50278 + Interview Questions in Physics

1.	The Heights of mercury surface in the two arms of the manometer shown are 2 cm and 8 cm. find the pressure of the gas in the cylinder? Patm = 105 N/m2
Answer» The Heights of mercury surface in the two arms of the manometer shown are 2 cm and 8 cm. find the pressure of the gas in the cylinder? P_atm = 10⁵N/m²

1.

The Heights of mercury surface in the two arms of the manometer shown are 2 cm and 8 cm. find the pressure of the gas in the cylinder? Patm = 105 N/m2

Answer»

The Heights of mercury surface in the two arms of the manometer shown are 2 cm and 8 cm. find the pressure of the gas in the cylinder? P_atm = 10⁵N/m²

Discussion

2.	An electron having energy 10 eV is circulating in a plane at right angle to a uniform field of magnetic induction 10−4 Wb/m2(=1.0 gauss), the orbital radius of electron is
Answer» An electron having energy $10 eV$ is circulating in a plane at right angle to a uniform field of magnetic induction $10^{- 4} {Wb/m}^{2} (= 1.0 gauss)$ , the orbital radius of electron is

Discussion

3.	In mesoscopic physics the laws of macroscopic physics are applicable or not?
Answer» In mesoscopic physics the laws of macroscopic physics are applicable or not?

Discussion

4.	A thin rod of length L is lying along the x - axis with its ends at x =0 and x= L. Its linear density (mass/length) varies with x as (xL)n, where k is a constant and n can be zero or any positive number. If the position xcm of the centre of mass of the rod is plotted against n, which of the following graphs best approximates the dependence of xcm on n
Answer» A thin rod of length L is lying along the x - axis with its ends at x =0 and x= L. Its linear density (mass/length) varies with x as ${(\frac{x}{L})}^{n}$ , where k is a constant and n can be zero or any positive number. If the position $x_{c m}$ of the centre of mass of the rod is plotted against n, which of the following graphs best approximates the dependence of $x_{c m}$ on n

Discussion

5.	In the given figure, a particle A moves along the line y=30 m with a constant velocity of magnitude 3 m/s and parallel to the x− axis. At the instant particle A passes the y− axis, the particle B leaves the origin with a zero initial speed and a constant acceleration of magnitude 0.40 m/s2. What angle θ between→aB and the positive direction of the y−axis would result in a collision?
Answer» In the given figure, a particle $A$ moves along the line $y = 30 m$ with a constant velocity of magnitude $3 m/s$ and parallel to the $x -$ axis. At the instant particle $A$ passes the $y -$ axis, the particle $B$ leaves the origin with a zero initial speed and a constant acceleration of magnitude $0.40 {m/s}^{2}$ . What angle $θ$ between ${\to a}_{B}$ and the positive direction of the $y -$ axis would result in a collision?

Discussion

6.	A ring oscillator consisting of 3 inverters is running at a frequency of 1 MHz. The value of propagation delay per gate is________nsec. (Answer upto 2 decimal places)71.43
Answer» A ring oscillator consisting of 3 inverters is running at a frequency of 1 MHz. The value of propagation delay per gate is________nsec. (Answer upto 2 decimal places) 71.43

Discussion

7.	An iron rod of susceptibility 599 is subjected to a magnetizing field of 1200 Am−1. The permeability of the material of the rod is :Take, μ0=4π×10−7 TmA−1
Answer» An iron rod of susceptibility $599$ is subjected to a magnetizing field of $1200 {Am}^{- 1}$ . The permeability of the material of the rod is : Take, $μ_{0} = 4 π \times 10^{- 7} {TmA}^{- 1}$

Discussion

8.	A capacitor has capacitance of 6 nF, maximum voltage it can sustain is 40 volt. It is in series with other capacitor 3 nF and this capacitor can sustain 30 volt, what is maximum voltage that can be applied in series.
Answer» A capacitor has capacitance of $6 n F$ , maximum voltage it can sustain is $40$ volt. It is in series with other capacitor $3 n F$ and this capacitor can sustain $30$ volt, what is maximum voltage that can be applied in series.

