50278 + Interview Questions in Physics

1.	Two point charges q1=q2=+2 μC are fixed at x1=+3 m and x2=−3 m as shown in the figure. A third particle of mass 1 g and charge q3=−4 μC is released from rest at y=4 m. Find the speed of the third particle as it reaches the origin.
Answer» Two point charges $q_{1} = q_{2} = + 2 μ C$ are fixed at $x_{1} = + 3 m$ and $x_{2} = - 3 m$ as shown in the figure. A third particle of mass $1 g$ and charge $q_{3} = - 4 μ C$ is released from rest at $y = 4 m$ . Find the speed of the third particle as it reaches the origin.

Discussion

2.	Thepotential energy function for a particle executing linear simpleharmonic motion is given by V(x)=kx2/2,where kis the force constant of theoscillator. For k= 0.5 N m–1,the graph of V(x)versus xis shown in Fig. 6.12. Show thata particle of total energy 1 J moving under this potential must ‘turnback’ when it reaches x= ± 2 m.
Answer» The potential energy function for a particle executing linear simple harmonic motion is given by V(x) =kx²/2, where k is the force constant of the oscillator. For k = 0.5 N m^–1, the graph of V(x) versus x is shown in Fig. 6.12. Show that a particle of total energy 1 J moving under this potential must ‘turn back’ when it reaches x = ± 2 m.

2.

Thepotential energy function for a particle executing linear simpleharmonic motion is given by V(x)=kx2/2,where kis the force constant of theoscillator. For k= 0.5 N m–1,the graph of V(x)versus xis shown in Fig. 6.12. Show thata particle of total energy 1 J moving under this potential must ‘turnback’ when it reaches x= ± 2 m.

Answer»

The
potential energy function for a particle executing linear simple
harmonic motion is given by V(x)
=kx²/2,
where k
is the force constant of the
oscillator. For k
= 0.5 N m^–1,
the graph of V(x)
versus x
is shown in Fig. 6.12. Show that
a particle of total energy 1 J moving under this potential must ‘turn
back’ when it reaches x
= ± 2 m.

Discussion

3.	The speed of a projectile when it is at its maximum height is √25 times its speed at half the maximum height. The angle of projection is
Answer» The speed of a projectile when it is at its maximum height is $\sqrt{\frac{2}{5}}$ times its speed at half the maximum height. The angle of projection is

Discussion

4.	Raindrops of radius 1 mm and mass 4 mg are falling with a speed of 30 m/s on the head and come to rest.Assuming equivalently that the drops cover a dis†an ce equal to their radii on the head,estimate the force exerted by each drop on the head.
Answer» Raindrops of radius 1 mm and mass 4 mg are falling with a speed of 30 m/s on the head and come to rest.Assuming equivalently that the drops cover a dis†an ce equal to their radii on the head,estimate the force exerted by each drop on the head.

Discussion

5.	A point source of light is arranged at a height h above the surface of water. Where will the image of this source in the flat mirror like bottom of a vessel be if depth of the vessel full of water is d?Refractive index of water is n=4/3. Consider only two steps.
Answer» A point source of light is arranged at a height h above the surface of water. Where will the image of this source in the flat mirror like bottom of a vessel be if depth of the vessel full of water is d?Refractive index of water is n=4/3. Consider only two steps.

Discussion

6.	Why ammeter is connected in series and voltmeter in parallel
Answer» Why ammeter is connected in series and voltmeter in parallel

Discussion

7.	A converging becam of light forms a sharp image on a screen. A lens is placed in the path of the beam, at 10 cm from the screen, it is found that the screen has to be moved 8 cm further away from the lens to obtam a sharp image. The focal length and the nature of lens is.
Answer» A converging becam of light forms a sharp image on a screen. A lens is placed in the path of the beam, at $10 cm$ from the screen, it is found that the screen has to be moved $8 cm$ further away from the lens to obtam a sharp image. The focal length and the nature of lens is.

