16569 + Interview Questions in Physics

1.	22.A conducting loop in the shape of a right angled isosceles triangle of height 10 cm is kept such that the 90^° vertex is very close an infinitely long conducting wire (see in the figure). The wire is electrically insulated from the loop. The hypotenuse of the loop is parallel to the wire. The current in the triangular loop is in counterclockwise direction and is increased at a constant rate of 10 A per second. Which of the following statement(s) is / are correct:
Answer» 22.A conducting loop in the shape of a right angled isosceles triangle of height 10 cm is kept such that the 90^° vertex is very close an infinitely long conducting wire (see in the figure). The wire is electrically insulated from the loop. The hypotenuse of the loop is parallel to the wire. The current in the triangular loop is in counterclockwise direction and is increased at a constant rate of 10 A per second. Which of the following statement(s) is / are correct:

Discussion

2.	magnetic induction at centre point of axis of long solenoid is B. if length of solenoid is reduced to half and same wire is wound over it in 2 layers then new magnetic induction i
Answer» magnetic induction at centre point of axis of long solenoid is B. if length of solenoid is reduced to half and same wire is wound over it in 2 layers then new magnetic induction i

Discussion

3.	A cone of base radius R and height h is placed in an uniform electric field E which is parallel to base of cone . The electric flux entering the cone will b
Answer» A cone of base radius R and height h is placed in an uniform electric field E which is parallel to base of cone . The electric flux entering the cone will b

Discussion

4.	Two thin metalic sprerical shells of radii r1 and r2(r1<r2) are placed with their centres coinciding. A material of thermal conductivity K is filled in the spave between the shells. The inner shell is maintained at temperature θ1 and the outer shell at temperature θ2(θ1<θ2). The rate at which heat flows radially through the material is
Answer» Two thin metalic sprerical shells of radii $r_{1}$ and $r_{2} (r_{1} < r_{2})$ are placed with their centres coinciding. A material of thermal conductivity $K$ is filled in the spave between the shells. The inner shell is maintained at temperature $θ_{1}$ and the outer shell at temperature $θ_{2} (θ_{1} < θ_{2})$ . The rate at which heat flows radially through the material is

Discussion

5.	Two equal positive charge Q are fixed at points (-a,0) and ( a,0 ) on the x axis .an opposite charge -q at the rest is released from point (0, a) on the y axis .the charge on -q will be
Answer» Two equal positive charge Q are fixed at points (-a,0) and ( a,0 ) on the x axis .an opposite charge -q at the rest is released from point (0, a) on the y axis .the charge on -q will be

Discussion

6.	A small electric dipole is placed in x-y plane at origin with its dipole moment directed along positive x-axis. The direction of electric field at point (2,2/2, 0) is
Answer» A small electric dipole is placed in x-y plane at origin with its dipole moment directed along positive x-axis. The direction of electric field at point (2,2/2, 0) is

Discussion

7.	Two identical small bodies each of mass m and charge q are suspended from 2 strings each of length l from a common fixed point in an orbiting artificial satellite, then the tension in strings will be
Answer» Two identical small bodies each of mass m and charge q are suspended from 2 strings each of length l from a common fixed point in an orbiting artificial satellite, then the tension in strings will be

Discussion

8.	The refractive index of water is 43. The speed of light in water is: (Take the speed of light in air =3×108 ms−1)
Answer» The refractive index of water is $\frac{4}{3}$ . The speed of light in water is: (Take the speed of light in air $= 3 \times 10^{8} m s^{- 1}$ )

8.

The refractive index of water is 43. The speed of light in water is: (Take the speed of light in air =3×108 ms−1)

Answer»

The refractive index of water is $\frac{4}{3}$ . The speed of light in water is:

(Take the speed of light in air $= 3 \times 10^{8} m s^{- 1}$ )

Discussion

9.	Why electric current is a scalar quantity until and unless it has magnitude and direction both?
Answer» Why electric current is a scalar quantity until and unless it has magnitude and direction both?

Discussion

10.	Show that if a ray of light is reflected successively from two mirrors inclined at an angle q, the deviation of the ray does not depend upon the angle of incidence.
Answer» Show that if a ray of light is reflected successively from two mirrors inclined at an angle q, the deviation of the ray does not depend upon the angle of incidence.

Discussion

11.	A diver in a swimming pool wants to signal his distress to a person lying on the edge of the pool by flashing his water proof flash light
Answer» A diver in a swimming pool wants to signal his distress to a person lying on the edge of the pool by flashing his water proof flash light

Discussion

12.	What are audible and inaudible sounds? What is the audibility frequency range for human ear?
Answer» What are audible and inaudible sounds? What is the audibility frequency range for human ear?

