16569 + Interview Questions in Physics

1.	A wire of length 0.24 m and diameter 3.0×10−5 m has a resistance of 160Ω. Calculate the resistivity of the material.?
Answer» A wire of length 0.24 m and diameter $3.0 \times 10^{- 5}$ m has a resistance of $160 Ω$ . Calculate the resistivity of the material.?

Discussion

2.	What is furnace?
Answer» What is furnace?

Discussion

3.	What is hypermetropia? State the two causes. With the help of labelled ray diagram, show (i) Eye defect (ii) Correction of Hypermetropia
Answer» What is hypermetropia? State the two causes. With the help of labelled ray diagram, show (i) Eye defect (ii) Correction of Hypermetropia

3.

What is hypermetropia? State the two causes. With the help of labelled ray diagram, show (i) Eye defect (ii) Correction of Hypermetropia

Answer»

What is hypermetropia? State the two causes. With the help of labelled ray diagram, show

(i) Eye defect

(ii) Correction of Hypermetropia

Discussion

4.	The energy equivalence of 2 g of a substance is -
Answer» The energy equivalence of $2 g$ of a substance is -

Discussion

5.	Statement: Smoking is one of those human weaknesses which tend to test the will power of the smoker to the edge. Conclusions: I. It is very difficult for the smoker to give up smoking even if they want to do so. II. Human beings have other weaknesses as well.
Answer» Statement: Smoking is one of those human weaknesses which tend to test the will power of the smoker to the edge. Conclusions: I. It is very difficult for the smoker to give up smoking even if they want to do so. II. Human beings have other weaknesses as well.

5.

Statement: Smoking is one of those human weaknesses which tend to test the will power of the smoker to the edge. Conclusions: I. It is very difficult for the smoker to give up smoking even if they want to do so. II. Human beings have other weaknesses as well.

Answer»

Statement: Smoking is one of those human weaknesses which tend to test the will power of the smoker to the edge.

Conclusions:
I. It is very difficult for the smoker to give up smoking even if they want to do so.
II. Human beings have other weaknesses as well.

Discussion

6.	Find the time required for 50 Hz sinusoidal alternating current to change its value from zero to rms value.
Answer» Find the time required for $50 Hz$ sinusoidal alternating current to change its value from $z e r o$ to $r m s$ value.

Discussion

7.	Define speed. A ball is thrown up with a speed of 15 ms−1. How high will it go before it begins to fall? (g=9.8 ms−2) [3 MARKS]
Answer» Define speed. A ball is thrown up with a speed of $15 m s^{- 1}$ . How high will it go before it begins to fall? $(g = 9.8 m s^{- 2})$ [3 MARKS]

Discussion

8.	A body is exerting a force of 10 N on a table. The table will exert a force of on the body.
Answer» A body is exerting a force of 10 N on a table. The table will exert a force of on the body.

Discussion

9.	2 infinite wires are kept perpendicular to each other without touching each other explain the nature of the force and also mention the motion of wires
Answer» 2 infinite wires are kept perpendicular to each other without touching each other explain the nature of the force and also mention the motion of wires

Discussion

10.	The illustration shows an object O in front of a plane mirror.Which one of the light rays shown appears to come from the image of O?
Answer» The illustration shows an object O in front of a plane mirror. Which one of the light rays shown appears to come from the image of O?

Discussion

11.	The time period of a satellite orbiting very near to the surface of the earth in a circular path will beapproximately: (Take g 10m/s) (Radius of earth6400 km)(1) 45 minutes(2) 65 minutes(3) 85 minutes(4) 105 minutes
Answer» The time period of a satellite orbiting very near to the surface of the earth in a circular path will be approximately: (Take g 10m/s) (Radius of earth 6400 km) (1) 45 minutes (2) 65 minutes (3) 85 minutes (4) 105 minutes

Discussion

12.	The equivalent resistance between A and B (of the circuit as shown in figure) is
Answer» The equivalent resistance between $A$ and $B$ (of the circuit as shown in figure) is