Discussion

8.	Four unchanged capacitors C1,C2,C3 and C4 are connected as shown in the figure. The point A, B, C and D are kept at potential V1,V2,V3 and V4 respectively. Then the potential V0 at point O is
Answer» Four unchanged capacitors $C_{1}, C_{2}, C_{3} and C_{4}$ are connected as shown in the figure. The point $A, B, C and D$ are kept at potential $V_{1}, V_{2}, V_{3} and V_{4}$ respectively. Then the potential $V_{0}$ at point $O$ is

Discussion

9.	11. If a particle of mass m is moving with constant velocity vparallel to x-axis in x-y plane as shown in fig. Its angularmomentum with respect to origin at any time t will be[MP PET 2011](a) mubk(b)-mub k(c) mubi(d) muiVector A has a magnitidlet
Answer» 11. If a particle of mass m is moving with constant velocity v parallel to x-axis in x-y plane as shown in fig. Its angular momentum with respect to origin at any time t will be [MP PET 2011] (a) mubk (b)-mub k (c) mubi (d) mui Vector A has a magnitidlet

Discussion

10.	A block of mass m slides down an inclined plane of inclination θ with uniform speed. The coefficient of friction between the block and the plane is μ. The contact force between the block and the plane is
Answer» A block of mass $m$ slides down an inclined plane of inclination $θ$ with uniform speed. The coefficient of friction between the block and the plane is $μ$ . The contact force between the block and the plane is

Discussion

11.	A particle moves along a circular path over a horizontal xy coordinate system, at constant speed. At time t1 = 5.00 s, it is at point (5.00 m, 6.00 m) with velocity (3π m/s)^j and acceleration in the positive x direction. At time t2 = 10.0 s, it has velocity (-3π m/s)^i and acceleration in the positive y direction. What are the (a) x and (b) y coordinates of the center of the circular path if t2 - t1 is less than one period?
Answer» A particle moves along a circular path over a horizontal xy coordinate system, at constant speed. At time t₁ = 5.00 s, it is at point (5.00 m, 6.00 m) with velocity (3π m/s) $^j$ and acceleration in the positive x direction. At time t₂ = 10.0 s, it has velocity (-3π m/s) $^i$ and acceleration in the positive y direction. What are the (a) x and (b) y coordinates of the center of the circular path if t₂ - t₁ is less than one period?

11.

A particle moves along a circular path over a horizontal xy coordinate system, at constant speed. At time t1 = 5.00 s, it is at point (5.00 m, 6.00 m) with velocity (3π m/s)^j and acceleration in the positive x direction. At time t2 = 10.0 s, it has velocity (-3π m/s)^i and acceleration in the positive y direction. What are the (a) x and (b) y coordinates of the center of the circular path if t2 - t1 is less than one period?

Answer»

A particle moves along a circular path over a horizontal xy coordinate system, at constant speed. At time t₁ = 5.00 s, it is at point (5.00 m, 6.00 m) with velocity (3π m/s) $^j$ and acceleration in the positive x direction. At time t₂ = 10.0 s, it has velocity (-3π m/s) $^i$ and acceleration in the positive y direction. What are the (a) x and (b) y coordinates of the center of the circular path if t₂ - t₁ is less than one period?

Discussion

12.	(a) Draw the circuit diagram of an n-p-n transistor amplifer in common emitter configuration. (b) Derive an experssion for voltage gain of the amplifier and hence show that the output voltage is in opposite phase with the input voltage.
Answer» (a) Draw the circuit diagram of an n-p-n transistor amplifer in common emitter configuration. (b) Derive an experssion for voltage gain of the amplifier and hence show that the output voltage is in opposite phase with the input voltage.

Discussion

13.	A vehicle traveling at a speed of 30 m/ s is accelerated to a velocity of 60 m/ s if the mass of the vehicle is 90 kg and each wheel weights 250 g. Calculate the change in kinetic energy of the vehicle
Answer» A vehicle traveling at a speed of 30 m/ s is accelerated to a velocity of 60 m/ s if the mass of the vehicle is 90 kg and each wheel weights 250 g. Calculate the change in kinetic energy of the vehicle

Discussion

14.	When a system is taken through the process abc shown in the figure, 90 J of heat is absorbed by the system and 40 J of work is done by it. If the system does 30 J of work during the process adc, how much heat flows into it during the process?
Answer» When a system is taken through the process $a b c$ shown in the figure, $90 J$ of heat is absorbed by the system and $40 J$ of work is done by it. If the system does $30 J$ of work during the process $a d c$ , how much heat flows into it during the process?