Discussion

13.	Question 1 Define 1 dioptre of power of a lens.
Answer» Question 1 Define 1 dioptre of power of a lens.

Discussion

14.	A student obtained a sharp image of a burning candle, placed at the farther end of a laboratory table, on a screen using a concave mirror. For getting better value of focal length of the mirror, the subject teacher suggested him for focusing a well illuminated distant object. What should the student do?
Answer» A student obtained a sharp image of a burning candle, placed at the farther end of a laboratory table, on a screen using a concave mirror. For getting better value of focal length of the mirror, the subject teacher suggested him for focusing a well illuminated distant object. What should the student do?

Discussion

15.	Real, inverted and enlarged image will be formed in case of:
Answer» Real, inverted and enlarged image will be formed in case of:

Discussion

16.	In the given circuit, the current through the 5 mH inductor, in steady state, will be -
Answer» In the given circuit, the current through the $5 mH$ inductor, in steady state, will be -

Discussion

17.	The velocity of electron in the hydrogen atom is 2×10^6 m/s. The radius of orbit is 5×10^-11 m. The magnetic induction at the centre of orbit in tesla will be
Answer» The velocity of electron in the hydrogen atom is 2×10^6 m/s. The radius of orbit is 5×10^-11 m. The magnetic induction at the centre of orbit in tesla will be

Discussion

18.	With the help of a labeled diagram, explain why the sun appears reddish at the sun-rise and the sun-set.
Answer» With the help of a labeled diagram, explain why the sun appears reddish at the sun-rise and the sun-set.

Discussion

19.	How does the force of gravitation between two objects change when the distance between them is reduced to half?
Answer» How does the force of gravitation between two objects change when the distance between them is reduced to half?

Discussion

20.	Which of these steps when we incorporate in our life will helps us in consumption of resources in a sustainable manner.
Answer» Which of these steps when we incorporate in our life will helps us in consumption of resources in a sustainable manner.

Discussion

21.	A uniform magnetic field of 1.5 T exists in a cylindrical region ofradius10.0 cm, its direction parallel to the axis along east to west. Awire carrying current of 7.0 A in the north to south direction passesthrough this region. What is the magnitude and direction of theforce on the wire if, (a) the wire intersects the axis, (b) the wire is turned from N-S to northeast-northwest direction, (c) the wire in the N-S direction is lowered from the axis by a distanceof 6.0 cm?
Answer» A uniform magnetic field of 1.5 T exists in a cylindrical region ofradius10.0 cm, its direction parallel to the axis along east to west. Awire carrying current of 7.0 A in the north to south direction passesthrough this region. What is the magnitude and direction of theforce on the wire if, (a) the wire intersects the axis, (b) the wire is turned from N-S to northeast-northwest direction, (c) the wire in the N-S direction is lowered from the axis by a distanceof 6.0 cm?

Discussion

22.	Calculate the energy associated with the first orbit of he^+. What is the radius of this orbit?
Answer» Calculate the energy associated with the first orbit of he^+. What is the radius of this orbit?

Discussion

23.	Which kind of pattern do the musical notes follow?
Answer» Which kind of pattern do the musical notes follow?

Discussion

24.	An engine develops 10 kW of power. How much time will it take to lift a mass of 200 kg to a height of 40 m. (g=10m/sec2)
Answer» An engine develops 10 kW of power. How much time will it take to lift a mass of 200 kg to a height of 40 m. ( $g = 10 m / s e c^{2}$ )

24.

An engine develops 10 kW of power. How much time will it take to lift a mass of 200 kg to a height of 40 m. (g=10m/sec2)

Answer»

An engine develops 10 kW of power. How much time will it take to lift a mass of 200 kg to a height of 40 m. ( $g = 10 m / s e c^{2}$ )

Discussion

25.	If a point charge is placed at the corner of cube then why we have taken fi total as q/8E
Answer» If a point charge is placed at the corner of cube then why we have taken fi total as q/8E

Discussion

26.	19. Expression for gravitational potential
Answer» 19. Expression for gravitational potential

Discussion

27.	(a) At what position a candle of length 3 cm be placed in front of a convex lens so that its image of length 6 cm be obtained on a screen placed at distance 30 cm behind the lens ? (b) What is the focal length of lens in part (a) ?
Answer» (a) At what position a candle of length 3 cm be placed in front of a convex lens so that its image of length 6 cm be obtained on a screen placed at distance 30 cm behind the lens ? (b) What is the focal length of lens in part (a) ?

27.

