16569 + Interview Questions in Physics

1.	In the situation shown in the figure, three lenses of focal lengths, 20 cm,30 cm and 36 cm are held coaxial such that separation between first and second lens is 12 cm and between second and third lens is 10 cm. If the final image of an object at a distance of 30 cm from first lens is at a distance 10x cm from the middle lens, then the value of x is _______.
Answer» In the situation shown in the figure, three lenses of focal lengths, $20 cm, 30 cm$ and $36 cm$ are held coaxial such that separation between first and second lens is $12 cm$ and between second and third lens is $10 cm$ . If the final image of an object at a distance of $30 cm$ from first lens is at a distance $10 x cm$ from the middle lens, then the value of $x$ is _______.

Discussion

2.	34. The electric field part of an electromagnetic waves in vacuum is given by
Answer» 34. The electric field part of an electromagnetic waves in vacuum is given by

Discussion

3.	List some uses of copper in everyday life.
Answer» List some uses of copper in everyday life.

Discussion

4.	Name any one hydrocarbon fraction obtained during the fractional distillation of petroleum which is used as a domestic fuel.
Answer» Name any one hydrocarbon fraction obtained during the fractional distillation of petroleum which is used as a domestic fuel.

Discussion

5.	p-Orbitals in the absence of magnetic field are 1: Two-fold degenerate 2: Non-degenerate 3:Three-fold degenerate 4:Five-fold degenera
Answer» p-Orbitals in the absence of magnetic field are 1: Two-fold degenerate 2: Non-degenerate 3:Three-fold degenerate 4:Five-fold degenera

Discussion

6.	The equivalent resistance between the terminals A and B is Ω 3
Answer» The equivalent resistance between the terminals A and B is $Ω$ 3

Discussion

7.	What is the magnitude of magnetic field at the point P due to a current carrying wire of length 4 m and having a current of 4 A as shown in the figure? [μ0=4π×10−7 Tm/A]
Answer» What is the magnitude of magnetic field at the point P due to a current carrying wire of length 4 m and having a current of 4 A as shown in the figure? $[μ_{0} = 4 π \times 10^{- 7} T m / A]$

Discussion

8.	If flow of electrons causes heating of the circuit...then why does an air-conditioner stays cool and do not get heated at all when switched on...???
Answer» If flow of electrons causes heating of the circuit...then why does an air-conditioner stays cool and do not get heated at all when switched on...???

Discussion

9.	What is magnetic motor work
Answer» What is magnetic motor work

Discussion

10.	38.Two electric bulbs A and B rated 200V 100W and 200V 60W are connected in series to a 200V line.Then the potential drop across each bulb is?
Answer» 38.Two electric bulbs A and B rated 200V 100W and 200V 60W are connected in series to a 200V line.Then the potential drop across each bulb is?

Discussion

11.	No of electron in Ti with value of m as 1 and -1
Answer» No of electron in Ti with value of m as 1 and -1

Discussion

12.	If the force acting on a body of mass(2kg+-20g) is (3N+-2%) the maximum %age error in acceleration is
Answer» If the force acting on a body of mass(2kg+-20g) is (3N+-2%) the maximum %age error in acceleration is

Discussion

13.	Is there any relation between EMF of a battery and drift speed of electrons in the conductor connected to a battery?
Answer» Is there any relation between EMF of a battery and drift speed of electrons in the conductor connected to a battery?

Discussion

14.	Equivalent mass of o2 is
Answer» Equivalent mass of o2 is

Discussion

15.	The concave reflecting surface of a torch got rusted. What effect would this have on the beam of light from the torch?
Answer» The concave reflecting surface of a torch got rusted. What effect would this have on the beam of light from the torch?

Discussion

16.	why the resis†an ce is finite when current flows through the electrolytic solution
Answer» why the resis†an ce is finite when current flows through the electrolytic solution

Discussion

17.	Which of the following statements is NOT true about electromagnetic waves?
Answer» Which of the following statements is NOT true about electromagnetic waves?