Discussion

9.	f ICOM is the moment of inertia of a body about an axis passing through its centre of mass and I1, I2 are moment of inertia of the same body about axis at a distance L1 and L2 (where L1 < L2) from the centre and the two axes are parallel to the axis passing through the centre of mass, thenOptions: ICOM > I2 > I1 ICOM < I2 > I1 ICOM < I1 < I2 ICOM = I2 = I1
Answer» f ICOM is the moment of inertia of a body about an axis passing through its centre of mass and I1, I2 are moment of inertia of the same body about axis at a distance L1 and L2 (where L1 < L2) from the centre and the two axes are parallel to the axis passing through the centre of mass, then Options: ICOM > I2 > I1 ICOM < I2 > I1 ICOM < I1 < I2 ICOM = I2 = I1

Discussion

10.	two projectiles A and B are thrown from the same point with velocities v and v/2, respectively.if B is thrown at an angle of 45 degree with horizontal, what is the inclination of A when their ranges are the same
Answer» two projectiles A and B are thrown from the same point with velocities v and v/2, respectively.if B is thrown at an angle of 45 degree with horizontal, what is the inclination of A when their ranges are the same

Discussion

11.	Gas in a cylinder is maintained at 10 atm pressure and 300 K temperature. The cylinder will explode if pressure of gas goes beyond 15 atm. What is the maximum temperature to which gas can be heated?
Answer» Gas in a cylinder is maintained at $10 a t m$ pressure and $300 K$ temperature. The cylinder will explode if pressure of gas goes beyond $15 a t m$ . What is the maximum temperature to which gas can be heated?

Discussion

12.	A force 10 N acts tangentially at the highest point of a solid sphere of mass 10 kg kept on a rough horizontal plane. If the sphere rolls without slipping, find the acceleration of the centre of the sphere (in m/s2).
Answer» A force $10 N$ acts tangentially at the highest point of a solid sphere of mass $10 kg$ kept on a rough horizontal plane. If the sphere rolls without slipping, find the acceleration of the centre of the sphere (in $m / s^{2}$ ).

Discussion

13.	Knowing that mass of Moon is M81 where M is the mass of Earth, find the distance of the point where gravitational field due to Earth and Moon cancel each other, from the Moon, Given that distance between Earth and Moon is 60 R. Where R is the radius of Earth
Answer» Knowing that mass of Moon is $\frac{M}{81}$ where M is the mass of Earth, find the distance of the point where gravitational field due to Earth and Moon cancel each other, from the Moon, Given that distance between Earth and Moon is 60 R. Where R is the radius of Earth

Discussion

14.	A photon of wavelength 1 ˚A is completely absorbed by a surface. What is the momentum transferred by this photon?
Answer» A photon of wavelength $1 ˚ A$ is completely absorbed by a surface. What is the momentum transferred by this photon?

Discussion

15.	When we put a charge inside hollow metallic shell we say that the electric field is not zero as the gaussian surface is drawn just including charge kept but if we talk about whole shell from inside we can see that the sum of the charge kept inside the shell and induced charge on inner surface of shell due to that charge kept is zero so which case to consider when it is asked whether electric field is zero or not inside the shell ?And also is net electric field different from just electric field
Answer» When we put a charge inside hollow metallic shell we say that the electric field is not zero as the gaussian surface is drawn just including charge kept but if we talk about whole shell from inside we can see that the sum of the charge kept inside the shell and induced charge on inner surface of shell due to that charge kept is zero so which case to consider when it is asked whether electric field is zero or not inside the shell ? And also is net electric field different from just electric field

Discussion

16.	How many time constants will elapse before the energy stored in the capacitor reaches half of its equilibrium value in a charging RC circuit ?
Answer» How many time constants will elapse before the energy stored in the capacitor reaches half of its equilibrium value in a charging RC circuit ?

Discussion

17.	A fish is moving up vertically with speed 4 cm/s inside a pond. A bird is moving vertically downward (see figure). Velocity of the bird w.r.t. fish is 16 cm/s downward. Find out the actual velocity of the bird (in cm/s). Given refractive index of water is 43.
Answer» A fish is moving up vertically with speed 4 cm/s inside a pond. A bird is moving vertically downward (see figure). Velocity of the bird w.r.t. fish is 16 cm/s downward. Find out the actual velocity of the bird (in cm/s). Given refractive index of water is $\frac{4}{3}$ .