Discussion

13.	Question 8Choose the incorrect statement:(a) Fleming’s right-hand rule is a simple rule to know the direction of induced current(b) The right-hand thumb rule is used to find the direction of magnetic fields due to current carrying conductors(c) The difference between the direct and alternating currents is that the direct current always flows in one direction, whereas the alternating current reverses its direction periodically(d) In India, the AC changes direction after every 1/ 50 second
Answer» Question 8 Choose the incorrect statement: (a) Fleming’s right-hand rule is a simple rule to know the direction of induced current (b) The right-hand thumb rule is used to find the direction of magnetic fields due to current carrying conductors (c) The difference between the direct and alternating currents is that the direct current always flows in one direction, whereas the alternating current reverses its direction periodically (d) In India, the AC changes direction after every 1/ 50 second

Discussion

14.	How to convert Ethane to Methane?
Answer» How to convert Ethane to Methane?

Discussion

15.	Fig. 9.29 below shows two bulbs with switches and fuse connected to the mains through a three pin socket by means of a three wires cable. Fig. 9.29 (a) Label each component - bulb, switch, fuse and socket. (b) Name and state the colour of insulation of each wire 1, 2 and 3. (c) How are the two bulbs joined : in series or in parallel ?
Answer» Fig. 9.29 below shows two bulbs with switches and fuse connected to the mains through a three pin socket by means of a three wires cable. Fig. 9.29 (a) Label each component - bulb, switch, fuse and socket. (b) Name and state the colour of insulation of each wire 1, 2 and 3. (c) How are the two bulbs joined : in series or in parallel ?

15.

Fig. 9.29 below shows two bulbs with switches and fuse connected to the mains through a three pin socket by means of a three wires cable. Fig. 9.29 (a) Label each component - bulb, switch, fuse and socket. (b) Name and state the colour of insulation of each wire 1, 2 and 3. (c) How are the two bulbs joined : in series or in parallel ?

Answer»

Fig. 9.29 below shows two bulbs with switches and fuse connected to the mains through a three pin socket by means of a three wires cable.

Fig. 9.29

(a) Label each component - bulb, switch, fuse and socket.

(b) Name and state the colour of insulation of each wire 1, 2 and 3.

(c) How are the two bulbs joined : in series or in parallel ?

Discussion

16.	What are the conditions necessary for combustion?
Answer» What are the conditions necessary for combustion?

Discussion

17.	It is said that metals are the good conductor of heat so how in metal bottles water is kept cold for a long duration
Answer» It is said that metals are the good conductor of heat so how in metal bottles water is kept cold for a long duration

Discussion

18.	Draw well labelled ray diagrams for image formation by convex lens when(1) Object is at 2F1(2) Object between F1 and 2F1(3) Object between focus F1 and optical centre O.
Answer» Draw well labelled ray diagrams for image formation by convex lens when (1) Object is at 2F₁ (2) Object between F₁ and 2F₁ (3) Object between focus F₁ and optical centre O.

18.

Draw well labelled ray diagrams for image formation by convex lens when(1) Object is at 2F1(2) Object between F1 and 2F1(3) Object between focus F1 and optical centre O.

Answer»

Draw well labelled ray diagrams for image formation by convex lens when

(1) Object is at 2F₁

(2) Object between F₁ and 2F₁

(3) Object between focus F₁ and optical centre O.

Discussion

19.	Why insulated Cooper wire is used in solenoid mostly. Why not other wire such as steel, aluminium,etc.
Answer» Why insulated Cooper wire is used in solenoid mostly. Why not other wire such as steel, aluminium,etc.

Discussion

20.	during .1sec current in a coil increases from 1A to 1.5A if the induc†an ce of the coil is 60uH induced current in external resis†an ce of 600uohm is 1 1A 2 4/3A 3 2/3A 4 1/2
Answer» during .1sec current in a coil increases from 1A to 1.5A if the induc†an ce of the coil is 60uH induced current in external resis†an ce of 600uohm is 1 1A 2 4/3A 3 2/3A 4 1/2

Discussion

21.	The ratio of angular speed of a second-hand to the hour-hand of a watch is
Answer» The ratio of angular speed of a second-hand to the hour-hand of a watch is

Discussion

22.	10.Why we say conductors have infinite value of dielectric constant. If they have so large value of k why can't we use them in capacitors.
Answer» 10.Why we say conductors have infinite value of dielectric constant. If they have so large value of k why can't we use them in capacitors.

