50278 + Interview Questions in Physics

1.	A gun of weight of 10 kg fires a shot of 0.5gwith a velocity 230 m/s. Velocity of recoil gunis-(1) 1.51 cm/sec() 1.5 cm/sec(3)1.15 cm/sec(4) 1.10 cm/sec
Answer» A gun of weight of 10 kg fires a shot of 0.5gwith a velocity 230 m/s. Velocity of recoil gunis-(1) 1.51 cm/sec() 1.5 cm/sec(3)1.15 cm/sec(4) 1.10 cm/sec

Discussion

2.	Figure shows the variation of force acting on a body with time. Assuming the body to start from rest, the variation of its momentum with time is best represented by which plot?
Answer» Figure shows the variation of force acting on a body with time. Assuming the body to start from rest, the variation of its momentum with time is best represented by which plot?

Discussion

3.	ABCD is a square where each side is a uniform wire of resistance 1 Ω. A point E lies on CD such that if a uniform wire of resistance 1 Ω is connected across AE and constant potential difference is applied across A and C, then B and E are equipotential, if
Answer» $A B C D$ is a square where each side is a uniform wire of resistance $1 Ω$ . A point $E$ lies on $C D$ such that if a uniform wire of resistance $1 Ω$ is connected across $A E$ and constant potential difference is applied across $A$ and $C$ , then $B$ and $E$ are equipotential, if

Discussion

4.	A ball is dropped from the top of a tower 120 m high and simultaneously another ball is projected vertically upwards from the ground with a speed of 30 m/s. The two balls will meet after
Answer» A ball is dropped from the top of a tower $120 m$ high and simultaneously another ball is projected vertically upwards from the ground with a speed of $30 m/s$ . The two balls will meet after

Discussion

5.	A block of mass m moving at a speed v compresses a spring through a distance x before its speed is speed is halved. Find the spring constant of the spring.
Answer» A block of mass m moving at a speed v compresses a spring through a distance x before its speed is speed is halved. Find the spring constant of the spring.

Discussion

6.	The figure shows a uniform spherical shell of mass M. The point A is not at the centre but away from the centre of the shell. If a particle of mass m is placed at A, then
Answer» The figure shows a uniform spherical shell of mass M. The point A is not at the centre but away from the centre of the shell. If a particle of mass m is placed at A, then

6.

The figure shows a uniform spherical shell of mass M. The point A is not at the centre but away from the centre of the shell. If a particle of mass m is placed at A, then

Answer»

The figure shows a uniform spherical shell of mass M. The point A is not at the centre but away from the centre of the shell. If a particle of mass m is placed at A, then

Discussion

7.	43. The ratio of resolving powers of an optical microscope for two wavelengths 4000 A , and 6000 A is
Answer» 43. The ratio of resolving powers of an optical microscope for two wavelengths 4000 A , and 6000 A is

Discussion

8.	A mirror which can focus the parallel rays after reflection from its surface is:
Answer» A mirror which can focus the parallel rays after reflection from its surface is:

8.

A mirror which can focus the parallel rays after reflection from its surface is:

Answer»

A mirror which can focus the parallel rays after reflection from its surface is:

Discussion

9.	What is torque in law of conservation of angular momentum in easy words
Answer» What is torque in law of conservation of angular momentum in easy words

Discussion

10.	How many neutrons andprotons are there in the following nuclei?,,,,
Answer» How many neutrons and protons are there in the following nuclei? , , , ,

10.

How many neutrons andprotons are there in the following nuclei?,,,,

Answer»

How many neutrons and
protons are there in the following nuclei?

,
,
,
,

Discussion

11.	Rolle's theorem is verified for the function y = x2 + 2,in the interval[a,b] and a = -2. Find the smallest integral value of b
Answer» Rolle's theorem is verified for the function y = x² + 2,in the interval[a,b] and a = -2. Find the smallest integral value of b

Discussion

12.	A string of length 0.4 m and mass 10−2 kg is tightly clamped at its ends. The tension in the string is 1.6 N. Identical wave pulses are produced at one end at equal intervals of time Δt. The minimum value of Δt which allows constructive interference between successive pulses is
Answer» A string of length 0.4 m and mass $10^{- 2}$ kg is tightly clamped at its ends. The tension in the string is 1.6 N. Identical wave pulses are produced at one end at equal intervals of time $Δ t$ . The minimum value of $Δ t$ which allows constructive interference between successive pulses is

12.