(a) At what position a candle of length 3 cm be placed in front of a convex lens so that its image of length 6 cm be obtained on a screen placed at distance 30 cm behind the lens ? (b) What is the focal length of lens in part (a) ?

Answer»

(a) At what position a candle of length 3 cm be placed in front of a convex lens so that its image of length 6 cm be obtained on a screen placed at distance 30 cm behind the lens ?

(b) What is the focal length of lens in part (a) ?

Discussion

28.	A capacitor is half filled with a dielectric (K = 2) as shown in figure A. If the same capacitor is to be filled with same dielectric as shown, what would be the thickness of dielectric so that capacitor still has same capacity ?
Answer» A capacitor is half filled with a dielectric (K = 2) as shown in figure A. If the same capacitor is to be filled with same dielectric as shown, what would be the thickness of dielectric so that capacitor still has same capacity ?

Discussion

29.	Calculate the kinetic energy of a body of mass 2 kg moving with a speed of 10ms−1.
Answer» Calculate the kinetic energy of a body of mass 2 kg moving with a speed of $10 m s^{- 1} .$

Discussion

30.	A piece of copper of mass 50g is drawn into a wire of length 50m.Find the resistance of the Wire . The density and Specific resistance Of Copper are 8.9 x 10^3 kg/m^3 and 1.7x10^-8 ohm-m restpectively.
Answer» A piece of copper of mass 50g is drawn into a wire of length 50m.Find the resistance of the Wire . The density and Specific resistance Of Copper are 8.9 x 10^3 kg/m^3 and 1.7x10^-8 ohm-m restpectively.

Discussion

31.	What is the meaning of this sentence'' repulsive electrostatic force between protons should make a nucleus unstable''?
Answer» What is the meaning of this sentence'' repulsive electrostatic force between protons should make a nucleus unstable''?

Discussion

32.	An object O is kept 80 cm in front of a plane mirror M. If the mirror is moved 20 cm away from the object. Calculate the image shift from its previous position.
Answer» An object O is kept 80 cm in front of a plane mirror M. If the mirror is moved 20 cm away from the object. Calculate the image shift from its previous position.

Discussion

33.	ntAn electric motor operates on a 50 V supply and a current of 12 A.If the efficiency of the motor is 30 percentage.What is the resistance of the winding of the motor?n nta)6 ohmn ntb)4 ohmn ntc)2.9 ohmn ntd)3.1 ohmn
Answer» ntAn electric motor operates on a 50 V supply and a current of 12 A.If the efficiency of the motor is 30 percentage.What is the resistance of the winding of the motor?n nta)6 ohmn ntb)4 ohmn ntc)2.9 ohmn ntd)3.1 ohmn

Discussion

34.	In the given figure, find the potential of point M 1. 5V 2. –5V 3. 10V 4. –10V
Answer» In the given figure, find the potential of point M 1. 5V 2. –5V 3. 10V 4. –10V

Discussion

35.	What happens when we place a conductor or any medium inside an inductor?
Answer» What happens when we place a conductor or any medium inside an inductor?

Discussion

36.	The light form bathroom bulb gets dimmer for a moment when the geyser is switched on. Why?
Answer» The light form bathroom bulb gets dimmer for a moment when the geyser is switched on. Why?

Discussion

37.	at what depth below the earth's surface , the acceleration due to gravity will be half of the value of g on the earth's surface
Answer» at what depth below the earth's surface , the acceleration due to gravity will be half of the value of g on the earth's surface

Discussion

38.	When a charged particle enters a perpendicularly inward magnetic field then why a charge moves in a circular path?
Answer» When a charged particle enters a perpendicularly inward magnetic field then why a charge moves in a circular path?

Discussion

39.	A bulb emits light of wavelength 4500 ˚A. The bulb is rated as 150 W and 8% of the energy is emitted as light. How many photons are emitted by the bulb per second?
Answer» A bulb emits light of wavelength 4500 $˚ A$ . The bulb is rated as 150 W and 8% of the energy is emitted as light. How many photons are emitted by the bulb per second?

Discussion

40.	Why electrons revolve around nucleus and aren't simply get attracted by nucleus?
Answer» Why electrons revolve around nucleus and aren't simply get attracted by nucleus?