Discussion

18.	A block of mass 1 kg is situated on a rough inclined plane and is connected to a spring of spring constant 100 Nm−1 as shown in figure. The block is released from rest when the spring is unstretched. The block moves through a distance of 10 cm down the plane before coming to rest. Assuming that spring and pulley are massless, and the pulley is frictionless. Find the coefficient of friction between the block and the inclined surface.(Take g=10 ms−2)
Answer» A block of mass $1 kg$ is situated on a rough inclined plane and is connected to a spring of spring constant $100 {Nm}^{- 1}$ as shown in figure. The block is released from rest when the spring is unstretched. The block moves through a distance of $10 cm$ down the plane before coming to rest. Assuming that spring and pulley are massless, and the pulley is frictionless. Find the coefficient of friction between the block and the inclined surface. (Take $g = 10 {ms}^{- 2}$ )

Discussion

19.	A body falls from a height h on a horizontal surface and rebounds. Then it falls again and rebounds and so on. If the restitution coefficient is 13, the total distance covered by the body before it comes to rest is
Answer» A body falls from a height h on a horizontal surface and rebounds. Then it falls again and rebounds and so on. If the restitution coefficient is $\frac{1}{3}$ , the total distance covered by the body before it comes to rest is

Discussion

20.	A force of 15 N displaces a box on a horizontal surface through a distance of 10 m. Calculate the angle which the force makes with the direction of motion of the body, if work done is 75 J.
Answer» A force of $15 N$ displaces a box on a horizontal surface through a distance of $10 m$ . Calculate the angle which the force makes with the direction of motion of the body, if work done is $75 J$ .

Discussion

21.	a positively charged pendulum is oscillatinh in a uniform electic field poiting upwards.its time period as compared to that when it oscillates without electic field is.
Answer» a positively charged pendulum is oscillatinh in a uniform electic field poiting upwards.its time period as compared to that when it oscillates without electic field is.

Discussion

22.	the refractive indices of a glass prism for violet yellow and red colors are 1.790,1.795 and 1.805 respectively .the dispersive power of the prism
Answer» the refractive indices of a glass prism for violet yellow and red colors are 1.790,1.795 and 1.805 respectively .the dispersive power of the prism

Discussion

23.	A rod with a linear charge density of 3.5 C/m is 2.5 m long. What is the charge on it?
Answer» A rod with a linear charge density of 3.5 C/m is 2.5 m long. What is the charge on it?

Discussion

24.	Photons with energy 5 eV are incident on a cathode C in a photoelectric cell. The maximum energy of emitted photo electrons is 2 eV. When photons of energy 6 eV are incident on C, no photoelectrons will reach the anode A. The stopping potential of A relative to C is
Answer» Photons with energy $5 e V$ are incident on a cathode $C$ in a photoelectric cell. The maximum energy of emitted photo electrons is $2 e V$ . When photons of energy $6 e V$ are incident on $C$ , no photoelectrons will reach the anode $A$ . The stopping potential of $A$ relative to $C$ is

Discussion

25.	if two identicalspheres hacing charge 16c and -8 c are kept at certain dis†an ce then the force is F they are touched and again kept at same dis†an ce the force becomes
Answer» if two identicalspheres hacing charge 16c and -8 c are kept at certain dis†an ce then the force is F they are touched and again kept at same dis†an ce the force becomes

Discussion

26.	A ball of mass 0.25 kg attached to the ends of a string of length 1.96 m is rotating in a horizontal circle. The string will break, if tension is more than 25 N. What is the maximum velocity with which the ball can be rotated ?
Answer» A ball of mass $0.25 kg$ attached to the ends of a string of length $1.96 m$ is rotating in a horizontal circle. The string will break, if tension is more than $25 N$ . What is the maximum velocity with which the ball can be rotated ?