A string of length 0.4 m and mass 10−2 kg is tightly clamped at its ends. The tension in the string is 1.6 N. Identical wave pulses are produced at one end at equal intervals of time Δt. The minimum value of Δt which allows constructive interference between successive pulses is

Answer»

A string of length 0.4 m and mass $10^{- 2}$ kg is tightly clamped at its ends. The tension in the string is 1.6 N. Identical wave pulses are produced at one end at equal intervals of time $Δ t$ . The minimum value of $Δ t$ which allows constructive interference between successive pulses is

Discussion

13.	In a common - emitter amplifier, output resistance is 5000 Ω and input resitance is 2000 Ω. If peak value of signal voltage is 10 mV and β=50, then the peak value of output voltage is
Answer» In a common - emitter amplifier, output resistance is $5000 Ω$ and input resitance is $2000 Ω$ . If peak value of signal voltage is $10 m V$ and $β = 50,$ then the peak value of output voltage is

Discussion

14.	A circular platform is mounted on a frictionless vertical axle. Its radius R = 2 m and its moment of inertia about the axle is 200 kg m2. It is initially at rest. A 50 kg man stands on the edge of the platform and begins to walk along the edge at the speed of 1 ms−1 relative to the ground. Time taken by the man to complete one revolution is
Answer» A circular platform is mounted on a frictionless vertical axle. Its radius R = 2 m and its moment of inertia about the axle is 200 kg $m^{2} .$ It is initially at rest. A 50 kg man stands on the edge of the platform and begins to walk along the edge at the speed of 1 $m s^{- 1}$ relative to the ground. Time taken by the man to complete one revolution is

Discussion

15.	A block of mass 100 gm slides on a rough horizontal surface. If the speed of the block decreases from 10 m/s to 5 m/s, the thermal energy developed in the process is
Answer» A block of mass 100 gm slides on a rough horizontal surface. If the speed of the block decreases from 10 m/s to 5 m/s, the thermal energy developed in the process is

Discussion

16.	The output 'Y' of the multiplexer circuit shown in figure below is
Answer» The output 'Y' of the multiplexer circuit shown in figure below is

Discussion

17.	A small sized mass m is attached by a massless string (of length L) to the top of a fixed frictionless solid cone whose axis is vertical. The half angle at the vertex of the cone is θ. If the mass m moves around in a horizontal circle at speed v, what is the maximum value of v for which the mass stays in contact with the cone? (g is acceleration due to gravity)
Answer» A small sized mass $m$ is attached by a massless string (of length $L$ ) to the top of a fixed frictionless solid cone whose axis is vertical. The half angle at the vertex of the cone is $θ$ . If the mass $m$ moves around in a horizontal circle at speed $v$ , what is the maximum value of $v$ for which the mass stays in contact with the cone? ( $g$ is acceleration due to gravity)

Discussion

18.	A rod is of length 2 m and mass 1kg. What will be its moment of inertia about an axis perpendicular to its length and passing through one of its end?
Answer» A rod is of length 2 m and mass 1kg. What will be its moment of inertia about an axis perpendicular to its length and passing through one of its end?

Discussion

19.	Find the magnitude of net magnetic field at point P as shown in figure. If two loops of wire carry the same current of 10 mA, but the flow of current is in opposite directions. One loop has a radius of R1=50 cm and the other loop has a radius of R2=100 cm. The distance of point P from first loop is 0.25 m and from second loop is 0.75 m.[Take, (0.252+0.52)3/2=0.175; (1+0.752)3/2=1.95]
Answer» Find the magnitude of net magnetic field at point $P$ as shown in figure. If two loops of wire carry the same current of $10 mA$ , but the flow of current is in opposite directions. One loop has a radius of $R_{1} = 50 cm$ and the other loop has a radius of $R_{2} = 100 cm$ . The distance of point $P$ from first loop is $0.25 m$ and from second loop is $0.75 m$ . [Take, $({0.25}^{2} + {0.5}^{2})^{3 / 2} = 0.175; (1 + {0.75}^{2})^{3 / 2} = 1.95$ ]