Discussion

23.	Question 2 Redraw the circuit of question 1, putting in an ammeter to measure the current through the resistors and a voltmeter to measure potential difference across the 12Ω resistor. What would be the readings in the ammeter and the voltmeter?
Answer» Question 2 Redraw the circuit of question 1, putting in an ammeter to measure the current through the resistors and a voltmeter to measure potential difference across the $12 Ω$ resistor. What would be the readings in the ammeter and the voltmeter?

Discussion

24.	A convex lens of refractive index 32 has a power of 2.5 D in air. If it is placed in a liquid of refractive index 2, then the new power of the lens is
Answer» A convex lens of refractive index $\frac{3}{2}$ has a power of $2.5 D$ in air. If it is placed in a liquid of refractive index $2$ , then the new power of the lens is

Discussion

25.	A potential barrier of 0.5 V exists across a p-n junction (i) If the depletion region is 5 x 10^7m wide. What is the average intensity of the electric field in this region ? (ii) An electron with speed 5 x 10^{5 } m/s approachesthe p-n junction from the n-side with what speed will it enter the p-side?
Answer» A potential barrier of 0.5 V exists across a p-n junction (i) If the depletion region is 5 x 10^7m wide. What is the average intensity of the electric field in this region ? (ii) An electron with speed 5 x 10^{5 } m/s approachesthe p-n junction from the n-side with what speed will it enter the p-side?

Discussion

26.	11. An equi convex glass lens (i) has focal length f and power P. If is cut into two symmetrical halves (i)by a plane containing the principal axis. The two pieces are recombined as shown in fig. The powerof new combination is(3) 2P4) Zero
Answer» 11. An equi convex glass lens (i) has focal length f and power P. If is cut into two symmetrical halves (i) by a plane containing the principal axis. The two pieces are recombined as shown in fig. The power of new combination is (3) 2P 4) Zero

Discussion

27.	Question 10The given graph shows the displacement versus time relation for a disturbance travelling with velocity of 1500 ms−1 . Calculate the wavelength of the disturbance
Answer» Question 10 The given graph shows the displacement versus time relation for a disturbance travelling with velocity of $1500 m s^{- 1}$ . Calculate the wavelength of the disturbance

Discussion

28.	Why the magnetic field is non conservative field but electric field conservative
Answer» Why the magnetic field is non conservative field but electric field conservative

Discussion

29.	A person needs a lens of power –4.5 D for correction of her vision. What kind of defect in vision is she suffering from?
Answer» A person needs a lens of power –4.5 D for correction of her vision. What kind of defect in vision is she suffering from?

Discussion

30.	A biogas plant produces methane and supplies to the families . If a family requires 15000 kJ of energy per day, how many days will the quota of 10 kg will last ?( enthalpy of combustion of methane = -1665 kJ /mol)
Answer» A biogas plant produces methane and supplies to the families . If a family requires 15000 kJ of energy per day, how many days will the quota of 10 kg will last ?( enthalpy of combustion of methane = -1665 kJ /mol)

Discussion

31.	Question 8What is the acceleration of free fall?
Answer» Question 8 What is the acceleration of free fall?

Discussion

32.	Give some examples of secondary cells.
Answer» Give some examples of secondary cells.

Discussion

33.	Radius of a non-conducting sphere is R and volume charge density is ρ. Electric field at a distance r (r<R) will follow
Answer» Radius of a non-conducting sphere is $R$ and volume charge density is $ρ$ . Electric field at a distance $r (r < R)$ will follow

Discussion

34.	A mixture of ideal gas containing 5 moles of monatomic gas and 1 mole of rigid diatomic gas is initially at pressure P0, volume V0 and temperature T0. If the gas mixture is adiabatically compressed to a volume V0/4, then the correct statement(s) is/are,(Given 21.2=2.3;23.2=9.2;R is gas constant)
Answer» A mixture of ideal gas containing 5 moles of monatomic gas and 1 mole of rigid diatomic gas is initially at pressure $P_{0}$ , volume $V_{0}$ and temperature $T_{0}$ . If the gas mixture is adiabatically compressed to a volume $V_{0} / 4$ , then the correct statement(s) is/are, (Given $2^{1.2} = 2.3; 2^{3.2} = 9.2; R$ is gas constant)