Discussion

15.	What is the conductivity of a semiconductor sample having electron concentration of 510 raised power 18 m per cube, hole concentation of 510 raised power 19 m per cube, electron mobility of 2.0m per square/V/s and hole mobility of 0.01 m square/ V /s?
Answer» What is the conductivity of a semiconductor sample having electron concentration of 510 raised power 18 m per cube, hole concentation of 510 raised power 19 m per cube, electron mobility of 2.0m per square/V/s and hole mobility of 0.01 m square/ V /s?

Discussion

16.	1000cells are connected in series and int resistances are in series then what is the drop in the potential in 399 cell
Answer» 1000cells are connected in series and int resistances are in series then what is the drop in the potential in 399 cell

Discussion

17.	A sound signal is sent through a composite tube as shown in the figure. The radius of the semicircle is R and speed of sound in air is v. If 'n' is an integer, then the frequencies of the signal for obtaining maximum value of intensity are given by
Answer» A sound signal is sent through a composite tube as shown in the figure. The radius of the semicircle is $R$ and speed of sound in air is $v$ . If ' $n$ ' is an integer, then the frequencies of the signal for obtaining maximum value of intensity are given by

Discussion

18.	A circular coil has moment of inertia 0.8 kg m2 around any diameter and is carrying current to produce a magnetic moment of 20 Am2. The coil is kept initially in a vertical position, and it can rotate freely around a horizontal diameter. When a uniform magnetic field of 4 T is applied along the vertical, it starts rotating around its horizontal diameter. The angular speed the coil, acquired after rotating by 60∘, will be :
Answer» A circular coil has moment of inertia $0.8 {kg m}^{2}$ around any diameter and is carrying current to produce a magnetic moment of $20 {Am}^{2}$ . The coil is kept initially in a vertical position, and it can rotate freely around a horizontal diameter. When a uniform magnetic field of $4 T$ is applied along the vertical, it starts rotating around its horizontal diameter. The angular speed the coil, acquired after rotating by $60^{\circ}$ , will be :

Discussion

19.	15.A bar magnet of magnetic moment M is bent in the U shape such that all parts are of equal lengths. Then the new magnetic moment is
Answer» 15.A bar magnet of magnetic moment M is bent in the U shape such that all parts are of equal lengths. Then the new magnetic moment is

Discussion

20.	ntA particle ismoving in x-y plane in a circular path with centre at origin . If at an instant the position of particle is given by [1/root of 2 ](i+j), the velocity of particle is along ?n
Answer» ntA particle ismoving in x-y plane in a circular path with centre at origin . If at an instant the position of particle is given by [1/root of 2 ](i+j), the velocity of particle is along ?n

Discussion

21.	A charged ball of mass 900 g is suspended from a string in a uniform electric field →E=(3^i+5^j)×105 N/C. The ball is in equilibrium with θ=37∘. If the direction of electric field is reversed, find the new equilibrium position of the ball. Give your answer in terms of angle made by string with vertical. Take g=10 m/s2
Answer» A charged ball of mass $900 g$ is suspended from a string in a uniform electric field $\to E = (3^i + 5^j) \times 10^{5} N/C$ . The ball is in equilibrium with $θ = 37^{\circ}$ . If the direction of electric field is reversed, find the new equilibrium position of the ball. Give your answer in terms of angle made by string with vertical. Take $g = 10 {m/s}^{2}$

Discussion

22.	Three very large plates of same area are kept parallel and close to each other. They are considered as ideal black surfaces and have very high thermal conductivity. The first and third plates are maintained at temperatures 2T and 3T respectively. The temperature of the middle (i.e. second) plate under steady state condition is
Answer» Three very large plates of same area are kept parallel and close to each other. They are considered as ideal black surfaces and have very high thermal conductivity. The first and third plates are maintained at temperatures $2 T$ and $3 T$ respectively. The temperature of the middle (i.e. second) plate under steady state condition is

Discussion

23.	For an oscillating pendulum does the tension of string remains same or changes?
Answer» For an oscillating pendulum does the tension of string remains same or changes?

Discussion

24.	(a) Write three characteristic properties of nuclear force. (b) Draw a plot of potential energy of a pair of nucleons as a function of their separation. Write two important conclusions that can be drawn from the graph.
Answer» (a) Write three characteristic properties of nuclear force. (b) Draw a plot of potential energy of a pair of nucleons as a function of their separation. Write two important conclusions that can be drawn from the graph.