Discussion

20.	The resistance of a bulb filament is 100 Ω at a temperature of 100∘C. If its temperature coefficient of resistance be 0.005 / ∘C, its resistance will become 200 Ω at a temperature of
Answer» The resistance of a bulb filament is $100 Ω$ at a temperature of $100^{\circ} C$ . If its temperature coefficient of resistance be $0.005$ / $^{\circ} C$ , its resistance will become $200 Ω$ at a temperature of

Discussion

21.	It is observed that some of the spectral lines in hydrogen spectrum have wavelengths almost equal to those of the spectral lines in He+ ion, Out of the following the transitions in He+ that will make this possible is
Answer» It is observed that some of the spectral lines in hydrogen spectrum have wavelengths almost equal to those of the spectral lines in $H e^{+}$ ion, Out of the following the transitions in $H e^{+}$ that will make this possible is

Discussion

22.	what is plasma and bose instine condenset?
Answer» what is plasma and bose instine condenset?

Discussion

23.	A point charge Q = 20 nC is located at the origin in the cartesian plane. The charge is surrounded with a medium having relative permittivity of 2.5. The magnitude of electric flux density at point P(1, 2, -2)m is _____pC/m2.(Answer upto 2 decimal places)176.83
Answer» A point charge Q = 20 nC is located at the origin in the cartesian plane. The charge is surrounded with a medium having relative permittivity of 2.5. The magnitude of electric flux density at point P(1, 2, -2)m is _____pC/ $m^{2}$ .(Answer upto 2 decimal places) 176.83

Discussion

24.	If x is the distance of an object from the focus of a concave mirror and y is the distance of image from the focus, then which of the following graphs is correct between x and y
Answer» If x is the distance of an object from the focus of a concave mirror and y is the distance of image from the focus, then which of the following graphs is correct between x and y

Discussion

25.	Two successive resonance frequencies in an open organ pipe are 1620 Hz and 2268 Hz. Find the length of the tube. The speed of sound in air is 324ms−1.
Answer» Two successive resonance frequencies in an open organ pipe are 1620 Hz and 2268 Hz. Find the length of the tube. The speed of sound in air is $324 m s^{- 1}$ .

Discussion

26.	Two capacitors are placed in parallel. Why do the positive plates of each capacitor have same potential? Also, why do the negative plates of each capacitor have same potential?
Answer» Two capacitors are placed in parallel. Why do the positive plates of each capacitor have same potential? Also, why do the negative plates of each capacitor have same potential?

Discussion

27.	Which of the following statement is true?
Answer» Which of the following statement is true?

Discussion

28.	An electron is released from the origin at a place where a uniform electric field E and a uniform magnetic field B exist along the negative y axis and negative z axis respectively. Find the displacement of the electron along y axis when it's velocity becomes perpendicular to the electric field for the first time
Answer» An electron is released from the origin at a place where a uniform electric field E and a uniform magnetic field B exist along the negative y axis and negative z axis respectively. Find the displacement of the electron along y axis when it's velocity becomes perpendicular to the electric field for the first time

Discussion

29.	Estimate the distance for which ray optics is good approximationfor an aperture of 4 mm and wavelength 400 nm.
Answer» Estimate the distance for which ray optics is good approximationfor an aperture of 4 mm and wavelength 400 nm.

Discussion

30.	The wave length of Kα, x- rays produced by an x-ray tube is λ. The atomic number of the anode material of the tube is: (Constants have their usual meanings)
Answer» The wave length of $K_{α}$ , x- rays produced by an x-ray tube is $λ$ . The atomic number of the anode material of the tube is: (Constants have their usual meanings)

Discussion

31.	a small square shaped loop of edge length l is placed at the centre of a circular loop a of radius r with its plane perpendicular to plane of the circular loop the coefficient of mutual induc†an ce is
Answer» a small square shaped loop of edge length l is placed at the centre of a circular loop a of radius r with its plane perpendicular to plane of the circular loop the coefficient of mutual induc†an ce is