Discussion

18.	Please elaborate and explain me clearly based on the below statement: "If there is a circular coil having n turns, the field produced is n times as large as that produced by a single turn. This is because the current in each circular turn has the same direction, and the field due to each turn then just adds up"
Answer» Please elaborate and explain me clearly based on the below statement: "If there is a circular coil having n turns, the field produced is n times as large as that produced by a single turn. This is because the current in each circular turn has the same direction, and the field due to each turn then just adds up"

Discussion

19.	In the video for "The Idea of Potential", sir says that even when water is static and in a bottle,, water is flowing due to Brownian motion but I don't think so as when water flows it moves collectively but during molecular motion the individual molecules are moving. So even if static and in a bottle is water really flowing?
Answer» In the video for "The Idea of Potential", sir says that even when water is static and in a bottle,, water is flowing due to Brownian motion but I don't think so as when water flows it moves collectively but during molecular motion the individual molecules are moving. So even if static and in a bottle is water really flowing?

Discussion

20.	in a uniform electric field if a charge is fired in a direction different from the line of electric field then the trajectory of charge will be1. circle2.straight line3. parabola4.ellipse
Answer» in a uniform electric field if a charge is fired in a direction different from the line of electric field then the trajectory of charge will be 1. circle 2.straight line 3. parabola 4.ellipse

20.

in a uniform electric field if a charge is fired in a direction different from the line of electric field then the trajectory of charge will be1. circle2.straight line3. parabola4.ellipse

Answer»

in a uniform electric field if a charge is fired in a direction different from the line of electric field then the trajectory of charge will be

1. circle

2.straight line

3. parabola

4.ellipse

Discussion

21.	Q 8) 250 g of water at 30 degree celsius is contained in a copper vessel of mass 50g.Calculate the mass of ice required to bring down the temperature of the vessel and its contents to 5 degeree celsius.Specific latent heat of fusion of ice 336*1000 J per kg. Specific heat capacity of copper =400 J per kg per K Specific heat Capacity of water =4200J per kg per K.
Answer» Q 8) 250 g of water at 30 degree celsius is contained in a copper vessel of mass 50g.Calculate the mass of ice required to bring down the temperature of the vessel and its contents to 5 degeree celsius.Specific latent heat of fusion of ice 336*1000 J per kg. Specific heat capacity of copper =400 J per kg per K Specific heat Capacity of water =4200J per kg per K.

21.

Q 8) 250 g of water at 30 degree celsius is contained in a copper vessel of mass 50g.Calculate the mass of ice required to bring down the temperature of the vessel and its contents to 5 degeree celsius.Specific latent heat of fusion of ice 336*1000 J per kg. Specific heat capacity of copper =400 J per kg per K Specific heat Capacity of water =4200J per kg per K.

Answer»

Q 8)

250 g of water at 30 degree celsius is contained in a copper vessel of mass 50g.Calculate the mass of ice required to bring down the temperature of the vessel and its contents to 5 degeree celsius.Specific latent heat of fusion of ice 336*1000 J per kg.

Specific heat capacity of copper =400 J per kg per K Specific heat Capacity of water =4200J per kg per K.

Discussion

22.	The frequencies 200 203 207hz are sounded together. Find out the beat frequency.
Answer» The frequencies 200 203 207hz are sounded together. Find out the beat frequency.

Discussion

23.	Alternating voltage is generated by rotating coil in a magnetic field with 50Hz frequency. If rms voltage is 220V, then maximum flux passing through the coil is(1)0.99 (2)0.4 (3)0.6 (4)0.7
Answer» Alternating voltage is generated by rotating coil in a magnetic field with 50Hz frequency. If rms voltage is 220V, then maximum flux passing through the coil is (1)0.99 (2)0.4 (3)0.6 (4)0.7

Discussion

24.	The orbital angular momentum of electron in 4s orbital is
Answer» The orbital angular momentum of electron in 4s orbital is