Discussion

25.	If we can throw a ball upto a maximum height H, the maximum horizontal distance to which we can throw it is
Answer» If we can throw a ball upto a maximum height $H$ , the maximum horizontal distance to which we can throw it is

Discussion

26.	Find derivative of f(x)=elnx+sinx+8
Answer» Find derivative of $f (x) = e^{ln x} + sin x + 8$

Discussion

27.	there are two object of mass 20kg and 300kg. let m_1=20kg and m_2=300kg. what is the acceleration by which object of mass 20kg will be attracted to the mass of 300kg. also find the acceleration by which 300kg mass will be attracted towqrds 20kg
Answer» there are two object of mass 20kg and 300kg. let m_1=20kg and m_2=300kg. what is the acceleration by which object of mass 20kg will be attracted to the mass of 300kg. also find the acceleration by which 300kg mass will be attracted towqrds 20kg

Discussion

28.	the wavelength of radiation emitted when in He⁺electron falls from infinity to stationary state woul
Answer» the wavelength of radiation emitted when in He⁺electron falls from infinity to stationary state woul

Discussion

29.	A cylindrical piston of mass M slides smoothly inside a long cylinder closed at one end, enclosing a certain mass of gas.The cylinder is kept with its axis horizontal. If the piston is disturbed from its equilibrium position, it oscillates simple harmonically. The period of oscillation will be
Answer» A cylindrical piston of mass $M$ slides smoothly inside a long cylinder closed at one end, enclosing a certain mass of gas. The cylinder is kept with its axis horizontal. If the piston is disturbed from its equilibrium position, it oscillates simple harmonically. The period of oscillation will be

Discussion

30.	{ A force acts on a }2 kg particle whose position is }}{ given by }x=(2t-t^2+3)m . The work done on the }}{ particle in first }4 s is
Answer» { A force acts on a }2 kg particle whose position is }}{ given by }x=(2t-t^2+3)m . The work done on the }}{ particle in first }4 s is

Discussion

31.	Expansion during heating
Answer» Expansion during heating

Discussion

32.	A 3uF capacitor is charged to a potential of 200 v and 2uF at 100v the capacitors are connected in parallel with opposite polarity. Charge flown?
Answer» A 3uF capacitor is charged to a potential of 200 v and 2uF at 100v the capacitors are connected in parallel with opposite polarity. Charge flown?

Discussion

33.	65.A small bob A of mass M is attached at one end of a massless string of length L which is fixed at one end O. The bob is released from the given initial position as shown in the fig. the time period of oscillations will be 1. pi/2 [ sqrt L/g)] 2. pi [sqrt(L/g)] 3. 3( pi/2) {sqrt(L/g)] 4. 2 pi [sqrt(L/g)]
Answer» 65.A small bob A of mass M is attached at one end of a massless string of length L which is fixed at one end O. The bob is released from the given initial position as shown in the fig. the time period of oscillations will be 1. pi/2 [ sqrt L/g)] 2. pi [sqrt(L/g)] 3. 3( pi/2) {sqrt(L/g)] 4. 2 pi [sqrt(L/g)]

Discussion

34.	Two identical particles collide in the air in an perfectly inelastic manner. Before collision, one moves horizontally and the other moves in vertical direction with equal speed. After collision, the fractional loss in kinetic energy of the system of particles is
Answer» Two identical particles collide in the air in an perfectly inelastic manner. Before collision, one moves horizontally and the other moves in vertical direction with equal speed. After collision, the fractional loss in kinetic energy of the system of particles is

Discussion

35.	Two satellites of earth S1 and S2 are moving in the same orbit. The mass of S1 is four times S2. Which one of the following statements is true? (1.) The potential energies of earth and satellite in the two cases are equal (2.) S1 and S2are moving with the same speed (3.) The kinetic energies of the two satellites are equal (4.) The time period of S1 is four times that of S2
Answer» Two satellites of earth S1 and S2 are moving in the same orbit. The mass of S1 is four times S2. Which one of the following statements is true? (1.) The potential energies of earth and satellite in the two cases are equal (2.) S1 and S2are moving with the same speed (3.) The kinetic energies of the two satellites are equal (4.) The time period of S1 is four times that of S2

Discussion

36.	58. O_2 gas weighing 64 g is expanded from 1atm to 0.25atm at 30 degree celsius.calculate entropy change assuming gas to be ideal. a)11.04 cal/mol/k b)22.02 cal/mol/k c)15.24 cal/mol/k d)5.52 cal/mol/k
Answer» 58. O_2 gas weighing 64 g is expanded from 1atm to 0.25atm at 30 degree celsius.calculate entropy change assuming gas to be ideal. a)11.04 cal/mol/k b)22.02 cal/mol/k c)15.24 cal/mol/k d)5.52 cal/mol/k

