50278 + Interview Questions in Physics Page 283 InterviewSolution

14101.	White light is incident normally on a glass plate (in air) of thickness 500 nm and refractive index ot 1.5. The wavelength (in nm) in the visible region (400 nm-700nm) that is strongly reflected by the plate is what
Answer» White light is incident normally on a glass plate (in air) of thickness 500 nm and refractive index ot 1.5. The wavelength (in nm) in the visible region (400 nm-700nm) that is strongly reflected by the plate is what

Discussion

14102.	A tuning fork produces 4 beats per second, with another tuning fork of frequency 256 Hz. The first one is now loaded with a little wax and the beat frequency is found to increase to 6 per second. The original frequency (in Hz) of the tuning fork was _____.
Answer» A tuning fork produces $4$ beats per second, with another tuning fork of frequency $256 Hz$ . The first one is now loaded with a little wax and the beat frequency is found to increase to $6$ per second. The original frequency $(in Hz)$ of the tuning fork was _____.

Discussion

14103.	if value of acceleration due to gravity at a place dec by 3% then find the height of mercury in a barometer at that plac
Answer» if value of acceleration due to gravity at a place dec by 3% then find the height of mercury in a barometer at that plac

Discussion

14104.	The y-component of a velocity is v m/s and x-component of velocity is root3v m/s. The direction of the body with the y-axis at this instant is
Answer» The y-component of a velocity is v m/s and x-component of velocity is root3v m/s. The direction of the body with the y-axis at this instant is

Discussion

14105.	A projectile is thrown from a point in a horizontal place such that its horizontal and vertical velocity component are 9.8 m/s and 19.6 m/s respectively. Its horizontal range is
Answer» A projectile is thrown from a point in a horizontal place such that its horizontal and vertical velocity component are 9.8 m/s and 19.6 m/s respectively. Its horizontal range is

Discussion

14106.	a solid sphere of mass m is rolling with speed v on a horizontal surface and strikes a massless spring of forces cons†an t k then the maximum compression in the spring is?
Answer» a solid sphere of mass m is rolling with speed v on a horizontal surface and strikes a massless spring of forces cons†an t k then the maximum compression in the spring is?

Discussion

14107.	A hemispherical portion of radius 4 cm is removed from the bottom of a cylinder of radius 4 cm. The volume of remaining cylinder is 128π cm3 and it is suspended by a string in a liquid of density 0.8 g/cm3 where it stays vertical. The upper surface of the cylinder is at a depth 2 cm below the liquid surface. The force on the bottom of the cylinder by the liquid is (g is the acceleration due to gravity)
Answer» A hemispherical portion of radius $4 cm$ is removed from the bottom of a cylinder of radius $4 cm$ . The volume of remaining cylinder is $128 π {cm}^{3}$ and it is suspended by a string in a liquid of density $0.8 {g/cm}^{3}$ where it stays vertical. The upper surface of the cylinder is at a depth $2 cm$ below the liquid surface. The force on the bottom of the cylinder by the liquid is ( $g$ is the acceleration due to gravity)

Discussion

14108.	A stone is dropped into a quite lake and waves motion in circles at speed of 5 cm/s at the instant when the radius of the circular wave is 8cm .how fast is the enclosed area increasing
Answer» A stone is dropped into a quite lake and waves motion in circles at speed of 5 cm/s at the instant when the radius of the circular wave is 8cm .how fast is the enclosed area increasing

Discussion

14109.	Energy per unit volume for a capacitor having area A and separation d kept at potential difference V is given by
Answer» Energy per unit volume for a capacitor having area $A$ and separation $d$ kept at potential difference $V$ is given by

Discussion

14110.	A box when dropped from a certain height reaches the ground with a speed v. When it skids from rest from the same height down a rough inclined plane inclined at an angle 45∘ to the horizontal, it reaches the ground with a speed v3. The coefficient of sliding friction between the box and the plane is (acceleration due to gravity is 10ms−2 )
Answer» A box when dropped from a certain height reaches the ground with a speed $v$ . When it skids from rest from the same height down a rough inclined plane inclined at an angle $45^{\circ}$ to the horizontal, it reaches the ground with a speed $\frac{v}{3}$ . The coefficient of sliding friction between the box and the plane is (acceleration due to gravity is $10 m s^{- 2}$ )