Discussion

27.	A man standing on a an ice pond want to move on ita)he has to crawl on itb)he has to sneeze and pitc)he can walk easily on itd)he has to roll on it
Answer» A man standing on a an ice pond want to move on it a)he has to crawl on it b)he has to sneeze and pit c)he can walk easily on it d)he has to roll on it

Discussion

28.	A series LCR circuit with R=20Ω,L=1.54 H andC=35μF is connected to a variable frequency 200 V ac supply. When the frequency of the supply equals the natural frequency of the circuit. What is the average power in kW transferred to the circuit in one complete cycle?
Answer» A series LCR circuit with $R = 20 Ω, L = 1.54 H a n d C = 35 μ F$ is connected to a variable frequency $200 V$ ac supply. When the frequency of the supply equals the natural frequency of the circuit. What is the average power in $kW$ transferred to the circuit in one complete cycle?

Discussion

29.	What is the equivalent resistance between point A and B
Answer» What is the equivalent resistance between point A and B

Discussion

30.	A ball of mass 0.1kg and moving with velocity 40 m per second strike up that and returned back in the opposite direction with the same speed. Calculate the change in linear movement of the ball.
Answer» A ball of mass 0.1kg and moving with velocity 40 m per second strike up that and returned back in the opposite direction with the same speed. Calculate the change in linear movement of the ball.

Discussion

31.	In a orthogonal cutting process the tool used has rake angle of zero degree. The measured cutting force and thrust force are 500 N and 250 N, respectively. The coefficient of friction between the tool and the chip is
Answer» In a orthogonal cutting process the tool used has rake angle of zero degree. The measured cutting force and thrust force are 500 N and 250 N, respectively. The coefficient of friction between the tool and the chip is

Discussion

32.	A metallic block of density 5 gm cm−3 and having dimensions 5 cm × 5 cm × 5 cm is weighed in water. Its apparent weight will be
Answer» A metallic block of density 5 gm $c m^{- 3}$ and having dimensions 5 cm $\times$ 5 cm $\times$ 5 cm is weighed in water. Its apparent weight will be

Discussion

33.	When a glass rod is rubbed with a silk cloth, charges appear on both. A similar phenomenon is observed with many other pairs ofbodies. Explain how this observation is consistent with the law ofconservation of charge.
Answer» When a glass rod is rubbed with a silk cloth, charges appear on both. A similar phenomenon is observed with many other pairs ofbodies. Explain how this observation is consistent with the law ofconservation of charge.

Discussion

34.	143.In the given diagram find the acceleration of the block with respect to the disk
Answer» 143.In the given diagram find the acceleration of the block with respect to the disk

Discussion

35.	A particle moves in circular path of radius R. If centripetal force F is kept constant but the angular velocity is doubled, the new radius of the path will be
Answer» A particle moves in circular path of radius $R$ . If centripetal force $F$ is kept constant but the angular velocity is doubled, the new radius of the path will be

Discussion

36.	a positive charge q1 is placed at (a,0) and another positive point charge q2 is placed at (0,a) find the force on q1
Answer» a positive charge q1 is placed at (a,0) and another positive point charge q2 is placed at (0,a) find the force on q1

Discussion

37.	Why the current flows from negative end to positive end?
Answer» Why the current flows from negative end to positive end?

Discussion

38.	An electromagnetic wave travelling through a transparent medium is given by Ex(y,t)=Eoxsin2π[y5×10−7−4×1014t] in SI units. Then what is the refractive index of the medium?
Answer» An electromagnetic wave travelling through a transparent medium is given by $E_{x} (y, t) = E_{o x} s i n 2 π [\frac{y}{5 \times 10^{- 7}} - 4 \times 10^{14} t]$ in SI units. Then what is the refractive index of the medium?

Discussion

39.	Whatshould be the distance between the object in Exercise 9.30 and themagnifying glass if the virtual image of each square in the figure isto have an area of 6.25 mm2.Would you be able to see the squares distinctly with your eyes veryclose to the magnifier?[Note:Exercises9.29 to 9.31 will help you clearly understand the difference betweenmagnification in absolute size and the angular magnification (ormagnifying power) of an instrument.]
Answer» What should be the distance between the object in Exercise 9.30 and the magnifying glass if the virtual image of each square in the figure is to have an area of 6.25 mm². Would you be able to see the squares distinctly with your eyes very close to the magnifier? [Note: Exercises 9.29 to 9.31 will help you clearly understand the difference between magnification in absolute size and the angular magnification (or magnifying power) of an instrument.]

39.