Discussion

25.	In Fig. 4.63, PQ and PR are the two light rays emerging from an object P. The ray PQ is refracted as QS. (a) State the special name given to the angle of incidence ∠PQN of the ray PQ. (b) What is the angle of refraction for the refracted ray QS? (c) Name the phenomenon that occurs if the angle of incidence ∠PQN is increased. (d) The ray PR suffers partial reflection and refraction on the water-air surface. Give reason. (e) Draw in the diagram the refracted ray for the incident ray PR and hence show the position of image of the object P by the letter P' when seen vertically from above.
Answer» In Fig. 4.63, PQ and PR are the two light rays emerging from an object P. The ray PQ is refracted as QS. (a) State the special name given to the angle of incidence $∠ P Q N$ of the ray PQ. (b) What is the angle of refraction for the refracted ray QS? (c) Name the phenomenon that occurs if the angle of incidence $∠ P Q N$ is increased. (d) The ray PR suffers partial reflection and refraction on the water-air surface. Give reason. (e) Draw in the diagram the refracted ray for the incident ray PR and hence show the position of image of the object P by the letter P' when seen vertically from above.

25.

In Fig. 4.63, PQ and PR are the two light rays emerging from an object P. The ray PQ is refracted as QS. (a) State the special name given to the angle of incidence ∠PQN of the ray PQ. (b) What is the angle of refraction for the refracted ray QS? (c) Name the phenomenon that occurs if the angle of incidence ∠PQN is increased. (d) The ray PR suffers partial reflection and refraction on the water-air surface. Give reason. (e) Draw in the diagram the refracted ray for the incident ray PR and hence show the position of image of the object P by the letter P' when seen vertically from above.

Answer»

In Fig. 4.63, PQ and PR are the two light rays emerging from an object P. The ray PQ is refracted as QS.

(a) State the special name given to the angle of incidence $∠ P Q N$ of the ray PQ.

(b) What is the angle of refraction for the refracted ray QS?

(c) Name the phenomenon that occurs if the angle of incidence $∠ P Q N$ is increased.

(d) The ray PR suffers partial reflection and refraction on the water-air surface. Give reason.

(e) Draw in the diagram the refracted ray for the incident ray PR and hence show the position of image of the object P by the letter P' when seen vertically from above.

Discussion

26.	what is spherical aberration and optical instruments?
Answer» what is spherical aberration and optical instruments?

Discussion

27.	A steel cable,by which an elevator of mass 800kg is suspended,has diameter of 2 cm.The unstretched length of the suspension cable is 10 m when the elevator is on the top floor of the building.The first floor is 50 m below the top floor. Find the values of extension in cable when the elevator is on the top and first floor. Ysteel=2×10¹¹ N/m²(g=9.8m/s²).
Answer» A steel cable,by which an elevator of mass 800kg is suspended,has diameter of 2 cm.The unstretched length of the suspension cable is 10 m when the elevator is on the top floor of the building.The first floor is 50 m below the top floor. Find the values of extension in cable when the elevator is on the top and first floor. Ysteel=2×10¹¹ N/m²(g=9.8m/s²).

Discussion

28.	Find the resistance between terminals A and B of the infinite network shown in the diagram, each resistance has the same value r?
Answer» Find the resistance between terminals A and B of the infinite network shown in the diagram, each resistance has the same value r?

Discussion

29.	105.Calculate the resistance of a 1Km long copper wire of area of cross section 2x10-2 cm2.The resistivity of copper is 1.623x10-8 ohm meter
Answer» 105.Calculate the resistance of a 1Km long copper wire of area of cross section 2x10-2 cm2.The resistivity of copper is 1.623x10-8 ohm meter

Discussion

30.	4.) The diameter of aperture of a plano-convex lens is 6 cm and its maximum thickness is 3 mm. If the velocity of light in the material of the lens is 2 x 108 m/s, its focal length is (approximately) (1) 10 cm (2) 15 cm (4) 60 cm La 30 cm
Answer» 4.) The diameter of aperture of a plano-convex lens is 6 cm and its maximum thickness is 3 mm. If the velocity of light in the material of the lens is 2 x 108 m/s, its focal length is (approximately) (1) 10 cm (2) 15 cm (4) 60 cm La 30 cm

Discussion

31.	Fuel formed under the earth's surface by the decomposition of organic matter is called _____.
Answer» Fuel formed under the earth's surface by the decomposition of organic matter is called _____.

