16569 + Interview Questions in Physics

1.	A conducting wire has electric resistance ‘R′. If the length of this wire and the area of the cross-section are halved, then what will be the new resistance of the wire?
Answer» A conducting wire has electric resistance $‘ R^{'}$ . If the length of this wire and the area of the cross-section are halved, then what will be the new resistance of the wire?

Discussion

2.	when the angle of incidence is 60degree on the surface of a glass slab, it is found that reflected ray iscompletely polarised. the velocity of light in glass i
Answer» when the angle of incidence is 60degree on the surface of a glass slab, it is found that reflected ray iscompletely polarised. the velocity of light in glass i

Discussion

3.	Which is more stable .Mn2+ or Cr3+
Answer» Which is more stable .Mn2+ or Cr3+

Discussion

4.	1.what type of concave lens is present in the spectacles of a person with minus power?Is it convexo concavo lens ,plano concavo or double concave lens?
Answer» 1.what type of concave lens is present in the spectacles of a person with minus power?Is it convexo concavo lens ,plano concavo or double concave lens?

Discussion

5.	24 identical cells each of e.m.f 2volt and internal resis†an ce 2Ω are arranged to send maximum current through an external resis†an ce of 3Ω. the maximum current throgh the external resis†an ce is
Answer» 24 identical cells each of e.m.f 2volt and internal resis†an ce 2Ω are arranged to send maximum current through an external resis†an ce of 3Ω. the maximum current throgh the external resis†an ce is

Discussion

6.	In the experiment to find emf of 2 cells in potentiometer to which terminal of galvanometer is the jockey connected positive or negative?
Answer» In the experiment to find emf of 2 cells in potentiometer to which terminal of galvanometer is the jockey connected positive or negative?

Discussion

7.	Find the current through the 10 Ω resistor shown in figure.
Answer» Find the current through the $10 Ω$ resistor shown in figure.

Discussion

8.	A current 3 A flows through 2 Ω resistor as shown in the circuit. The power dissipated in the 5 Ω resistor is
Answer» A current $3 A$ flows through $2 Ω$ resistor as shown in the circuit. The power dissipated in the $5 Ω$ resistor is

Discussion

9.	For the given power output, there exists two values of external resistance, the product of these resistances will be equal to
Answer» For the given power output, there exists two values of external resistance, the product of these resistances will be equal to

Discussion

10.	You are given three resistors of 2 ohms, 4 ohms, and 6 ohms. With the help of these resistors, how can you get a resultant resistance of (i) 12 ohms, and (ii) 3 ohms?Draw diagrams to illustrate your answer.
Answer» You are given three resistors of 2 ohms, 4 ohms, and 6 ohms. With the help of these resistors, how can you get a resultant resistance of (i) 12 ohms, and (ii) 3 ohms? Draw diagrams to illustrate your answer.

Discussion

11.	In which of the following, scattering of light is not involved?
Answer» In which of the following, scattering of light is not involved?

Discussion

12.	a second harmonic has to be genarated in a string of length l streatched beteen two supports.the point where the string has to be plucked and touched ar
Answer» a second harmonic has to be genarated in a string of length l streatched beteen two supports.the point where the string has to be plucked and touched ar

Discussion

13.	The magnetic field at the centre of a current carrying circular coil of radius 10 cm is 5√5 times the magnetic field at a point on its axis. The distance of the point from the centre of the coil is ( Kindly explain each step )(x² + R²) ^3/2 = 5√5 R³ specially this one
Answer» The magnetic field at the centre of a current carrying circular coil of radius 10 cm is 5√5 times the magnetic field at a point on its axis. The distance of the point from the centre of the coil is ( Kindly explain each step ) (x² + R²) ^3/2 = 5√5 R³ specially this one

Discussion

14.	Question 13 (c)A coil of insulated copper wire is connected to a galvanometer. What will happen if a bar magnet is(iii) held stationary inside the coil?
Answer» Question 13 (c) A coil of insulated copper wire is connected to a galvanometer. What will happen if a bar magnet is (iii) held stationary inside the coil?