Whatshould be the distance between the object in Exercise 9.30 and themagnifying glass if the virtual image of each square in the figure isto have an area of 6.25 mm2.Would you be able to see the squares distinctly with your eyes veryclose to the magnifier?[Note:Exercises9.29 to 9.31 will help you clearly understand the difference betweenmagnification in absolute size and the angular magnification (ormagnifying power) of an instrument.]

Answer»

What
should be the distance between the object in Exercise 9.30 and the
magnifying glass if the virtual image of each square in the figure is
to have an area of 6.25 mm².
Would you be able to see the squares distinctly with your eyes very
close to the magnifier?

[Note:
Exercises
9.29 to 9.31 will help you clearly understand the difference between
magnification in absolute size and the angular magnification (or
magnifying power) of an instrument.]

Discussion

40.	Plot the corresponding reference circle for each of the following simple harmonic motions. Indicate the initial (t =0) position of the particle, the radius of the circle, OSCILLATIONS 365 and the angular speed of the rotating particle. For simplicity, the sense of rotation may be fixed to be anticlockwise in every case: (x is in cm and t is in s). (a) x = –2 sin (3t + π /3) (b) x = cos (π /6 – t) (c) x = 3 sin (2π t + π /4) (d) x = 2 cos π t
Answer» Plot the corresponding reference circle for each of the following simple harmonic motions. Indicate the initial (t =0) position of the particle, the radius of the circle, OSCILLATIONS 365 and the angular speed of the rotating particle. For simplicity, the sense of rotation may be fixed to be anticlockwise in every case: (x is in cm and t is in s). (a) x = –2 sin (3t + π /3) (b) x = cos (π /6 – t) (c) x = 3 sin (2π t + π /4) (d) x = 2 cos π t

Discussion

41.	Select the wrong statement about statement :1. Pressure is a scalar quantity. 2. Pressure is always compressive on nature. 3. Pressure at a point is same in all directions. 4. None of these
Answer» Select the wrong statement about statement : 1. Pressure is a scalar quantity. 2. Pressure is always compressive on nature. 3. Pressure at a point is same in all directions. 4. None of these

Discussion

42.	Unit vector parallel to the resultant of vectors →A=4^i−3^j and →B=8^i+8^j
Answer» Unit vector parallel to the resultant of vectors $\to A = 4^i - 3^j$ and $\to B = 8^i + 8^j$

Discussion

43.	The electric field associated with an e.m. wave in vacuum is given as →E=40cos(kz−6×108t)^i, where all quantities are in SI units. The value of the propagation constant k is,
Answer» The electric field associated with an e.m. wave in vacuum is given as $\to E = 40 cos (k z - 6 \times 10^{8} t)^i$ , where all quantities are in SI units. The value of the propagation constant $k$ is,

Discussion

44.	Two charges e and 3e are placed at a dis†an ce r. The dis†an ce of the point where the electric field intensity will be zero is
Answer» Two charges e and 3e are placed at a dis†an ce r. The dis†an ce of the point where the electric field intensity will be zero is

Discussion

45.	A planet is revolving around the sun in an elliptical orbit. Which of the following remains constant? a.Linear momentum. B.Angular momentum. C.Kinetic energy D.Potential energy.
Answer» A planet is revolving around the sun in an elliptical orbit. Which of the following remains constant? a.Linear momentum. B.Angular momentum. C.Kinetic energy D.Potential energy.

Discussion

46.	Voltage rating of a parallel plate capacitor is 500 V. Its dielectric can withstand a maximum electric field of 106 V/m. The plate area is 10−4m2. What is the dielectric constant if the capacitance is 15 pF?(given ϵ0=8.86×10−12 C2/Nm2).
Answer» Voltage rating of a parallel plate capacitor is $500 V$ . Its dielectric can withstand a maximum electric field of $10^{6} V / m$ . The plate area is $10^{- 4} m^{2}$ . What is the dielectric constant if the capacitance is $15 p F$ ? (given $ϵ_{0} = 8.86 \times 10^{- 12} C^{2} / N m^{2})$ .

