistor is increased,the product of its resistivity & conductivity ? increase,decrease or remains constant
Answer» 136.As the temperature of a metallic resistor is increased,the product of its resistivity & conductivity ? increase,decrease or remains constant

Discussion

11946.	You must have met some interesting characters in your neighbourhood or among your relatives. Write a humorous piece about their idiosyncrasies. Try to adopt the author’s rambling style, if you can.
Answer» You must have met some interesting characters in your neighbourhood or among your relatives. Write a humorous piece about their idiosyncrasies. Try to adopt the author’s rambling style, if you can.

Discussion

11947.	The mean square speed of the molecules of a gas at absolute temperature T is proportional to
Answer» The mean square speed of the molecules of a gas at absolute temperature T is proportional to

Discussion

11948.	From a circular disc of radius R, a square is cut out with a radius as its diagonal. The centre of mass of remainder is at a distance (from the centre)
Answer» From a circular disc of radius R, a square is cut out with a radius as its diagonal. The centre of mass of remainder is at a distance (from the centre)

Discussion

11949.	An ice-box is made of wood 1.75 cm thick, lined inside with cork 2 cm thick. If the temperature of the inner surface of the cork is steady at 0°C and that of the outer surface is steady at 12∘C, what is the temperature of the interface? The thermal conductivity of wood is 5 times that of cork.
Answer» An ice-box is made of wood 1.75 cm thick, lined inside with cork 2 cm thick. If the temperature of the inner surface of the cork is steady at 0°C and that of the outer surface is steady at $12^{\circ} C$ , what is the temperature of the interface? The thermal conductivity of wood is 5 times that of cork.

11949.

An ice-box is made of wood 1.75 cm thick, lined inside with cork 2 cm thick. If the temperature of the inner surface of the cork is steady at 0°C and that of the outer surface is steady at 12∘C, what is the temperature of the interface? The thermal conductivity of wood is 5 times that of cork.

Answer»

An ice-box is made of wood 1.75 cm thick, lined inside with cork 2 cm thick. If the temperature of the inner surface of the cork is steady at 0°C and that of the outer surface is steady at $12^{\circ} C$ , what is the temperature of the interface? The thermal conductivity of wood is 5 times that of cork.

Discussion

11950.	An observer move towards a stationary source of sound with a velocity equal to one fifth of the velocity of sound. The apparent change in frequency is
Answer» An observer move towards a stationary source of sound with a velocity equal to one fifth of the velocity of sound. The apparent change in frequency is

Discussion

Explore topic-wise InterviewSolutions in .

A particle in S.H.M with frequency f. The frequency at which its kinetic energy changes into potential energy is

A proton and an α -particle are accelerated through a potential difference of 100 V. The ratio of the wavelength associated with the proton to that associated with an α-particle is

On the horizontal surface of a truck (µ=0.6),a block of mass 1 kg is placed. If the truck is accelerating at the rate of 5m/sec​​​​2 then frictional force on the block will be

A block of mass 1 kg is placed on a rough wedge which is fixed on an elevator moving upward with constant velocity 2m/s .The block m is at rest wrt wedge .Net reaction force on the block is

AMZ→BM−12Z−1 The number of α and β particles emitted in the above conversion is

The focal lengths of the objective and eye-piece of a telescope are respectively 100 cm and 2 cm. The moon subtends an angle of 0.5∘ at the eye. If it is looked through the telescope, the angle subtended by the moon’s image will be

In the following diagram, the workdone in moving a point charge from point P to the points A, B and C respectively will be ( A, B and C are in semi circle)

In a hydroelectric power station, the height of the dam is 10 m. How many kg of water must fall per second on the blades of a turbine in order to generate 1 MW of electrical power? Take g=10 ms−2.

A particle moves from position vector r1=3i^+2j^-6k^ to position vector r2=14i^+13j^+9k^ under the action of force 4i^+j^ +3k^N.Find the work done.

A block rests on a rough incline plane making an angle of 30∘ with the horizontal. The coefficient of static friction between the block and the plane is 0.8. If the frictional force on the block is 10 N, the mass of the block (in kg ) is (take g=10 m/s2)

The door of an almirah is 6 ft high, 1.5 ft wide and weighs 8 kg. The door is supported by two hinges situated at a distance of 1 ft from the top and bottom ends. Assuming force exerted on the hinges are equal, the magnitude of the force is [Take g=10 m/s2]

If we talk about discharge tube experiment we say that the rays move towards electric field or magnetic field and show some acceleration so the ray at that time behaves like what?

In YDSE, phase difference between the interfering waves at a point on screen having intensity less than the average intensity on screen may be :

A parallel plate capacitor made of circular plates each of radius R=6 cm has a capacitance C=100 pF. The capacitor is connected to a 230 V AC supply with an angular frequency of 300 rad/s. Determine the amplitude of the magnetic field at point 3 cm from the axis between the plates.

The maximum value of the block m2 for which the system will remain in equilibrium (coefficient of friction between block m1 and plane surface is μ, pulleys are massless) is :

A stone tied to an inextensible string of length 1 m is released from horizontal position. The stone is free to revolve in a vertical plane around the other end of the string. Find the angular speed of the stone when the string makes an angle θ=30∘ with horizontal. Take g=10 m/s2.