Discussion

15.	A long solenoid having n turns per unit length and current I. If radius of each turn is R, then magnetic moment per unit length
Answer» A long solenoid having n turns per unit length and current I. If radius of each turn is R, then magnetic moment per unit length

Discussion

16.	An uncontrolled nuclear chain reaction forms the basis of : (a) nuclear power plant (b) hydrogen bomb (c) thermal power station (d) atom bomb
Answer» An uncontrolled nuclear chain reaction forms the basis of : (a) nuclear power plant (b) hydrogen bomb (c) thermal power station (d) atom bomb

Discussion

17.	A torch bulb is rated 2.5V and 750mA. Two identical resistors, each of resistance 2 ohm , are connected in series and parallel to a battery of 12 V Calculate ratio of power consumed in two cases.
Answer» A torch bulb is rated 2.5V and 750mA. Two identical resistors, each of resistance 2 ohm , are connected in series and parallel to a battery of 12 V Calculate ratio of power consumed in two cases.

Discussion

18.	focal length of objective eye piece an inverting lens of terrestrial telescope are 20 cm , 10 cm , 5 cm respectively . length of the tube containing these lenses at normal adjustment is(1) 30 cm (2) 35 cm (3) 50 cm (4) 40 cm
Answer» focal length of objective eye piece an inverting lens of terrestrial telescope are 20 cm , 10 cm , 5 cm respectively . length of the tube containing these lenses at normal adjustment is (1) 30 cm (2) 35 cm (3) 50 cm (4) 40 cm

Discussion

19.	A particle P is formed due to a completely inelastic collision of particles x and y having de - Broglie wavelengths λx and λy respectively. If x and y were moving in opposite directions, then the de-Broglie wavelength of P is :
Answer» A particle $P$ is formed due to a completely inelastic collision of particles $x$ and $y$ having de - Broglie wavelengths $λ_{x}$ and $λ_{y}$ respectively. If $x$ and $y$ were moving in opposite directions, then the de-Broglie wavelength of $P$ is :

Discussion

20.	What kind of mirror-concave, convex or plane-would be best suited for use in a solar cooker? Why?
Answer» What kind of mirror-concave, convex or plane-would be best suited for use in a solar cooker? Why?

Discussion

21.	Consider the circuit shown below where all resistors are of 1 k ΩIf a current of magnitude 1 mA flows through the resistor marked X, what is the potential difference measured between point P and Q?
Answer» Consider the circuit shown below where all resistors are of 1 k $Ω$ If a current of magnitude 1 mA flows through the resistor marked X, what is the potential difference measured between point P and Q?

21.

Consider the circuit shown below where all resistors are of 1 k ΩIf a current of magnitude 1 mA flows through the resistor marked X, what is the potential difference measured between point P and Q?

Answer»

Consider the circuit shown below where all resistors are of 1 k $Ω$

If a current of magnitude 1 mA flows through the resistor marked X, what is the potential difference measured between point P and Q?

Discussion

22.	A telescope has an objective lens of focal length 200cm and an eye piece with focal length 2cm. If thistelescope is used to see a 50 meter tall building ata distance of 2km, what is the height of the imageof the building formed by the objective lens(1) 5 cm(2) 10 cm(4) 2 cm(3) 1 cm
Answer» A telescope has an objective lens of focal length 200cm and an eye piece with focal length 2cm. If thistelescope is used to see a 50 meter tall building ata distance of 2km, what is the height of the imageof the building formed by the objective lens(1) 5 cm(2) 10 cm(4) 2 cm(3) 1 cm

Discussion

23.	The temperature difference between the upper layers and the deeper layers of the ocean should be ______ to install an OTEC power plant.
Answer» The temperature difference between the upper layers and the deeper layers of the ocean should be ______ to install an OTEC power plant.