Discussion

47.	A thin uniform circular disc of mass M and radius R is rotating with an angular velocity ω, in a horizontal plane about an axis passing through its centre and perpendicular to its plane. Another disc of same dimensions but of mass M4 is placed gently on the first disc co-axially. The final angular velocity of the system is
Answer» A thin uniform circular disc of mass $M$ and radius $R$ is rotating with an angular velocity $ω,$ in a horizontal plane about an axis passing through its centre and perpendicular to its plane. Another disc of same dimensions but of mass $\frac{M}{4}$ is placed gently on the first disc co-axially. The final angular velocity of the system is

Discussion

48.	A boy releases a 0.5 kg ball along the frictionless floor with the speed of 20 m/s. The ball is deflected by an obstacle on the way. After the deflection, it moves with 5% of its initial kinetic energy. What is the final speed of the ball?
Answer» A boy releases a $0.5 kg$ ball along the frictionless floor with the speed of $20 m/s$ . The ball is deflected by an obstacle on the way. After the deflection, it moves with $5 %$ of its initial kinetic energy. What is the final speed of the ball?

Discussion

49.	a particle of mass m moving with speed u collides elastically with a sphere of radius R and same mass ,at rest,at an impact parameter d.find (a) angle between their final velocities and (b)magnitude of their final velocities.
Answer» a particle of mass m moving with speed u collides elastically with a sphere of radius R and same mass ,at rest,at an impact parameter d.find (a) angle between their final velocities and (b)magnitude of their final velocities.

Discussion

50.	A particle moving along the x-axis executes simple harmonic motion, then the force acting on it is given by [CBSE PMT 1994]
Answer» A particle moving along the x-axis executes simple harmonic motion, then the force acting on it is given by [CBSE PMT 1994]

50.

A particle moving along the x-axis executes simple harmonic motion, then the force acting on it is given by [CBSE PMT 1994]

Answer»

A particle moving along the x-axis executes simple harmonic motion, then the force acting on it is given by

[CBSE PMT 1994]

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

The Heights of mercury surface in the two arms of the manometer shown are 2 cm and 8 cm. find the pressure of the gas in the cylinder? Patm = 105 N/m2

An electron having energy 10 eV is circulating in a plane at right angle to a uniform field of magnetic induction 10−4 Wb/m2(=1.0 gauss), the orbital radius of electron is

In mesoscopic physics the laws of macroscopic physics are applicable or not?

A ring oscillator consisting of 3 inverters is running at a frequency of 1 MHz. The value of propagation delay per gate is________nsec. (Answer upto 2 decimal places)71.43

An iron rod of susceptibility 599 is subjected to a magnetizing field of 1200 Am−1. The permeability of the material of the rod is :Take, μ0=4π×10−7 TmA−1

A capacitor has capacitance of 6 nF, maximum voltage it can sustain is 40 volt. It is in series with other capacitor 3 nF and this capacitor can sustain 30 volt, what is maximum voltage that can be applied in series.

two projectiles A and B are thrown from the same point with velocities v and v/2, respectively.if B is thrown at an angle of 45 degree with horizontal, what is the inclination of A when their ranges are the same

Gas in a cylinder is maintained at 10 atm pressure and 300 K temperature. The cylinder will explode if pressure of gas goes beyond 15 atm. What is the maximum temperature to which gas can be heated?

A force 10 N acts tangentially at the highest point of a solid sphere of mass 10 kg kept on a rough horizontal plane. If the sphere rolls without slipping, find the acceleration of the centre of the sphere (in m/s2).

Knowing that mass of Moon is M81 where M is the mass of Earth, find the distance of the point where gravitational field due to Earth and Moon cancel each other, from the Moon, Given that distance between Earth and Moon is 60 R. Where R is the radius of Earth

A photon of wavelength 1 ˚A is completely absorbed by a surface. What is the momentum transferred by this photon?

How many time constants will elapse before the energy stored in the capacitor reaches half of its equilibrium value in a charging RC circuit ?

A fish is moving up vertically with speed 4 cm/s inside a pond. A bird is moving vertically downward (see figure). Velocity of the bird w.r.t. fish is 16 cm/s downward. Find out the actual velocity of the bird (in cm/s). Given refractive index of water is 43.