Discussion

32.	A particle starts from rest and travels a distance d with uniform acceleration, then it travels a distance 2d with uniform speed and finally it travels a distance 3d with uniform retardatron to come to rest. Ratio of average velocity to maximum velocity is
Answer» A particle starts from rest and travels a distance d with uniform acceleration, then it travels a distance 2d with uniform speed and finally it travels a distance 3d with uniform retardatron to come to rest. Ratio of average velocity to maximum velocity is

Discussion

33.	What is schrodinger wave equation? What is psi in the equation? Where do we use it?
Answer» What is schrodinger wave equation? What is psi in the equation? Where do we use it?

Discussion

34.	v)Write a short note o Ellingham diagram and its application.
Answer» v)Write a short note o Ellingham diagram and its application.

Discussion

35.	Nuclei of a radioactive element is produced at constant rate α and they decay with decay constant λ. At t=0, the number of nuclei is 0. The number of active nuclei at time t is
Answer» Nuclei of a radioactive element is produced at constant rate $α$ and they decay with decay constant $λ$ . At $t = 0$ , the number of nuclei is 0. The number of active nuclei at time $t$ is

Discussion

36.	A block of mass m is placed on a suface with a vertical cross section given by y=x36. If the coefficient of friction is 0.5, the maximum height above the ground at which the block can be placed without slipping is:
Answer» A block of mass m is placed on a suface with a vertical cross section given by $y = \frac{x^{3}}{6} .$ If the coefficient of friction is $0.5$ , the maximum height above the ground at which the block can be placed without slipping is:

Discussion

37.	In a circuit, three resistance P, Q and R are connected in the three arms and the fourth arm is formed by two resistance S1 and S2 connected in parallel. The condition for which the circuit will become a balanced wheatstone bridge is
Answer» In a circuit, three resistance $P, Q$ and $R$ are connected in the three arms and the fourth arm is formed by two resistance $S_{1}$ and $S_{2}$ connected in parallel. The condition for which the circuit will become a balanced wheatstone bridge is

Discussion

38.	Find equivalent resistance of the circuit between the terminal A and B.
Answer» Find equivalent resistance of the circuit between the terminal $A$ and $B$ .

Discussion

39.	1 g mole of an ideal gas at STP is subjected to a reversible adiabatic expansion to double its volume. Find the change in internal energy (γ=1.4).
Answer» $1 g$ mole of an ideal gas at STP is subjected to a reversible adiabatic expansion to double its volume. Find the change in internal energy $(γ = 1.4)$ .

Discussion

40.	In the shown figure, the strings are massless. If the vertical rod is rotated the tension in upper string is 35 N then the speed of the ball is
Answer» In the shown figure, the strings are massless. If the vertical rod is rotated the tension in upper string is $35 N$ then the speed of the ball is

Discussion

41.	A charge 'q' is uniformly distributed on a ring of radius 'r'. A sphere of an equal radius is constructed with its centre lying on the periphery of the ring. The flux of electric field through the surface of the sphere will be?
Answer» A charge 'q' is uniformly distributed on a ring of radius 'r'. A sphere of an equal radius is constructed with its centre lying on the periphery of the ring. The flux of electric field through the surface of the sphere will be?

Discussion

42.	3.The figure shows a silvered lens .Ua=1.6 and Ub= 1.2, R1=80cm ,R2=40cm and R3=20cm. An object is placed at a distance of 12cm from this lens.find the image distance.
Answer» 3.The figure shows a silvered lens .Ua=1.6 and Ub= 1.2, R1=80cm ,R2=40cm and R3=20cm. An object is placed at a distance of 12cm from this lens.find the image distance.

Discussion

43.	The gravitational potential due to earth at infinite dis†an ce from it is zero.Let the gravitational potential at point p be -5J/kg.Suppose we arbitarily asdume gravitational potential at infinity +10j/kg then gravitational potential at point
Answer» The gravitational potential due to earth at infinite dis†an ce from it is zero.Let the gravitational potential at point p be -5J/kg.Suppose we arbitarily asdume gravitational potential at infinity +10j/kg then gravitational potential at point

Discussion

44.	compare the time periods of a simple pendulum at places where g=9.8m/s and 4.36m/s respectively
Answer» compare the time periods of a simple pendulum at places where g=9.8m/s and 4.36m/s respectively

Discussion

45.	A part of the circuit is shown in the figure.All the capacitors have capacitance of 2μF.
Answer» A part of the circuit is shown in the figure. All the capacitors have capacitance of 2μF.