Discussion

24.	What is Tyndall Effect? [2 MARKS]
Answer» What is Tyndall Effect? [2 MARKS]

Discussion

25.	Two metallic wires A and B are connected in parallel. Wire A has length l and radius r, wire B has a length 2l and radius 2r. Compute the ratio of the total resistance of parallel combination and the resistance of wire A.
Answer» Two metallic wires A and B are connected in parallel. Wire A has length l and radius r, wire B has a length 2l and radius 2r. Compute the ratio of the total resistance of parallel combination and the resistance of wire A.

Discussion

26.	An object is placed at a distance of 10 cm from a convex mirror of focal length 5cm.Calculate the distance of an image from mirror.
Answer» An object is placed at a distance of 10 cm from a convex mirror of focal length 5cm. Calculate the distance of an image from mirror.

Discussion

27.	aqueous solution of Znso4 is electrolysed by passing current of 965 ampere for 100s , using inert electrode then total volume of gases liberated at electrode
Answer» aqueous solution of Znso4 is electrolysed by passing current of 965 ampere for 100s , using inert electrode then total volume of gases liberated at electrode

Discussion

28.	In a move that could provide some respite to ailing airline companies, the government is looking at allowing them to import jet fuel on their own. Which of the following can be definitely concluded from the above Paragraph?
Answer» In a move that could provide some respite to ailing airline companies, the government is looking at allowing them to import jet fuel on their own. Which of the following can be definitely concluded from the above Paragraph?

28.

In a move that could provide some respite to ailing airline companies, the government is looking at allowing them to import jet fuel on their own. Which of the following can be definitely concluded from the above Paragraph?

Answer»

In a move that could provide some respite to ailing airline companies, the government is looking at allowing them to import jet fuel on their own.

Which of the following can be definitely concluded from the above Paragraph?

Discussion

29.	Give scientific reasons:(1) The material used for fuse has low melting point.(2) Wood and glass are good insulators.(3) The melting point of filament of a bulb is very high.(4) Connecting wires in a circuit are made of copper and aluminum.
Answer» Give scientific reasons: (1) The material used for fuse has low melting point. (2) Wood and glass are good insulators. (3) The melting point of filament of a bulb is very high. (4) Connecting wires in a circuit are made of copper and aluminum.

29.

Give scientific reasons:(1) The material used for fuse has low melting point.(2) Wood and glass are good insulators.(3) The melting point of filament of a bulb is very high.(4) Connecting wires in a circuit are made of copper and aluminum.

Answer»

Give scientific reasons:

(1) The material used for fuse has low melting point.

(2) Wood and glass are good insulators.

(3) The melting point of filament of a bulb is very high.

(4) Connecting wires in a circuit are made of copper and aluminum.

Discussion

30.	When a soft iron core is introduced in a coil, the strength of the magnetic field:
Answer» When a soft iron core is introduced in a coil, the strength of the magnetic field:

Discussion

31.	Which of the following figures correctly represents the magnetic field lines due to a bar magnet?
Answer» Which of the following figures correctly represents the magnetic field lines due to a bar magnet?

Discussion

32.	The power of a lens is -4 D. Find the focal length and type of the lens?
Answer» The power of a lens is -4 D. Find the focal length and type of the lens?

Discussion

33.	A light and a heavy object have the same momentum. Find out the ratio of their kinetic energies. Which one has a larger kinetic energy?
Answer» A light and a heavy object have the same momentum. Find out the ratio of their kinetic energies. Which one has a larger kinetic energy?

Discussion

34.	Cosider a gravity - free hall in which a tray of mass M , carrying a cubical block of ice of mass m and edge L , is at rest in the middle. If the ice melts, by what distance does the centre of mass of "the tray plus the ice" system descent ?
Answer» Cosider a gravity - free hall in which a tray of mass M , carrying a cubical block of ice of mass m and edge L , is at rest in the middle. If the ice melts, by what distance does the centre of mass of "the tray plus the ice" system descent ?

34.

Cosider a gravity - free hall in which a tray of mass M , carrying a cubical block of ice of mass m and edge L , is at rest in the middle. If the ice melts, by what distance does the centre of mass of "the tray plus the ice" system descent ?