Discussion

32.	Ray diagram for two lenses kept ar a some distance given in diagram, which of the following option is correct(f1,f2=focal lenghth, d=distance between two lenses) (1) f1 +f2> d (2) f1+f2
Answer» Ray diagram for two lenses kept ar a some distance given in diagram, which of the following option is correct(f1,f2=focal lenghth, d=distance between two lenses) (1) f1 +f2> d (2) f1+f2

Discussion

33.	31.The motion of a charged particle can be used to distinguish between a magnetic field and electric field in a certain region by firing the charge (1) perpendicular to the field (2) parallel to the field (3) from opposite directions (4) with different speeds
Answer» 31.The motion of a charged particle can be used to distinguish between a magnetic field and electric field in a certain region by firing the charge (1) perpendicular to the field (2) parallel to the field (3) from opposite directions (4) with different speeds

Discussion

34.	What adjustments should you make for tuning stringed instruments to emit a note of desired frequency?
Answer» What adjustments should you make for tuning stringed instruments to emit a note of desired frequency?

Discussion

35.	Why there is need to change the direction current in electic motor when the coil is rotate at 90 degrees.
Answer» Why there is need to change the direction current in electic motor when the coil is rotate at 90 degrees.

Discussion

36.	43.What is meant by relative humidity and give it's formula?
Answer» 43.What is meant by relative humidity and give it's formula?

Discussion

37.	A gear system has one wheel ‘A’ with 10 teeth and other wheel ‘B’ with 50 teeth. What is the action of the gear system in each case if the motor connected to: (i) wheel A (ii) wheel B.
Answer» A gear system has one wheel ‘A’ with 10 teeth and other wheel ‘B’ with 50 teeth. What is the action of the gear system in each case if the motor connected to: (i) wheel A (ii) wheel B.

37.

A gear system has one wheel ‘A’ with 10 teeth and other wheel ‘B’ with 50 teeth. What is the action of the gear system in each case if the motor connected to: (i) wheel A (ii) wheel B.

Answer»

A gear system has one wheel ‘A’ with 10 teeth and other wheel ‘B’ with 50 teeth. What is the action of the gear system in each case if the motor connected to:

(i) wheel A (ii) wheel B.

Discussion

38.	A thin convex lens of focal length 20cm is cut into two pieces. The top part is placed 0.5cm above the principal axis and an object is placed at {(-40, O). The coordinate of final image will be (Al position are in cm )
Answer» A thin convex lens of focal length 20cm is cut into two pieces. The top part is placed 0.5cm above the principal axis and an object is placed at {(-40, O). The coordinate of final image will be (Al position are in cm )

Discussion

39.	A burning candle whose flame is 1.5 cm tall is placed at a certain distance in front of a convex lens. An image of candle flame is received on a white screen kept behind the lens. The image of flame also measures 1.5 cm. If f is the focal length of convex lens, the candle is placed : (a) at f (b) between f and 2f (c) at 2f (d) beyond 2f
Answer» A burning candle whose flame is 1.5 cm tall is placed at a certain distance in front of a convex lens. An image of candle flame is received on a white screen kept behind the lens. The image of flame also measures 1.5 cm. If f is the focal length of convex lens, the candle is placed : (a) at f (b) between f and 2f (c) at 2f (d) beyond 2f

Discussion

40.	Watt is the SI unit of power, is also a unit by which electrical power can be represented.
Answer» Watt is the SI unit of power, is also a unit by which electrical power can be represented.

Discussion

41.	If the shape of the rainbow is circular, why are we unable to see the whole circle?
Answer» If the shape of the rainbow is circular, why are we unable to see the whole circle?