Potential drop across 5 Ω is 10 V, then EMF of the battery is

A hollow cylinder of length 32 cm , external diameter 20 cm and thickness 4 mm is to be made . What length of a solid right circular cylinder of diameter 4 cm is required to recast this hollow cylinder ??

A wheel of moment of inertia 5 × 10–3 kgm2 is making 20 rev/s. The torque required to stop it in 10 s is- Options: a- 2 × 10–2 Nm b- 2 × 102 Nm c- 4 × 10–2 Nm d- 4 × 102 Nm

Q. If a simple pendulum is taken to a place where g decreases by 2% then time period will? a\rbrack increase by 2% b\rbrack increase by 1% c\rbrack increase by 4% d\rbrack decrease by 1%

Is Laws of reflection are not applicable on rough surface or Irreguler Reflection dose not follows Laws of Reflection(\angle i=\angle r)

A sphere of radius 1.00 cm is placed in the path of a parallel beam of light of large aperture. The intensity of the light is 0.50 W/cm2. If the sphere partially absorbs (α=0.25) the radiation falling on it, find the force exerted by the light beam on the sphere.

A magnetic needle lying parallel to a magnetic field requires W units of work to turn it through 60∘, the torque needed to maintain the needle in this position will be

The angular speed of a wheel of radius 0.50 m moving with the speed of 20 m/s is:

A body revolves with a constant speed V in a circular path of radius R. What is the magnitude of its average acceleration during motion between two points in diametrically opposite direction??

Two forces P and Q act at such that the resultanat R=P If P is doubled find the angel made by the new resultatnt with respect to the force Q

A solenoid of 0.4 m length with 500 turns carries a current of 3 A. A coil of 10 turns and of radius 0.01 m carries of 0.4 A. The torque required to hold the coil with its axis at right angle to that of the solenoid is :

Question 14What is the sum of all the angles of a pentagon?a) 180∘b) 360∘c) 540∘d) 720∘

A heavy mass is attached to a thin wire and is whirled in a vertical circle. The wire is most likely to break.

A parallel beam of light is incident from air at an angle α on the side PQ of a right angled triangular prism of refractive index μ=√2. Light undergoes total internal reflection at the face PR when α has a minimum value of 45∘. The angle θ of the prism is:

In the transistor amplifier circuit shown in the figure below, the transistor has the following parameters : βdc=60, VBE=0.7Vhis→∞, hfc→∞,The capacitance CC can be assumed to be infiniteUnder the dc conditions, the collector-to-emitter voltage drop is ___V.6

Two waves of intensity l2 and I2 interfere. The maximum intensity produced to the minimum intensity is in the ratio a . Then, I1/I2is equal to

A body is projected at an angle of 30∘ with the horizontal and with a speed of 30 ms−1. What is the angle with the horizontal after 1.5 seconds ? (g=10 ms−2).

A X-ray tube operates at potential 15 kV. Findthe minimum wavelength of X-ray

130.A 6 volt battery is combined with a 3 m long wire of identical thickness and combined with 100 ohm resistance in the series along to other 100 ohm resistor. The potential difference between two points on the separated wire having 50 cm distance. (1) 2V (2)3V (3) 1V (4) 0.5 V

The figure represents the voltage applied across a pure inductor. The diagram which correctly represents the variation of current i with time t is given by

The given graph shows variation (with distance r from centre) of: Potential of a uniformly charged spherePotential of a uniformly charged spherical shellElectric field of uniformly charged spherical shellElectric field of uniformly charged sphere

In an electromagnetic wave in free space the root mean square value of the electric field is Erms=6 V/m. The peak value of the magnetic field is

A small conducting sphere of radius r is lying concentrically inside a bigger hollow Conducting of radius R. The bigger and smaller spheres are charge with Q and q (Q>q) and are insulated from each other. The potential difference between the spheres will be

A man is standing in a lift moving upwards with a constant speed of 10 ms−1. The man drops a coin from a height of 4.9 m. If g=9.8 ms−2, the coin reaches the floor of the lift after a time

A coil of area 100 cm2 having 500 turns carries a current of 1 mA. It is suspended in a uniform magnetic field of 10−3 wb /m2. If the torque acting on the coil is 250×10−8 Nm , then the angle made by the plane of the coil with the field is

136.As the temperature of a metallic resistor is increased,the product of its resistivity & conductivity ? increase,decrease or remains constant

You must have met some interesting characters in your neighbourhood or among your relatives. Write a humorous piece about their idiosyncrasies. Try to adopt the author’s rambling style, if you can.

The mean square speed of the molecules of a gas at absolute temperature T is proportional to

From a circular disc of radius R, a square is cut out with a radius as its diagonal. The centre of mass of remainder is at a distance (from the centre)

An ice-box is made of wood 1.75 cm thick, lined inside with cork 2 cm thick. If the temperature of the inner surface of the cork is steady at 0°C and that of the outer surface is steady at 12∘C, what is the temperature of the interface? The thermal conductivity of wood is 5 times that of cork.

An observer move towards a stationary source of sound with a velocity equal to one fifth of the velocity of sound. The apparent change in frequency is

On the horizontal surface of a truck (µ=0.6),a block of mass 1 kg is placed. If the truck is accelerating at the rate of 5m/sec2 then frictional force on the block will be