Discussion

14111.	Explain why (a) To keep a piece of paper horizontal, you should blow over, not under, it (b) When we try to close a water tap with our fingers, fast jets of water gush through the openings between our fingers (c) The size of the needle of a syringe controls flow rate better than the thumb pressure exerted by a doctor while administering an injection (d) A fluid flowing out of a small hole in a vessel results in a backward thrust on the vessel (e) A spinning cricket ball in air does not follow a parabolic trajectory
Answer» Explain why (a) To keep a piece of paper horizontal, you should blow over, not under, it (b) When we try to close a water tap with our fingers, fast jets of water gush through the openings between our fingers (c) The size of the needle of a syringe controls flow rate better than the thumb pressure exerted by a doctor while administering an injection (d) A fluid flowing out of a small hole in a vessel results in a backward thrust on the vessel (e) A spinning cricket ball in air does not follow a parabolic trajectory

Discussion

14112.	A rod of mass m and length 2l hangs by two identical light threads tied to its ends. An insect of mass 3m8 lands on the rod gently at a distance l3 from the centre of the rod as shown and sticks to it. As a result one of the thread breaks. The acceleration of the insect just after the thread breaks given that the insect remains at rest with respect to the rod.
Answer» A rod of mass $m$ and length $2 l$ hangs by two identical light threads tied to its ends. An insect of mass $\frac{3 m}{8}$ lands on the rod gently at a distance $\frac{l}{3}$ from the centre of the rod as shown and sticks to it. As a result one of the thread breaks. The acceleration of the insect just after the thread breaks given that the insect remains at rest with respect to the rod.

Discussion

14113.	Why does electric lines as well as magnetic line do not intersect ? And why magnetic field line do not form a closed loop
Answer» Why does electric lines as well as magnetic line do not intersect ? And why magnetic field line do not form a closed loop

Discussion

14114.	The macroscopic properties of gases include its pressure (P), volume (V), its temperature (T), the quantity of the gas, which can be measured by its mass (M), or the number of gas particles (atoms/molecules; N). One of the earliest investigations on a relationship between these properties was conducted by Robert Boyle, chiefly motivated by a hunch against one of his contemporary, Toricelli's claim on how a barometer works. Boyle's set-up was as shown.He attached a small U-tube at the end of a Toricellian tube and powered in mercury from the open end (T); as mercury rose in the closed, shorter column, the trapped air would get more and move compressed - which could only mean, that the pressure increased, and the volume decreased (these were respectively measured by the height of the mercury column, h, and a scale on the shorter column, V, for volume of the trapped air).Which of these statements is/are correct in regard to Boyle's conclusion from the data?
Answer» The macroscopic properties of gases include its pressure (P), volume (V), its temperature (T), the quantity of the gas, which can be measured by its mass (M), or the number of gas particles (atoms/molecules; N). One of the earliest investigations on a relationship between these properties was conducted by Robert Boyle, chiefly motivated by a hunch against one of his contemporary, Toricelli's claim on how a barometer works. Boyle's set-up was as shown. He attached a small U-tube at the end of a Toricellian tube and powered in mercury from the open end (T); as mercury rose in the closed, shorter column, the trapped air would get more and move compressed - which could only mean, that the pressure increased, and the volume decreased (these were respectively measured by the height of the mercury column, h, and a scale on the shorter column, V, for volume of the trapped air). Which of these statements is/are correct in regard to Boyle's conclusion from the data?

Discussion

14115.	A uniform electric field pointing in positive x-direction exists in a region. Let A be the origin, B be the point on the x-axis at x = +1 cm and C be the point on the y-axis at y = +1 cm. Then the potentials at the points A, B and C satisfy:
Answer» A uniform electric field pointing in positive x-direction exists in a region. Let A be the origin, B be the point on the x-axis at x = +1 cm and C be the point on the y-axis at y = +1 cm. Then the potentials at the points A, B and C satisfy:

Discussion

14116.	A body is projected vertically upward . if t1 and t2 be the times at which it is at height h above the point of projection while ascending and descending . what is the height h and the velocity of projection ?
Answer» A body is projected vertically upward . if t1 and t2 be the times at which it is at height h above the point of projection while ascending and descending . what is the height h and the velocity of projection ?

Discussion

14117.	The acceleration due to gravity ___ as you go downwards
Answer» The acceleration due to gravity ___ as you go downwards

Discussion

14118.	A solid cylinder attached to horizontal massless spring can roll without slipping along horizontal surface. Find time period of oscillation.
Answer» A solid cylinder attached to horizontal massless spring can roll without slipping along horizontal surface. Find time period of oscillation.