Discussion

46.	At what angle with the horizontal should a ball be thrown so that the range R is related to the time of flight (T) as R=5T2?(Take g=10 m/s2)
Answer» At what angle with the horizontal should a ball be thrown so that the range $R$ is related to the time of flight $(T)$ as $R = 5 T^{2} ? (Take g = 10 {m/s}^{2})$

Discussion

47.	A body moving with uniform retardation covers 3 km before its speed is reduced to half of its initial value come to rest in another distance of___
Answer» A body moving with uniform retardation covers 3 km before its speed is reduced to half of its initial value come to rest in another distance of___

Discussion

48.	Three concentric spherical conductors are arranged as shown in the figure. The potential at point P will be:
Answer» Three concentric spherical conductors are arranged as shown in the figure. The potential at point $P$ will be:

Discussion

49.	equation of trajectory of particle is y=3x -4x^{2. } acceleration is constnt 2 and directed along negative y axis. velocity when it passes through origi
Answer» equation of trajectory of particle is y=3x -4x^{2. } acceleration is constnt 2 and directed along negative y axis. velocity when it passes through origi

Discussion

50.	A carrier signal is frequency modulated by a sinusoidal message signal of 15 kHz, resulting in a maximum frequency deviation of 50 kHz. If the amplitude of the message signal is increased by a factor of 3 and it's frequency is decreased to 5 kHz, then the bandwidth of the modified FM signal (according to Carson's rule) will be equal to ______ kHz.310
Answer» A carrier signal is frequency modulated by a sinusoidal message signal of 15 kHz, resulting in a maximum frequency deviation of 50 kHz. If the amplitude of the message signal is increased by a factor of 3 and it's frequency is decreased to 5 kHz, then the bandwidth of the modified FM signal (according to Carson's rule) will be equal to ______ kHz. 310

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

A gun of weight of 10 kg fires a shot of 0.5gwith a velocity 230 m/s. Velocity of recoil gunis-(1) 1.51 cm/sec() 1.5 cm/sec(3)1.15 cm/sec(4) 1.10 cm/sec

Figure shows the variation of force acting on a body with time. Assuming the body to start from rest, the variation of its momentum with time is best represented by which plot?

ABCD is a square where each side is a uniform wire of resistance 1 Ω. A point E lies on CD such that if a uniform wire of resistance 1 Ω is connected across AE and constant potential difference is applied across A and C, then B and E are equipotential, if

A ball is dropped from the top of a tower 120 m high and simultaneously another ball is projected vertically upwards from the ground with a speed of 30 m/s. The two balls will meet after

A block of mass m moving at a speed v compresses a spring through a distance x before its speed is speed is halved. Find the spring constant of the spring.

The figure shows a uniform spherical shell of mass M. The point A is not at the centre but away from the centre of the shell. If a particle of mass m is placed at A, then

43. The ratio of resolving powers of an optical microscope for two wavelengths 4000 A , and 6000 A is

A mirror which can focus the parallel rays after reflection from its surface is:

What is torque in law of conservation of angular momentum in easy words

How many neutrons andprotons are there in the following nuclei?,,,,

Rolle's theorem is verified for the function y = x2 + 2,in the interval[a,b] and a = -2. Find the smallest integral value of b

A string of length 0.4 m and mass 10−2 kg is tightly clamped at its ends. The tension in the string is 1.6 N. Identical wave pulses are produced at one end at equal intervals of time Δt. The minimum value of Δt which allows constructive interference between successive pulses is

In a common - emitter amplifier, output resistance is 5000 Ω and input resitance is 2000 Ω. If peak value of signal voltage is 10 mV and β=50, then the peak value of output voltage is

A block of mass 100 gm slides on a rough horizontal surface. If the speed of the block decreases from 10 m/s to 5 m/s, the thermal energy developed in the process is

The output 'Y' of the multiplexer circuit shown in figure below is

A rod is of length 2 m and mass 1kg. What will be its moment of inertia about an axis perpendicular to its length and passing through one of its end?