Answer»

Cosider a gravity - free hall in which a tray of mass M , carrying a cubical block of ice of mass m and edge L , is at rest in the middle. If the ice melts, by what distance does the centre of mass of "the tray plus the ice" system descent ?

Discussion

35.	The given figure shows a mixed source R of α−and β−particles in a thick lead container. The particles pass through a magnetic field in a direction perpendicular to the place of paper inwards as shown by ×. (a) State and show in the diagram how the particles get affected. (b) Why is the source R kept in a thick lead container? [5 MARKS]
Answer» The given figure shows a mixed source R of $α - a n d β - p a r t i c l e s$ in a thick lead container. The particles pass through a magnetic field in a direction perpendicular to the place of paper inwards as shown by $\times$ . (a) State and show in the diagram how the particles get affected. (b) Why is the source R kept in a thick lead container? [5 MARKS]

Discussion

36.	If a message signal of frequency fm is amplitude modulated with a carrier signal of frequency fc and radiated through an antenna , the wavelength of the corresponding signal in air is :[ Given , c = speed of electromagnetic wave in vacuum/air ]
Answer» If a message signal of frequency $f_{m}$ is amplitude modulated with a carrier signal of frequency $f_{c}$ and radiated through an antenna , the wavelength of the corresponding signal in air is : [ Given , $c$ = speed of electromagnetic wave in vacuum/air ]

Discussion

37.	When a convex lens is placed in between the object and the screen, and the object is at a distance of 45 cm from the screen by the convex lens, we obtain a small image of the object on the screen. By moving the lens, we receive a different image on the screen, whose size is 4 times greater than the first. The focal length of the convex lens is ( in cm )
Answer» When a convex lens is placed in between the object and the screen, and the object is at a distance of $45 cm$ from the screen by the convex lens, we obtain a small image of the object on the screen. By moving the lens, we receive a different image on the screen, whose size is $4$ times greater than the first. The focal length of the convex lens is ( in $cm$ )

Discussion

38.	Question 24What is the role of fuse, used in series with any electrical appliance? Why should a fuse with defined rating not be replaced by one with a larger rating?
Answer» Question 24 What is the role of fuse, used in series with any electrical appliance? Why should a fuse with defined rating not be replaced by one with a larger rating?

Discussion

39.	Which of the following is correct expression for acceleration due to gravity on surface of earth -(d is the density of earth and R is radius of earth)
Answer» Which of the following is correct expression for acceleration due to gravity on surface of earth - ( $d$ is the density of earth and $R$ is radius of earth)

Discussion

40.	Is one of the radius of curvature of a lens always negetive and one radius always positive ?
Answer» Is one of the radius of curvature of a lens always negetive and one radius always positive ?

Discussion

41.	What is watershed management? Write it's advantages.
Answer» What is watershed management? Write it's advantages.

Discussion

42.	Find the angle of incidence at which the light ray will retrace its path after reflection from the plane mirror.
Answer» Find the angle of incidence at which the light ray will retrace its path after reflection from the plane mirror.

Discussion

43.	By drawing a neat diagram, describe the image formation by a concave lens when an object is (a) at infinity. (b) anywhere between optical centre and infinity. [5 MARKS]
Answer» By drawing a neat diagram, describe the image formation by a concave lens when an object is (a) at infinity. (b) anywhere between optical centre and infinity. [5 MARKS]

Discussion

44.	An isolated charge 'Q' of mass 'm' is suspended freely by a thread of length 'l'. Another charge q is brought near it which is at distance ' r'( r>>l). When Q is in equilibrium, tension in thread will be
Answer» An isolated charge 'Q' of mass 'm' is suspended freely by a thread of length 'l'. Another charge q is brought near it which is at distance ' r'( r>>l). When Q is in equilibrium, tension in thread will be

Discussion

45.	What is the general name of the substances having infinitely high electrical resistance?
Answer» What is the general name of the substances having infinitely high electrical resistance?

Discussion

46.	Question 29We read in newspapers that burning of fuels is a major cause of global warming. Explain why.
Answer» Question 29 We read in newspapers that burning of fuels is a major cause of global warming. Explain why.