Discussion

14119.	the nernst equation indicates that the equilibrium cons†an t K_c will be equal to Q when E^ocell =0 how?
Answer» the nernst equation indicates that the equilibrium cons†an t K_c will be equal to Q when E^ocell =0 how?

Discussion

14120.	The speed of cyclist is 10m/s and speed of wind is 4m/s.can the speed of wind relative to the speed of cyclist be 10m/m?
Answer» The speed of cyclist is 10m/s and speed of wind is 4m/s.can the speed of wind relative to the speed of cyclist be 10m/m?

Discussion

14121.	In which of the graph, the particle has more magnitude of velocity at t1 than at t2.
Answer» In which of the graph, the particle has more magnitude of velocity at $t_{1}$ than at $t_{2}$ .

14121.

In which of the graph, the particle has more magnitude of velocity at t1 than at t2.

Answer»

In which of the graph, the particle has more magnitude of velocity at $t_{1}$ than at $t_{2}$ .

Discussion

14122.	Reverse breakdown voltage for Zener diode series is 3.2 V, Find the current (i) through Zener diode.
Answer» Reverse breakdown voltage for Zener diode series is $3.2 V$ , Find the current $(i)$ through Zener diode.

Discussion

14123.	What must be the charge on each of two 100kg spherical masses in order for the electrical force to be equal to the gravitational force?
Answer» What must be the charge on each of two 100kg spherical masses in order for the electrical force to be equal to the gravitational force?

Discussion

14124.	Two identical spheres with charge Q exert a force F on each other. The spheres are kept fixed with a distance r between them. A third identical but uncharged sphere C is brought in contact with A and then placed at the mid point of the line joining A & B. The magnitude of net electric force on C is
Answer» Two identical spheres with charge $Q$ exert a force $F$ on each other. The spheres are kept fixed with a distance $r$ between them. A third identical but uncharged sphere C is brought in contact with A and then placed at the mid point of the line joining A & B. The magnitude of net electric force on C is

Discussion

14125.	A wheel of radius 0.5m is spinning with a constant angular velocity of 2rad/sec what is the centripetal acceleration of a point on the wheel's rim?
Answer» A wheel of radius 0.5m is spinning with a constant angular velocity of 2rad/sec what is the centripetal acceleration of a point on the wheel's rim?

Discussion

14126.	Dimensions of strain are
Answer» Dimensions of strain are

Discussion

14127.	The acceleration of the particle moving in positive x−direction with an initial velocity of 10 m/s is 3 m/s2. Its velocity at t=4 sec is
Answer» The acceleration of the particle moving in positive $x -$ direction with an initial velocity of $10 m / s$ is $3 m / s^{2}$ . Its velocity at $t = 4 s e c$ is

Discussion

14128.	Three particles each having a charge of 10μ C, are placed at the vertices of an equilateral triangle of side 10cm . Find the work done by a person in pulling them apart to infinite separartions
Answer» Three particles each having a charge of 10μ C, are placed at the vertices of an equilateral triangle of side 10cm . Find the work done by a person in pulling them apart to infinite separartions

Discussion

14129.	A cinema hall has equidistant rows 1 m apart. The length of the cinema hall is 287 m and it has 287 rows. From one side of the cinema hall, laughing gas (N2O) is released and from the other side, tear gas (C6H5COCH2Cl) is released. In which rows, spectators will be laughing and weeping simultaneously?
Answer» A cinema hall has equidistant rows $1$ m apart. The length of the cinema hall is $287$ m and it has $287$ rows. From one side of the cinema hall, laughing gas $(N_{2} O)$ is released and from the other side, tear gas $(C_{6} H_{5} C O C H_{2} C l)$ is released. In which rows, spectators will be laughing and weeping simultaneously?

14129.

A cinema hall has equidistant rows 1 m apart. The length of the cinema hall is 287 m and it has 287 rows. From one side of the cinema hall, laughing gas (N2O) is released and from the other side, tear gas (C6H5COCH2Cl) is released. In which rows, spectators will be laughing and weeping simultaneously?

Answer»

A cinema hall has equidistant rows $1$ m apart. The length of the cinema hall is $287$ m and it has $287$ rows. From one side of the cinema hall, laughing gas $(N_{2} O)$ is released and from the other side, tear gas $(C_{6} H_{5} C O C H_{2} C l)$ is released. In which rows, spectators will be laughing and weeping simultaneously?