The resistance of a bulb filament is 100 Ω at a temperature of 100∘C. If its temperature coefficient of resistance be 0.005 / ∘C, its resistance will become 200 Ω at a temperature of

It is observed that some of the spectral lines in hydrogen spectrum have wavelengths almost equal to those of the spectral lines in He+ ion, Out of the following the transitions in He+ that will make this possible is

what is plasma and bose instine condenset?

A point charge Q = 20 nC is located at the origin in the cartesian plane. The charge is surrounded with a medium having relative permittivity of 2.5. The magnitude of electric flux density at point P(1, 2, -2)m is _____pC/m2.(Answer upto 2 decimal places)176.83

If x is the distance of an object from the focus of a concave mirror and y is the distance of image from the focus, then which of the following graphs is correct between x and y

Two successive resonance frequencies in an open organ pipe are 1620 Hz and 2268 Hz. Find the length of the tube. The speed of sound in air is 324ms−1.

Two capacitors are placed in parallel. Why do the positive plates of each capacitor have same potential? Also, why do the negative plates of each capacitor have same potential?

Which of the following statement is true?

Estimate the distance for which ray optics is good approximationfor an aperture of 4 mm and wavelength 400 nm.

The wave length of Kα, x- rays produced by an x-ray tube is λ. The atomic number of the anode material of the tube is: (Constants have their usual meanings)

a small square shaped loop of edge length l is placed at the centre of a circular loop a of radius r with its plane perpendicular to plane of the circular loop the coefficient of mutual induc†an ce is

A particle starts from rest and travels a distance d with uniform acceleration, then it travels a distance 2d with uniform speed and finally it travels a distance 3d with uniform retardatron to come to rest. Ratio of average velocity to maximum velocity is

What is schrodinger wave equation? What is psi in the equation? Where do we use it?

v)Write a short note o Ellingham diagram and its application.

Nuclei of a radioactive element is produced at constant rate α and they decay with decay constant λ. At t=0, the number of nuclei is 0. The number of active nuclei at time t is

A block of mass m is placed on a suface with a vertical cross section given by y=x36. If the coefficient of friction is 0.5, the maximum height above the ground at which the block can be placed without slipping is:

In a circuit, three resistance P, Q and R are connected in the three arms and the fourth arm is formed by two resistance S1 and S2 connected in parallel. The condition for which the circuit will become a balanced wheatstone bridge is

Find equivalent resistance of the circuit between the terminal A and B.

1 g mole of an ideal gas at STP is subjected to a reversible adiabatic expansion to double its volume. Find the change in internal energy (γ=1.4).

In the shown figure, the strings are massless. If the vertical rod is rotated the tension in upper string is 35 N then the speed of the ball is

A charge 'q' is uniformly distributed on a ring of radius 'r'. A sphere of an equal radius is constructed with its centre lying on the periphery of the ring. The flux of electric field through the surface of the sphere will be?

3.The figure shows a silvered lens .Ua=1.6 and Ub= 1.2, R1=80cm ,R2=40cm and R3=20cm. An object is placed at a distance of 12cm from this lens.find the image distance.

The gravitational potential due to earth at infinite dis†an ce from it is zero.Let the gravitational potential at point p be -5J/kg.Suppose we arbitarily asdume gravitational potential at infinity +10j/kg then gravitational potential at point

compare the time periods of a simple pendulum at places where g=9.8m/s and 4.36m/s respectively

A part of the circuit is shown in the figure.All the capacitors have capacitance of 2μF.

At what angle with the horizontal should a ball be thrown so that the range R is related to the time of flight (T) as R=5T2?(Take g=10 m/s2)

A body moving with uniform retardation covers 3 km before its speed is reduced to half of its initial value come to rest in another distance of___

Three concentric spherical conductors are arranged as shown in the figure. The potential at point P will be:

equation of trajectory of particle is y=3x -4x^{2. } acceleration is constnt 2 and directed along negative y axis. velocity when it passes through origi