Discussion

37.	At what value of m1 will 8 kg mass be at rest.
Answer» At what value of $m_{1}$ will 8 kg mass be at rest.

Discussion

38.	A reversible cycle receives 40 kJ of heat from one heat source at a temperature of 127oC and 37 kJ from another heat source at 97oC. The heat rejected (in kJ) to the heat sink at 47oC is64
Answer» A reversible cycle receives $40$ kJ of heat from one heat source at a temperature of $127^{o} C$ and $37$ kJ from another heat source at $97^{o} C$ . The heat rejected (in kJ) to the heat sink at $47^{o} C$ is 64

Discussion

39.	why light with long wavelength bend least while short wavelength bend most
Answer» why light with long wavelength bend least while short wavelength bend most

Discussion

40.	In an experiment to measure the internal resistance of a cell by potentiometer, it is found that the balance point is at a length of 2 m when the cell is shunted by a 5Ω resistance; and is at a length of 3 m when the cell is shunted by a 10Ω resistance. The internal resistance of the cell is, then
Answer» In an experiment to measure the internal resistance of a cell by potentiometer, it is found that the balance point is at a length of 2 m when the cell is shunted by a $5 Ω$ resistance; and is at a length of 3 m when the cell is shunted by a $10 Ω$ resistance. The internal resistance of the cell is, then

Discussion

41.	47.A self inductance coil has a resistance of 31.4ohm and a self inductance of 17mH the frequency of AC at which the impedance is double of the resistance is 1)5000Hz. 2)500Hz 3)50Hz. 4)250Hz
Answer» 47.A self inductance coil has a resistance of 31.4ohm and a self inductance of 17mH the frequency of AC at which the impedance is double of the resistance is 1)5000Hz. 2)500Hz 3)50Hz. 4)250Hz

Discussion

42.	A kid of mass M stands at the edge of a platform of radius R which can be freely rotated about its axis. The moment of inertia of the platform is I. The system is at rest when a friend throws a ball of mass m and the kid catches it. If the velocity of the ball is v horizontally along the tangent to the edge of the platform when it was caught by the kid, find the angular speed of the platform after the event.
Answer» A kid of mass M stands at the edge of a platform of radius R which can be freely rotated about its axis. The moment of inertia of the platform is I. The system is at rest when a friend throws a ball of mass m and the kid catches it. If the velocity of the ball is v horizontally along the tangent to the edge of the platform when it was caught by the kid, find the angular speed of the platform after the event.

Discussion

43.	Water flows through a tube shown in figure. The areas of cross section at A and B are 1 cm2 and 0.5 cm2 respectively. The height difference between A and B is 5 cm. If the speed of water at A is 10 cm s−1, find (a) the speed at B and (b) the difference in pressures at A and B.
Answer» Water flows through a tube shown in figure. The areas of cross section at A and B are 1 $c m^{2}$ and 0.5 $c m^{2}$ respectively. The height difference between A and B is 5 cm. If the speed of water at A is 10 cm $s^{-} 1$ , find (a) the speed at B and (b) the difference in pressures at A and B.

43.

Water flows through a tube shown in figure. The areas of cross section at A and B are 1 cm2 and 0.5 cm2 respectively. The height difference between A and B is 5 cm. If the speed of water at A is 10 cm s−1, find (a) the speed at B and (b) the difference in pressures at A and B.

Answer»

Water flows through a tube shown in figure. The areas of cross section at A and B are 1 $c m^{2}$ and 0.5 $c m^{2}$ respectively. The height difference between A and B is 5 cm. If the speed of water at A is 10 cm $s^{-} 1$ , find (a) the speed at B and (b) the difference in pressures at A and B.

Discussion

44.	A six-foot-tall person is 72 inches tall. How many centimeters tall is a six-foot person?
Answer» A six-foot-tall person is $72$ inches tall. How many centimeters tall is a six-foot person?