Discussion

47.	If the angle of incidence is half of the angle of refraction in a medium of refractive index mu relative to first medium, then the angle of incidence is
Answer» If the angle of incidence is half of the angle of refraction in a medium of refractive index mu relative to first medium, then the angle of incidence is

Discussion

48.	59.There is a non-conducting rod of length L and negligible mass with two small balls each of mass m and electric charge Q attached to its ends.the rod can rotate about a fixed vertical axis crossing it distance L/4 from one of its ends. A uniform horizontal electric field E is established. 1.At first the rod is in unstable equilibrium.If it is disturbed slightly in this position, the max velocity attained by the ball which is closer to the axis in subsequent motion is?
Answer» 59.There is a non-conducting rod of length L and negligible mass with two small balls each of mass m and electric charge Q attached to its ends.the rod can rotate about a fixed vertical axis crossing it distance L/4 from one of its ends. A uniform horizontal electric field E is established. 1.At first the rod is in unstable equilibrium.If it is disturbed slightly in this position, the max velocity attained by the ball which is closer to the axis in subsequent motion is?

Discussion

49.	Calculate the equivalent resistance of the diagram, if the value of every resistance is R
Answer» Calculate the equivalent resistance of the diagram, if the value of every resistance is R

Discussion

50.	Why is magnetic force much weaker than electric force ?
Answer» Why is magnetic force much weaker than electric force ?

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

A conducting wire has electric resistance ‘R′. If the length of this wire and the area of the cross-section are halved, then what will be the new resistance of the wire?

when the angle of incidence is 60degree on the surface of a glass slab, it is found that reflected ray iscompletely polarised. the velocity of light in glass i

Which is more stable .Mn2+ or Cr3+

1.what type of concave lens is present in the spectacles of a person with minus power?Is it convexo concavo lens ,plano concavo or double concave lens?

24 identical cells each of e.m.f 2volt and internal resis†an ce 2Ω are arranged to send maximum current through an external resis†an ce of 3Ω. the maximum current throgh the external resis†an ce is

In the experiment to find emf of 2 cells in potentiometer to which terminal of galvanometer is the jockey connected positive or negative?

Find the current through the 10 Ω resistor shown in figure.

A current 3 A flows through 2 Ω resistor as shown in the circuit. The power dissipated in the 5 Ω resistor is

For the given power output, there exists two values of external resistance, the product of these resistances will be equal to

You are given three resistors of 2 ohms, 4 ohms, and 6 ohms. With the help of these resistors, how can you get a resultant resistance of (i) 12 ohms, and (ii) 3 ohms?​Draw diagrams to illustrate your answer.

In which of the following, scattering of light is not involved?

a second harmonic has to be genarated in a string of length l streatched beteen two supports.the point where the string has to be plucked and touched ar

The magnetic field at the centre of a current carrying circular coil of radius 10 cm is 5√5 times the magnetic field at a point on its axis. The distance of the point from the centre of the coil is ( Kindly explain each step )(x² + R²) ^3/2 = 5√5 R³ specially this one

Question 13 (c)A coil of insulated copper wire is connected to a galvanometer. What will happen if a bar magnet is(iii) held stationary inside the coil?

A long solenoid having n turns per unit length and current I. If radius of each turn is R, then magnetic moment per unit length

An uncontrolled nuclear chain reaction forms the basis of : (a) nuclear power plant (b) hydrogen bomb (c) thermal power station (d) atom bomb

​​A torch bulb is rated 2.5V and 750mA. Two identical resistors, each of resistance 2 ohm , are connected in series and parallel to a battery of 12 V Calculate ratio of power consumed in two cases.

focal length of objective eye piece an inverting lens of terrestrial telescope are 20 cm , 10 cm , 5 cm respectively . length of the tube containing these lenses at normal adjustment is(1) 30 cm (2) 35 cm (3) 50 cm (4) 40 cm

A particle P is formed due to a completely inelastic collision of particles x and y having de - Broglie wavelengths λx and λy respectively. If x and y were moving in opposite directions, then the de-Broglie wavelength of P is :

What kind of mirror-concave, convex or plane-would be best suited for use in a solar cooker? Why?