A body falls from a height h on a horizontal surface and rebounds. Then it falls again and rebounds and so on. If the restitution coefficient is 13, the total distance covered by the body before it comes to rest is

A force of 15 N displaces a box on a horizontal surface through a distance of 10 m. Calculate the angle which the force makes with the direction of motion of the body, if work done is 75 J.

a positively charged pendulum is oscillatinh in a uniform electic field poiting upwards.its time period as compared to that when it oscillates without electic field is.

the refractive indices of a glass prism for violet yellow and red colors are 1.790,1.795 and 1.805 respectively .the dispersive power of the prism

A rod with a linear charge density of 3.5 C/m is 2.5 m long. What is the charge on it?

Photons with energy 5 eV are incident on a cathode C in a photoelectric cell. The maximum energy of emitted photo electrons is 2 eV. When photons of energy 6 eV are incident on C, no photoelectrons will reach the anode A. The stopping potential of A relative to C is

if two identicalspheres hacing charge 16c and -8 c are kept at certain dis†an ce then the force is F they are touched and again kept at same dis†an ce the force becomes

A ball of mass 0.25 kg attached to the ends of a string of length 1.96 m is rotating in a horizontal circle. The string will break, if tension is more than 25 N. What is the maximum velocity with which the ball can be rotated ?

A man standing on a an ice pond want to move on ita)he has to crawl on itb)he has to sneeze and pitc)he can walk easily on itd)he has to roll on it

A series LCR circuit with R=20Ω,L=1.54 H andC=35μF is connected to a variable frequency 200 V ac supply. When the frequency of the supply equals the natural frequency of the circuit. What is the average power in kW transferred to the circuit in one complete cycle?

What is the equivalent resistance between point A and B

A ball of mass 0.1kg and moving with velocity 40 m per second strike up that and returned back in the opposite direction with the same speed. Calculate the change in linear movement of the ball.

In a orthogonal cutting process the tool used has rake angle of zero degree. The measured cutting force and thrust force are 500 N and 250 N, respectively. The coefficient of friction between the tool and the chip is

A metallic block of density 5 gm cm−3 and having dimensions 5 cm × 5 cm × 5 cm is weighed in water. Its apparent weight will be

When a glass rod is rubbed with a silk cloth, charges appear on both. A similar phenomenon is observed with many other pairs ofbodies. Explain how this observation is consistent with the law ofconservation of charge.

143.In the given diagram find the acceleration of the block with respect to the disk

A particle moves in circular path of radius R. If centripetal force F is kept constant but the angular velocity is doubled, the new radius of the path will be

a positive charge q1 is placed at (a,0) and another positive point charge q2 is placed at (0,a) find the force on q1

Why the current flows from negative end to positive end?

An electromagnetic wave travelling through a transparent medium is given by Ex(y,t)=Eoxsin2π[y5×10−7−4×1014t] in SI units. Then what is the refractive index of the medium?

Select the wrong statement about statement :1. Pressure is a scalar quantity. 2. Pressure is always compressive on nature. 3. Pressure at a point is same in all directions. 4. None of these

Unit vector parallel to the resultant of vectors →A=4^i−3^j and →B=8^i+8^j

The electric field associated with an e.m. wave in vacuum is given as →E=40cos(kz−6×108t)^i, where all quantities are in SI units. The value of the propagation constant k is,

Two charges e and 3e are placed at a dis†an ce r. The dis†an ce of the point where the electric field intensity will be zero is

A planet is revolving around the sun in an elliptical orbit. Which of the following remains constant? a.Linear momentum. B.Angular momentum. C.Kinetic energy D.Potential energy.

Voltage rating of a parallel plate capacitor is 500 V. Its dielectric can withstand a maximum electric field of 106 V/m. The plate area is 10−4m2. What is the dielectric constant if the capacitance is 15 pF?(given ϵ0=8.86×10−12 C2/Nm2).

A boy releases a 0.5 kg ball along the frictionless floor with the speed of 20 m/s. The ball is deflected by an obstacle on the way. After the deflection, it moves with 5% of its initial kinetic energy. What is the final speed of the ball?

a particle of mass m moving with speed u collides elastically with a sphere of radius R and same mass ,at rest,at an impact parameter d.find (a) angle between their final velocities and (b)magnitude of their final velocities.

A particle moving along the x-axis executes simple harmonic motion, then the force acting on it is given by [CBSE PMT 1994]