Discussion

45.	Arrange these fundamental forces in order of their magnitude, if they act between two protons separated by a distance of 1fm FG is Gravitational force FE is Electromagnetic force FN is Strong Nuclear Force
Answer» Arrange these fundamental forces in order of their magnitude, if they act between two protons separated by a distance of $1 f m$ $F_{G}$ is Gravitational force $F_{E}$ is Electromagnetic force $F_{N}$ is Strong Nuclear Force

Discussion

46.	A photon and an electron have equal energy E. Then the ratio of wavelength of photon to that of electron is proportional to
Answer» A photon and an electron have equal energy E. Then the ratio of wavelength of photon to that of electron is proportional to

Discussion

47.	Two particles P and Q located at a distance of Rp and Rq from the centre of rotation. If Rp is greater than Rq what will be the acceleration on P and Q?? I mean which has more acceleration
Answer» Two particles P and Q located at a distance of Rp and Rq from the centre of rotation. If Rp is greater than Rq what will be the acceleration on P and Q?? I mean which has more acceleration

47.

Two particles P and Q located at a distance of Rp and Rq from the centre of rotation. If Rp is greater than Rq what will be the acceleration on P and Q?? I mean which has more acceleration

Answer»

Two particles P and Q located at a distance of Rp and Rq from the centre of rotation.

If Rp is greater than Rq what will be the acceleration on P and Q??

I mean which has more acceleration

Discussion

48.	A capacitance displacement transducer consists of two triangular plates separated by uniform air gap of 1 mm between fixed and moving plates. The value of capacitance (Cab) between plates of this transducer in pF is (Note: Plates are kept exactly one above the other)Given datax=6 cm,z=6 cm and ε0=8.85×10−12(F/m)15.93
Answer» A capacitance displacement transducer consists of two triangular plates separated by uniform air gap of $1 m m$ between fixed and moving plates. The value of capacitance $(C_{a b})$ between plates of this transducer in $p F$ is (Note: Plates are kept exactly one above the other) Given data $x = 6 c m, z = 6 c m a n d ε_{0} = 8.85 \times 10^{- 12} (F / m)$ 15.93

Discussion

49.	Which of the following plan views of a gusseted base plate will result in minimum base plate thickness?
Answer» Which of the following plan views of a gusseted base plate will result in minimum base plate thickness?

Discussion

50.	a body is projected vertically upward with velocity 30m/s. the dis†an ce coverd by the body between t=2 to t=4. put g=10m/s
Answer» a body is projected vertically upward with velocity 30m/s. the dis†an ce coverd by the body between t=2 to t=4. put g=10m/s

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

Two point charges q1=q2=+2 μC are fixed at x1=+3 m and x2=−3 m as shown in the figure. A third particle of mass 1 g and charge q3=−4 μC is released from rest at y=4 m. Find the speed of the third particle as it reaches the origin.

The speed of a projectile when it is at its maximum height is √25 times its speed at half the maximum height. The angle of projection is

Raindrops of radius 1 mm and mass 4 mg are falling with a speed of 30 m/s on the head and come to rest.Assuming equivalently that the drops cover a dis†an ce equal to their radii on the head,estimate the force exerted by each drop on the head.

A point source of light is arranged at a height h above the surface of water. Where will the image of this source in the flat mirror like bottom of a vessel be if depth of the vessel full of water is d?Refractive index of water is n=4/3. Consider only two steps.

Why ammeter is connected in series and voltmeter in parallel

A converging becam of light forms a sharp image on a screen. A lens is placed in the path of the beam, at 10 cm from the screen, it is found that the screen has to be moved 8 cm further away from the lens to obtam a sharp image. The focal length and the nature of lens is.

Four unchanged capacitors C1,C2,C3 and C4 are connected as shown in the figure. The point A, B, C and D are kept at potential V1,V2,V3 and V4 respectively. Then the potential V0 at point O is

11. If a particle of mass m is moving with constant velocity vparallel to x-axis in x-y plane as shown in fig. Its angularmomentum with respect to origin at any time t will be[MP PET 2011](a) mubk(b)-mub k(c) mubi(d) muiVector A has a magnitidlet

A block of mass m slides down an inclined plane of inclination θ with uniform speed. The coefficient of friction between the block and the plane is μ. The contact force between the block and the plane is

(a) Draw the circuit diagram of an n-p-n transistor amplifer in common emitter configuration. (b) Derive an experssion for voltage gain of the amplifier and hence show that the output voltage is in opposite phase with the input voltage.