Discussion

42.	A man standing in front of a special mirror finds his image having a very small head, a fat body and legs of normal size. The shapes of the three parts of the special mirror are
Answer» A man standing in front of a special mirror finds his image having a very small head, a fat body and legs of normal size. The shapes of the three parts of the special mirror are

Discussion

43.	Explain why planets do not twinkle at night.
Answer» Explain why planets do not twinkle at night.

Discussion

44.	Two resistance X and Y are connected turn by turn : (i) in parallel, and (ii) in series. In which case the resultant resistance will be less than either of the individual resistances?
Answer» Two resistance X and Y are connected turn by turn : (i) in parallel, and (ii) in series. In which case the resultant resistance will be less than either of the individual resistances?

Discussion

45.	A astronomical telescope has objective and eyepiece of focal lenghts 40 cm 4 cm respectively. To view an object 200 cm away from the objectiv, the lenses must be speparted by a distance.
Answer» A astronomical telescope has objective and eyepiece of focal lenghts 40 cm 4 cm respectively. To view an object 200 cm away from the objectiv, the lenses must be speparted by a distance.

Discussion

46.	16. Calculate the value of acceleration due to gravity on the surface of the planet Jupiter . mass of a Jupiter is 319 times of the mass of the earth .radius of the Jupiter is 11.2 times the radius of Earth
Answer» 16. Calculate the value of acceleration due to gravity on the surface of the planet Jupiter . mass of a Jupiter is 319 times of the mass of the earth .radius of the Jupiter is 11.2 times the radius of Earth

Discussion

47.	The maximum angular magnification produced by an astronomical telescope is 30. Find the focal length of objective lens, if the focal length of eyepiece is 12.5 cm.
Answer» The maximum angular magnification produced by an astronomical telescope is $30$ . Find the focal length of objective lens, if the focal length of eyepiece is $12.5 cm$ .

Discussion

48.	Which out of the following statements is a characteristic of an alpha particle? I. It is positively charged. II. It has no mass or charge. III. It's symbol is 0−1e. IV. It has poor penetrating ability.
Answer» Which out of the following statements is a characteristic of an alpha particle? I. It is positively charged. II. It has no mass or charge. III. It's symbol is $_{- 1}^{0} e$ . IV. It has poor penetrating ability.

48.

Which out of the following statements is a characteristic of an alpha particle? I. It is positively charged. II. It has no mass or charge. III. It's symbol is 0−1e. IV. It has poor penetrating ability.

Answer»

Which out of the following statements is a characteristic of an alpha particle?

I. It is positively charged.

II. It has no mass or charge.

III. It's symbol is $_{- 1}^{0} e$ .

IV. It has poor penetrating ability.

Discussion

49.	Draw a labelled diagram of an electric motor. Explain its principle and working. What is the function of a split ring in an electric motor?
Answer» Draw a labelled diagram of an electric motor. Explain its principle and working. What is the function of a split ring in an electric motor?

Discussion

50.	a metal rod ata atemperature of 150 degree centigrade radiates energy at a rate of 20 watt. if its temperature is increased to 300 degree centigrade then what amount of energy it will radiate per unit second?a. 40.8 wattb. 17.5c. 68.3d. 37.2
Answer» a metal rod ata atemperature of 150 degree centigrade radiates energy at a rate of 20 watt. if its temperature is increased to 300 degree centigrade then what amount of energy it will radiate per unit second?a. 40.8 wattb. 17.5c. 68.3d. 37.2

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

34. The electric field part of an electromagnetic waves in vacuum is given by

List some uses of copper in everyday life.

Name any one hydrocarbon fraction obtained during the fractional distillation of petroleum which is used as a domestic fuel.

p-Orbitals in the absence of magnetic field are 1: Two-fold degenerate 2: Non-degenerate 3:Three-fold degenerate 4:Five-fold degenera

The equivalent resistance between the terminals A and B is Ω 3

What is the magnitude of magnetic field at the point P due to a current carrying wire of length 4 m and having a current of 4 A as shown in the figure? [μ0=4π×10−7 Tm/A]

If flow of electrons causes heating of the circuit...then why does an air-conditioner stays cool and do not get heated at all when switched on...???

What is magnetic motor work

38.Two electric bulbs A and B rated 200V 100W and 200V 60W are connected in series to a 200V line.Then the potential drop across each bulb is?