Discussion

41.	Four students recorded the readings of the potential difference by observing the position of the pointer of an ideal voltmeter as shown below:(1) 2.5 V(2) 2.0 V(3) 2.2 V(4) 2.4 V
Answer» Four students recorded the readings of the potential difference by observing the position of the pointer of an ideal voltmeter as shown below: (1) 2.5 V (2) 2.0 V (3) 2.2 V (4) 2.4 V

Discussion

42.	The observed magnetic bearing of a line OE was found to be 185∘. It was later discovered that station O had a local attraction of +1.5∘. The true bearing of the line OE, considering a magnetic declination of 3.5∘East shall be
Answer» The observed magnetic bearing of a line OE was found to be $185^{\circ}$ . It was later discovered that station O had a local attraction of $+ {1.5}^{\circ}$ . The true bearing of the line OE, considering a magnetic declination of ${3.5}^{\circ}$ East shall be

Discussion

43.	The electric flux across a rectangular surface of area A placed in uniform electric field (E) making angle 60° with its surface, isOptions:(1) 2EA(2) EA(3) √3EA/2(4) EA/2
Answer» The electric flux across a rectangular surface of area A placed in uniform electric field (E) making angle 60° with its surface, is Options: (1) 2EA (2) EA (3) √3EA/2 (4) EA/2

Discussion

44.	Imagine a new planet having the same density as that of earth but it is 3 times bigger than the earth in size If the acceleration due to gravity on the surface of earth is g and that on the surface of the new planet is g',then 1.g'=3g 2.g'=g/9 3.g'=9g 4.g'=27
Answer» Imagine a new planet having the same density as that of earth but it is 3 times bigger than the earth in size If the acceleration due to gravity on the surface of earth is g and that on the surface of the new planet is g',then 1.g'=3g 2.g'=g/9 3.g'=9g 4.g'=27

Discussion

45.	Periscope works on the principle of multiple reflection. It consists of two or more mirror, used for the reflection. If the two mirrors are placed at an angle of 90∘, how many images of the object are formed between them?
Answer» Periscope works on the principle of multiple reflection. It consists of two or more mirror, used for the reflection. If the two mirrors are placed at an angle of $90^{\circ}$ , how many images of the object are formed between them?

Discussion

46.	.A boy and a man carry a uniform rod of lengthL, horizontally in such a way that the boy getsth1/4 load. If the boy is at one end of the rod,the distance of the man from the other end is(E.A.M.C.E.T. 1986)(1) L/3(2) L/4(3) 2 L/3(4) 3 L/4
Answer» .A boy and a man carry a uniform rod of lengthL, horizontally in such a way that the boy getsth1/4 load. If the boy is at one end of the rod,the distance of the man from the other end is(E.A.M.C.E.T. 1986)(1) L/3(2) L/4(3) 2 L/3(4) 3 L/4

Discussion

47.	A particle having a charge 20 micro coulomb and mass 200 micro gram moves along a circle of radius 5cm under the action of a magnetic field B=1.0T. The kinetic energy of the particle
Answer» A particle having a charge 20 micro coulomb and mass 200 micro gram moves along a circle of radius 5cm under the action of a magnetic field B=1.0T. The kinetic energy of the particle

Discussion

48.	The picture shows a bucket being whirled around in a circle (neglect gravity). Think about the correlation between this action and the motion of the moon around the earth. Then pick out the incorrect statement.
Answer» The picture shows a bucket being whirled around in a circle (neglect gravity). Think about the correlation between this action and the motion of the moon around the earth. Then pick out the incorrect statement.

Discussion

49.	Can any source of energy be pollution free ? Explain your answer with an example.
Answer» Can any source of energy be pollution free ? Explain your answer with an example.

Discussion

50.	The strength of magnetic field inside a long current carrying solenoid is :
Answer» The strength of magnetic field inside a long current carrying solenoid is :

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

magnetic induction at centre point of axis of long solenoid is B. if length of solenoid is reduced to half and same wire is wound over it in 2 layers then new magnetic induction i

A cone of base radius R and height h is placed in an uniform electric field E which is parallel to base of cone . The electric flux entering the cone will b

Two equal positive charge Q are fixed at points (-a,0) and ( a,0 ) on the x axis .an opposite charge -q at the rest is released from point (0, a) on the y axis .the charge on -q will be

A small electric dipole is placed in x-y plane at origin with its dipole moment directed along positive x-axis. The direction of electric field at point (2,2/2, 0) is

Two identical small bodies each of mass m and charge q are suspended from 2 strings each of length l from a common fixed point in an orbiting artificial satellite, then the tension in strings will be

The refractive index of water is 43. The speed of light in water is: (Take the speed of light in air =3×108 ms−1)

Why electric current is a scalar quantity until and unless it has magnitude and direction both?

Show that if a ray of light is reflected successively from two mirrors inclined at an angle q, the deviation of the ray does not depend upon the angle of incidence.

A diver in a swimming pool wants to signal his distress to a person lying on the edge of the pool by flashing his water proof flash light

What are audible and inaudible sounds? What is the audibility frequency range for human ear?