A vehicle traveling at a speed of 30 m/ s is accelerated to a velocity of 60 m/ s if the mass of the vehicle is 90 kg and each wheel weights 250 g. Calculate the change in kinetic energy of the vehicle

When a system is taken through the process abc shown in the figure, 90 J of heat is absorbed by the system and 40 J of work is done by it. If the system does 30 J of work during the process adc, how much heat flows into it during the process?

What is the conductivity of a semiconductor sample having electron concentration of 510 raised power 18 m per cube, hole concentation of 510 raised power 19 m per cube, electron mobility of 2.0m per square/V/s and hole mobility of 0.01 m square/ V /s?

1000cells are connected in series and int resistances are in series then what is the drop in the potential in 399 cell

A sound signal is sent through a composite tube as shown in the figure. The radius of the semicircle is R and speed of sound in air is v. If 'n' is an integer, then the frequencies of the signal for obtaining maximum value of intensity are given by

15.A bar magnet of magnetic moment M is bent in the U shape such that all parts are of equal lengths. Then the new magnetic moment is

ntA particle ismoving in x-y plane in a circular path with centre at origin . If at an instant the position of particle is given by [1/root of 2 ](i+j), the velocity of particle is along ?n

For an oscillating pendulum does the tension of string remains same or changes?

(a) Write three characteristic properties of nuclear force. (b) Draw a plot of potential energy of a pair of nucleons as a function of their separation. Write two important conclusions that can be drawn from the graph.

If we can throw a ball upto a maximum height H, the maximum horizontal distance to which we can throw it is

Find derivative of f(x)=elnx+sinx+8

there are two object of mass 20kg and 300kg. let m_1=20kg and m_2=300kg. what is the acceleration by which object of mass 20kg will be attracted to the mass of 300kg. also find the acceleration by which 300kg mass will be attracted towqrds 20kg

the wavelength of radiation emitted when in He⁺electron falls from infinity to stationary state woul

A cylindrical piston of mass M slides smoothly inside a long cylinder closed at one end, enclosing a certain mass of gas.The cylinder is kept with its axis horizontal. If the piston is disturbed from its equilibrium position, it oscillates simple harmonically. The period of oscillation will be

{ A force acts on a }2 kg particle whose position is }}{ given by }x=(2t-t^2+3)m . The work done on the }}{ particle in first }4 s is

Expansion during heating

A 3uF capacitor is charged to a potential of 200 v and 2uF at 100v the capacitors are connected in parallel with opposite polarity. Charge flown?

Two identical particles collide in the air in an perfectly inelastic manner. Before collision, one moves horizontally and the other moves in vertical direction with equal speed. After collision, the fractional loss in kinetic energy of the system of particles is

58. O_2 gas weighing 64 g is expanded from 1atm to 0.25atm at 30 degree celsius.calculate entropy change assuming gas to be ideal. a)11.04 cal/mol/k b)22.02 cal/mol/k c)15.24 cal/mol/k d)5.52 cal/mol/k

At what value of m1 will 8 kg mass be at rest.

A reversible cycle receives 40 kJ of heat from one heat source at a temperature of 127oC and 37 kJ from another heat source at 97oC. The heat rejected (in kJ) to the heat sink at 47oC is64

why light with long wavelength bend least while short wavelength bend most

47.A self inductance coil has a resistance of 31.4ohm and a self inductance of 17mH the frequency of AC at which the impedance is double of the resistance is 1)5000Hz. 2)500Hz 3)50Hz. 4)250Hz

Water flows through a tube shown in figure. The areas of cross section at A and B are 1 cm2 and 0.5 cm2 respectively. The height difference between A and B is 5 cm. If the speed of water at A is 10 cm s−1, find (a) the speed at B and (b) the difference in pressures at A and B.

A six-foot-tall person is 72 inches tall. How many centimeters tall is a six-foot person?

Arrange these fundamental forces in order of their magnitude, if they act between two protons separated by a distance of 1fm FG is Gravitational force FE is Electromagnetic force FN is Strong Nuclear Force

A photon and an electron have equal energy E. Then the ratio of wavelength of photon to that of electron is proportional to

Two particles P and Q located at a distance of Rp and Rq from the centre of rotation. If Rp is greater than Rq what will be the acceleration on P and Q?? I mean which has more acceleration

Which of the following plan views of a gusseted base plate will result in minimum base plate thickness?

a body is projected vertically upward with velocity 30m/s. the dis†an ce coverd by the body between t=2 to t=4. put g=10m/s