Consider the circuit shown below where all resistors are of 1 k ΩIf a current of magnitude 1 mA flows through the resistor marked X, what is the potential difference measured between point P and Q?

A telescope has an objective lens of focal length 200cm and an eye piece with focal length 2cm. If thistelescope is used to see a 50 meter tall building ata distance of 2km, what is the height of the imageof the building formed by the objective lens(1) 5 cm(2) 10 cm(4) 2 cm(3) 1 cm

The temperature difference between the upper layers and the deeper layers of the ocean should be ______ to install an OTEC power plant.

What is Tyndall Effect? [2 MARKS]

Two metallic wires A and B are connected in parallel. Wire A has length l and radius r, wire B has a length 2l and radius 2r. Compute the ratio of the total resistance of parallel combination and the resistance of wire A.

An object is placed at a distance of 10 cm from a convex mirror of focal length 5cm.Calculate the distance of an image from mirror.

aqueous solution of Znso4 is electrolysed by passing current of 965 ampere for 100s , using inert electrode then total volume of gases liberated at electrode

In a move that could provide some respite to ailing airline companies, the government is looking at allowing them to import jet fuel on their own. Which of the following can be definitely concluded from the above Paragraph?

Give scientific reasons:(1) The material used for fuse has low melting point.(2) Wood and glass are good insulators.(3) The melting point of filament of a bulb is very high.(4) Connecting wires in a circuit are made of copper and aluminum.

When a soft iron core is introduced in a coil, the strength of the magnetic field:

Which of the following figures correctly represents the magnetic field lines due to a bar magnet?

The power of a lens is -4 D. Find the focal length and type of the lens?

A light and a heavy object have the same momentum. Find out the ratio of their kinetic energies. Which one has a larger kinetic energy?

Cosider a gravity - free hall in which a tray of mass M , carrying a cubical block of ice of mass m and edge L , is at rest in the middle. If the ice melts, by what distance does the centre of mass of "the tray plus the ice" system descent ?

If a message signal of frequency fm is amplitude modulated with a carrier signal of frequency fc and radiated through an antenna , the wavelength of the corresponding signal in air is :[ Given , c = speed of electromagnetic wave in vacuum/air ]

Question 24What is the role of fuse, used in series with any electrical appliance? Why should a fuse with defined rating not be replaced by one with a larger rating?

Which of the following is correct expression for acceleration due to gravity on surface of earth -(d is the density of earth and R is radius of earth)

Is one of the radius of curvature of a lens always negetive and one radius always positive ?

What is watershed management? Write it's advantages.

Find the angle of incidence at which the light ray will retrace its path after reflection from the plane mirror.

By drawing a neat diagram, describe the image formation by a concave lens when an object is (a) at infinity. (b) anywhere between optical centre and infinity. [5 MARKS]

An isolated charge 'Q' of mass 'm' is suspended freely by a thread of length 'l'. Another charge q is brought near it which is at distance ' r'( r>>l). When Q is in equilibrium, tension in thread will be

What is the general name of the substances having infinitely high electrical resistance?

Question 29We read in newspapers that burning of fuels is a major cause of global warming. Explain why.

If the angle of incidence is half of the angle of refraction in a medium of refractive index mu relative to first medium, then the angle of incidence is

Calculate the equivalent resistance of the diagram, if the value of every resistance is R

Why is magnetic force much weaker than electric force ? ​​​​​

You are given three resistors of 2 ohms, 4 ohms, and 6 ohms. With the help of these resistors, how can you get a resultant resistance of (i) 12 ohms, and (ii) 3 ohms?Draw diagrams to illustrate your answer.

A torch bulb is rated 2.5V and 750mA. Two identical resistors, each of resistance 2 ohm , are connected in series and parallel to a battery of 12 V Calculate ratio of power consumed in two cases.

Why is magnetic force much weaker than electric force ?