No of electron in Ti with value of m as 1 and -1

If the force acting on a body of mass(2kg+-20g) is (3N+-2%) the maximum %age error in acceleration is

Is there any relation between EMF of a battery and drift speed of electrons in the conductor connected to a battery?

Equivalent mass of o2 is

The concave reflecting surface of a torch got rusted. What effect would this have on the beam of light from the torch?

why the resis†an ce is finite when current flows through the electrolytic solution

Which of the following statements is NOT true about electromagnetic waves?

in a uniform electric field if a charge is fired in a direction different from the line of electric field then the trajectory of charge will be1. circle2.straight line3. parabola4.ellipse

The frequencies 200 203 207hz are sounded together. Find out the beat frequency.

Alternating voltage is generated by rotating coil in a magnetic field with 50Hz frequency. If rms voltage is 220V, then maximum flux passing through the coil is(1)0.99 (2)0.4 (3)0.6 (4)0.7

The orbital angular momentum of electron in 4s orbital is

what is spherical aberration and optical instruments?

Find the resistance between terminals A and B of the infinite network shown in the diagram, each resistance has the same value r?

105.Calculate the resistance of a 1Km long copper wire of area of cross section 2x10-2 cm2.The resistivity of copper is 1.623x10-8 ohm meter

4.) The diameter of aperture of a plano-convex lens is 6 cm and its maximum thickness is 3 mm. If the velocity of light in the material of the lens is 2 x 108 m/s, its focal length is (approximately) (1) 10 cm (2) 15 cm (4) 60 cm La 30 cm

Fuel formed under the earth's surface by the decomposition of organic matter is called _____.

Ray diagram for two lenses kept ar a some distance given in diagram, which of the following option is correct(f1,f2=focal lenghth, d=distance between two lenses) (1) f1 +f2> d (2) f1+f2

31.The motion of a charged particle can be used to distinguish between a magnetic field and electric field in a certain region by firing the charge (1) perpendicular to the field (2) parallel to the field (3) from opposite directions (4) with different speeds

What adjustments should you make for tuning stringed instruments to emit a note of desired frequency?

Why there is need to change the direction current in electic motor when the coil is rotate at 90 degrees.

43.What is meant by relative humidity and give it's formula?

A gear system has one wheel ‘A’ with 10 teeth and other wheel ‘B’ with 50 teeth. What is the action of the gear system in each case if the motor connected to: (i) wheel A (ii) wheel B.

A thin convex lens of focal length 20cm is cut into two pieces. The top part is placed 0.5cm above the principal axis and an object is placed at {(-40, O). The coordinate of final image will be (Al position are in cm )

Watt is the SI unit of power, is also a unit by which electrical power can be represented.

If the shape of the rainbow is circular, why are we unable to see the whole circle?

A man standing in front of a special mirror finds his image having a very small head, a fat body and legs of normal size. The shapes of the three parts of the special mirror are

Explain why planets do not twinkle at night.

Two resistance X and Y are connected turn by turn : (i) in parallel, and (ii) in series. In which case the resultant resistance will be less than either of the individual resistances?

A astronomical telescope has objective and eyepiece of focal lenghts 40 cm 4 cm respectively. To view an object 200 cm away from the objectiv, the lenses must be speparted by a distance.

16. Calculate the value of acceleration due to gravity on the surface of the planet Jupiter . mass of a Jupiter is 319 times of the mass of the earth .radius of the Jupiter is 11.2 times the radius of Earth

The maximum angular magnification produced by an astronomical telescope is 30. Find the focal length of objective lens, if the focal length of eyepiece is 12.5 cm.

Which out of the following statements is a characteristic of an alpha particle? I. It is positively charged. II. It has no mass or charge. III. It's symbol is 0−1e. IV. It has poor penetrating ability.

Draw a labelled diagram of an electric motor. Explain its principle and working. What is the function of a split ring in an electric motor?

a metal rod ata atemperature of 150 degree centigrade radiates energy at a rate of 20 watt. if its temperature is increased to 300 degree centigrade then what amount of energy it will radiate per unit second?a. 40.8 wattb. 17.5c. 68.3d. 37.2