Discussion

14130.	two blocks of masses 1kg and 2kg are connected with massless spring as shown if the acceleration of 1kg block is1m/s^2 toward right then the acceleration of 2kg block is
Answer» two blocks of masses 1kg and 2kg are connected with massless spring as shown if the acceleration of 1kg block is1m/s^2 toward right then the acceleration of 2kg block is

Discussion

14131.	A pendulum clock that work fines on earth is placed on the moon. How many times the clock would tick in an actual time of 30 seconds? Given object weighs one sixth on moon as much as on earth.
Answer» A pendulum clock that work fines on earth is placed on the moon. How many times the clock would tick in an actual time of 30 seconds? Given object weighs one sixth on moon as much as on earth.

Discussion

14132.	∫sin2xsin3x(dx)=
Answer» $\int \frac{sin 2 x}{sin 3 x} (d x) =$

Discussion

14133.	An 8-bit counter type ADC has worst case conversion time equal to 0 times of that of an 8-bit successive approximation type ADC, if AND gate of counter type ADC is clocked with a 5MHz clock signal. This conversation time is used for an analog input of 2V of SAC type ADC. Then conversation time for a 4V input will be
Answer» An 8-bit counter type ADC has worst case conversion time equal to 0 times of that of an 8-bit successive approximation type ADC, if AND gate of counter type ADC is clocked with a $5 M H z$ clock signal. This conversation time is used for an analog input of $2 V$ of SAC type ADC. Then conversation time for a $4 V$ input will be

Discussion

14134.	A disc of moment of inertia 9.8π2 kgm2 is rotating at 600 rpm. If the frequency of rotation changes from 600 rpm to 300 rpm, then what is the work done.
Answer» A disc of moment of inertia $\frac{9.8}{π^{2}} {kgm}^{2}$ is rotating at $600 rpm$ . If the frequency of rotation changes from $600 rpm$ to $300 rpm$ , then what is the work done.

Discussion

14135.	A particle of mass 2kg travelling in straight line with velocity v=\sqrt x where a is cons†an t.the work done by net force during displacement from x=0 to x=4m is?
Answer» A particle of mass 2kg travelling in straight line with velocity v=\sqrt x where a is cons†an t.the work done by net force during displacement from x=0 to x=4m is?

Discussion

14136.	The total flux over a closed surface enclosing the charges q
Answer» The total flux over a closed surface enclosing the charges q

Discussion

14137.	Three identical capacitors C1,C2 and C3 have a capacitance of 1.0 μF each and they are uncharged initially. They are connected in a circuit as shown in the figure and C1 is then filled completely with a dielectric material of relative permittivity ∈r. The cell electromotive force (emf) Vo=8 V. First, the switch S1 is closed while the switch S2 is kept open. When the capacitor C3 is fully charged, S1 is opened and S2 is closed simultaneously. When all the capacitors reach equilibrium, the charge on C3 is found to be 5 μC. The value of ∈r is
Answer» Three identical capacitors $C_{1}, C_{2}$ and $C_{3}$ have a capacitance of $1.0 μ F$ each and they are uncharged initially. They are connected in a circuit as shown in the figure and $C_{1}$ is then filled completely with a dielectric material of relative permittivity $\in_{r}$ . The cell electromotive force (emf) $V_{o} = 8 V$ . First, the switch $S_{1}$ is closed while the switch $S_{2}$ is kept open. When the capacitor $C_{3}$ is fully charged, $S_{1}$ is opened and $S_{2}$ is closed simultaneously. When all the capacitors reach equilibrium, the charge on $C_{3}$ is found to be $5 μ C$ . The value of $\in_{r}$ is

Discussion

14138.	32. Find the degree measures corresponding to the following radiant measure (Use = 22/7) 1). 11/16 2). -4
Answer» 32. Find the degree measures corresponding to the following radiant measure (Use = 22/7) 1). 11/16 2). -4

Discussion

14139.	In millikan's oil drop experiment how did the droplets acquired the charge ? What was the gas present in between two metal plates .....
Answer» In millikan's oil drop experiment how did the droplets acquired the charge ? What was the gas present in between two metal plates .....