Question 1 Define 1 dioptre of power of a lens.

Real, inverted and enlarged image will be formed in case of:

In the given circuit, the current through the 5 mH inductor, in steady state, will be -

The velocity of electron in the hydrogen atom is 2×10^6 m/s. The radius of orbit is 5×10^-11 m. The magnetic induction at the centre of orbit in tesla will be

With the help of a labeled diagram, explain why the sun appears reddish at the sun-rise and the sun-set.

How does the force of gravitation between two objects change when the distance between them is reduced to half?

Which of these steps when we incorporate in our life will helps us in consumption of resources in a sustainable manner.

Calculate the energy associated with the first orbit of he^+. What is the radius of this orbit?

Which kind of pattern do the musical notes follow?

An engine develops 10 kW of power. How much time will it take to lift a mass of 200 kg to a height of 40 m. (g=10m/sec2)

If a point charge is placed at the corner of cube then why we have taken fi total as q/8E

19. Expression for gravitational potential

(a) At what position a candle of length 3 cm be placed in front of a convex lens so that its image of length 6 cm be obtained on a screen placed at distance 30 cm behind the lens ? (b) What is the focal length of lens in part (a) ?

A capacitor is half filled with a dielectric (K = 2) as shown in figure A. If the same capacitor is to be filled with same dielectric as shown, what would be the thickness of dielectric so that capacitor still has same capacity ?

Calculate the kinetic energy of a body of mass 2 kg moving with a speed of 10ms−1.

A piece of copper of mass 50g is drawn into a wire of length 50m.Find the resistance of the Wire . The density and Specific resistance Of Copper are 8.9 x 10^3 kg/m^3 and 1.7x10^-8 ohm-m restpectively.

What is the meaning of this sentence'' repulsive electrostatic force between protons should make a nucleus unstable''?

An object O is kept 80 cm in front of a plane mirror M. If the mirror is moved 20 cm away from the object. Calculate the image shift from its previous position.

ntAn electric motor operates on a 50 V supply and a current of 12 A.If the efficiency of the motor is 30 percentage.What is the resistance of the winding of the motor?n nta)6 ohmn ntb)4 ohmn ntc)2.9 ohmn ntd)3.1 ohmn

In the given figure, find the potential of point M 1. 5V 2. –5V 3. 10V 4. –10V

What happens when we place a conductor or any medium inside an inductor?

The light form bathroom bulb gets dimmer for a moment when the geyser is switched on. Why?

at what depth below the earth's surface , the acceleration due to gravity will be half of the value of g on the earth's surface

When a charged particle enters a perpendicularly inward magnetic field then why a charge moves in a circular path?

A bulb emits light of wavelength 4500 ˚A. The bulb is rated as 150 W and 8% of the energy is emitted as light. How many photons are emitted by the bulb per second?

Why electrons revolve around nucleus and aren't simply get attracted by nucleus?

Four students recorded the readings of the potential difference by observing the position of the pointer of an ideal voltmeter as shown below:(1) 2.5 V(2) 2.0 V(3) 2.2 V(4) 2.4 V

The observed magnetic bearing of a line OE was found to be 185∘. It was later discovered that station O had a local attraction of +1.5∘. The true bearing of the line OE, considering a magnetic declination of 3.5∘East shall be

The electric flux across a rectangular surface of area A placed in uniform electric field (E) making angle 60° with its surface, isOptions:(1) 2EA(2) EA(3) √3EA/2(4) EA/2

Imagine a new planet having the same density as that of earth but it is 3 times bigger than the earth in size If the acceleration due to gravity on the surface of earth is g and that on the surface of the new planet is g',then 1.g'=3g 2.g'=g/9 3.g'=9g 4.g'=27

Periscope works on the principle of multiple reflection. It consists of two or more mirror, used for the reflection. If the two mirrors are placed at an angle of 90∘, how many images of the object are formed between them?

.A boy and a man carry a uniform rod of lengthL, horizontally in such a way that the boy getsth1/4 load. If the boy is at one end of the rod,the distance of the man from the other end is(E.A.M.C.E.T. 1986)(1) L/3(2) L/4(3) 2 L/3(4) 3 L/4

A particle having a charge 20 micro coulomb and mass 200 micro gram moves along a circle of radius 5cm under the action of a magnetic field B=1.0T. The kinetic energy of the particle

The picture shows a bucket being whirled around in a circle (neglect gravity). Think about the correlation between this action and the motion of the moon around the earth. Then pick out the incorrect statement.

Can any source of energy be pollution free ? Explain your answer with an example.

The strength of magnetic field inside a long current carrying solenoid is :