Discussion

14140.	The specific heat of a gas is found to be0.075 calories at constant volume and its formulawt is 40. The atomicity of the gas would be(1) One(2) Two(4) Four3) Three
Answer» The specific heat of a gas is found to be0.075 calories at constant volume and its formulawt is 40. The atomicity of the gas would be(1) One(2) Two(4) Four3) Three

Discussion

14141.	The current in a conductor varies with time t as I=3t+4t2, where I is in amperes and t in seconds. The electric charge that flows through the section of the conductor between t = 1 s and t = 3 s is
Answer» The current in a conductor varies with time t as $I = 3 t + 4 t^{2}$ , where I is in amperes and t in seconds. The electric charge that flows through the section of the conductor between t = 1 s and t = 3 s is

Discussion

14142.	the linear charge density upon the semi circular ring on both side is same in magnitude the electric field at O is alon
Answer» the linear charge density upon the semi circular ring on both side is same in magnitude the electric field at O is alon

Discussion

14143.	Four bodies each of mass m are placed at different corners of a square of side a. Find work done on the system to take any one body to infinity.
Answer» Four bodies each of mass m are placed at different corners of a square of side a. Find work done on the system to take any one body to infinity.

Discussion

14144.	A uniform copper wire of length 1 m and cross-sectional area 5×10−7 m2 carries current of 1 A. Assuming that there are 8×1028 free electron per m3 in copper, how long will an electron take to drift from one end of the wire to the other ?
Answer» A uniform copper wire of length $1 m$ and cross-sectional area $5 \times 10^{- 7} m^{2}$ carries current of $1 A$ . Assuming that there are $8 \times 10^{28}$ free electron per $m^{3}$ in copper, how long will an electron take to drift from one end of the wire to the other ?

Discussion

14145.	a body moving with uniform retardation covers 3Km before its speed is reduced to half of its initial value . it comes to rest in another dis†an ce o
Answer» a body moving with uniform retardation covers 3Km before its speed is reduced to half of its initial value . it comes to rest in another dis†an ce o

Discussion

14146.	The work functions of Silver and Sodium are 4.6 and 2.3 eV, respectively. The ratio of the slope of the stopping potential versus frequency plot for Silver to that of Sodium is
Answer» The work functions of Silver and Sodium are 4.6 and 2.3 eV, respectively. The ratio of the slope of the stopping potential versus frequency plot for Silver to that of Sodium is

Discussion

14147.	A circular loop of radius r is bent along a diameter and given a shape as shown in the figure. One of the semicircles lies in xz−plane and the other one in yz−plane, with their centres at origin. The same current I flows through each of the semicircles as shown. The net magnetic field at the origin is,
Answer» A circular loop of radius $r$ is bent along a diameter and given a shape as shown in the figure. One of the semicircles lies in $x z -$ plane and the other one in $y z -$ plane, with their centres at origin. The same current $I$ flows through each of the semicircles as shown. The net magnetic field at the origin is,

Discussion

14148.	If a particle has velocity v(t)=4t+2 m/s, the average speed in 2 sec is
Answer» If a particle has velocity $v (t) = 4 t + 2 m/s$ , the average speed in $2 sec$ is

Discussion

14149.	6. Two line A and B in the plot given below shows the variation of de- Broglie wavelength lambda vs \sqrt{}v ,where v is the accelerating potential for two particles carrying same charge.Which one of the two represents a particle of smaller mass?
Answer» 6. Two line A and B in the plot given below shows the variation of de- Broglie wavelength lambda vs \sqrt{}v ,where v is the accelerating potential for two particles carrying same charge.Which one of the two represents a particle of smaller mass?

Discussion

14150.	cubical block of side a and mass m rests on a rough horizontal surface. a horizontal force f is applied to normal to one of the faces a height h above the base h is greater than a /2 . the minimum value of a force f for which the cube begins to topple about an edge
Answer» cubical block of side a and mass m rests on a rough horizontal surface. a horizontal force f is applied to normal to one of the faces a height h above the base h is greater than a /2 . the minimum value of a force f for which the cube begins to topple about an edge

Discussion

Explore topic-wise InterviewSolutions in .

White light is incident normally on a glass plate (in air) of thickness 500 nm and refractive index ot 1.5. The wavelength (in nm) in the visible region (400 nm-700nm) that is strongly reflected by the plate is what

A tuning fork produces 4 beats per second, with another tuning fork of frequency 256 Hz. The first one is now loaded with a little wax and the beat frequency is found to increase to 6 per second. The original frequency (in Hz) of the tuning fork was _____.

if value of acceleration due to gravity at a place dec by 3% then find the height of mercury in a barometer at that plac

The y-component of a velocity is v m/s and x-component of velocity is root3v m/s. The direction of the body with the y-axis at this instant is

A projectile is thrown from a point in a horizontal place such that its horizontal and vertical velocity component are 9.8 m/s and 19.6 m/s respectively. Its horizontal range is

a solid sphere of mass m is rolling with speed v on a horizontal surface and strikes a massless spring of forces cons†an t k then the maximum compression in the spring is?

A stone is dropped into a quite lake and waves motion in circles at speed of 5 cm/s at the instant when the radius of the circular wave is 8cm .how fast is the enclosed area increasing

Energy per unit volume for a capacitor having area A and separation d kept at potential difference V is given by

Why does electric lines as well as magnetic line do not intersect ? And why magnetic field line do not form a closed loop

A uniform electric field pointing in positive x-direction exists in a region. Let A be the origin, B be the point on the x-axis at x = +1 cm and C be the point on the y-axis at y = +1 cm. Then the potentials at the points A, B and C satisfy:

A body is projected vertically upward . if t1 and t2 be the times at which it is at height h above the point of projection while ascending and descending . what is the height h and the velocity of projection ?

The acceleration due to gravity ___ as you go downwards

A solid cylinder attached to horizontal massless spring can roll without slipping along horizontal surface. Find time period of oscillation.

the nernst equation indicates that the equilibrium cons†an t K_c will be equal to Q when E^ocell =0 how?

The speed of cyclist is 10m/s and speed of wind is 4m/s.can the speed of wind relative to the speed of cyclist be 10m/m?

In which of the graph, the particle has more magnitude of velocity at t1 than at t2.

Reverse breakdown voltage for Zener diode series is 3.2 V, Find the current (i) through Zener diode.

What must be the charge on each of two 100kg spherical masses in order for the electrical force to be equal to the gravitational force?

A wheel of radius 0.5m is spinning with a constant angular velocity of 2rad/sec what is the centripetal acceleration of a point on the wheel's rim?

Dimensions of strain are

The acceleration of the particle moving in positive x−direction with an initial velocity of 10 m/s is 3 m/s2. Its velocity at t=4 sec is

Three particles each having a charge of 10μ C, are placed at the vertices of an equilateral triangle of side 10cm . Find the work done by a person in pulling them apart to infinite separartions

two blocks of masses 1kg and 2kg are connected with massless spring as shown if the acceleration of 1kg block is1m/s^2 toward right then the acceleration of 2kg block is

A pendulum clock that work fines on earth is placed on the moon. How many times the clock would tick in an actual time of 30 seconds? Given object weighs one sixth on moon as much as on earth.

∫sin2xsin3x(dx)=

A disc of moment of inertia 9.8π2 kgm2 is rotating at 600 rpm. If the frequency of rotation changes from 600 rpm to 300 rpm, then what is the work done.

A particle of mass 2kg travelling in straight line with velocity v=\sqrt x where a is cons†an t.the work done by net force during displacement from x=0 to x=4m is?

The total flux over a closed surface enclosing the charges q

32. Find the degree measures corresponding to the following radiant measure (Use = 22/7) 1). 11/16 2). -4

In millikan's oil drop experiment how did the droplets acquired the charge ? What was the gas present in between two metal plates .....

The specific heat of a gas is found to be0.075 calories at constant volume and its formulawt is 40. The atomicity of the gas would be(1) One(2) Two(4) Four3) Three

The current in a conductor varies with time t as I=3t+4t2, where I is in amperes and t in seconds. The electric charge that flows through the section of the conductor between t = 1 s and t = 3 s is

the linear charge density upon the semi circular ring on both side is same in magnitude the electric field at O is alon

Four bodies each of mass m are placed at different corners of a square of side a. Find work done on the system to take any one body to infinity.

A uniform copper wire of length 1 m and cross-sectional area 5×10−7 m2 carries current of 1 A. Assuming that there are 8×1028 free electron per m3 in copper, how long will an electron take to drift from one end of the wire to the other ?

a body moving with uniform retardation covers 3Km before its speed is reduced to half of its initial value . it comes to rest in another dis†an ce o

The work functions of Silver and Sodium are 4.6 and 2.3 eV, respectively. The ratio of the slope of the stopping potential versus frequency plot for Silver to that of Sodium is

If a particle has velocity v(t)=4t+2 m/s, the average speed in 2 sec is

6. Two line A and B in the plot given below shows the variation of de- Broglie wavelength lambda vs \sqrt{}v ,where v is the accelerating potential for two particles carrying same charge.Which one of the two represents a particle of smaller mass?

cubical block of side a and mass m rests on a rough horizontal surface. a horizontal force f is applied to normal to one of the faces a height h above the base h is greater than a /2 . the minimum value of a force f for which the cube begins to topple about an edge