Discussion

35.	A uniform metre scale is kept in equilibrium. It is supported at the 60 cm mark and a mass M is suspended from the 90 cm mark as shown in the figure. What is the relation between the weight of the scale and the weight of mass M?
Answer» A uniform metre scale is kept in equilibrium. It is supported at the 60 cm mark and a mass M is suspended from the 90 cm mark as shown in the figure. What is the relation between the weight of the scale and the weight of mass M?

Discussion

36.	in formulae magnetic force= [qvb]is this velocity is wrt observer on ground oe this is relative velocitywhat velocity mean in electromagnetism
Answer» in formulae magnetic force= [qvb] is this velocity is wrt observer on ground oe this is relative velocity what velocity mean in electromagnetism

Discussion

37.	A transformer has 200 turns in primary coil and 600 turns in secondary coil. If a 220 V DC is applied across the primary coil, what will be the voltage across the secondary coil.
Answer» A transformer has $200$ turns in primary coil and $600$ turns in secondary coil. If a $220 V$ $D C$ is applied across the primary coil, what will be the voltage across the secondary coil.

Discussion

38.	Can I get all numericals from the light chapter
Answer» Can I get all numericals from the light chapter

Discussion

39.	Why nuclear energy can not be used directly to cook food?
Answer» Why nuclear energy can not be used directly to cook food?

Discussion

40.	The values of two resistors are (5.0+-0.2)k ohm and (10.0+-0.1)k ohm. What is the percentage error in the equivalent resistance when they are connected in parallel? 1) 2% 2) 5% 3) 7% 4) 10%
Answer» The values of two resistors are (5.0+-0.2)k ohm and (10.0+-0.1)k ohm. What is the percentage error in the equivalent resistance when they are connected in parallel? 1) 2% 2) 5% 3) 7% 4) 10%

40.

The values of two resistors are (5.0+-0.2)k ohm and (10.0+-0.1)k ohm. What is the percentage error in the equivalent resistance when they are connected in parallel? 1) 2% 2) 5% 3) 7% 4) 10%

Answer»

The values of two resistors are (5.0+-0.2)k ohm and (10.0+-0.1)k ohm. What is the percentage error in the equivalent resistance when they are connected in parallel?

1) 2%

2) 5%

3) 7%

4) 10%

Discussion

41.	A thin flexible wire of length L is connected to two adjacent fixed points and carries a current I in the clockwise direction as shown in figure. When the system is put in a uniform magnetic field of strength B, going into plane of paper, the tension developed in the wire will be:
Answer» A thin flexible wire of length $L$ is connected to two adjacent fixed points and carries a current $I$ in the clockwise direction as shown in figure. When the system is put in a uniform magnetic field of strength $B$ , going into plane of paper, the tension developed in the wire will be:

Discussion

42.	prove that [2 pie r=n lambda] the circumference of the bohr orbit for the hydrogen atom is an integral multiple of the de brogli wavelength
Answer» prove that [2 pie r=n lambda] the circumference of the bohr orbit for the hydrogen atom is an integral multiple of the de brogli wavelength

Discussion

43.	A spherical mirror and a spherical lens each have a focal length of, -15 cm. The mirror and the lens are likely to be : (a) both concave. (b) both convex. (c) the mirror is concave but the lens is convex. (d) the mirror is convex but the lens is concave.
Answer» A spherical mirror and a spherical lens each have a focal length of, -15 cm. The mirror and the lens are likely to be : (a) both concave. (b) both convex. (c) the mirror is concave but the lens is convex. (d) the mirror is convex but the lens is concave.

Discussion

44.	In a Xerox machine, the black ink's toner particles are negatively charged. They strongly stick to the white A4 sheet paper and form letters and images. What charge should the A4 sheet possess for this process to take place?
Answer» In a Xerox machine, the black ink's toner particles are negatively charged. They strongly stick to the white A4 sheet paper and form letters and images. What charge should the A4 sheet possess for this process to take place?

Discussion

45.	A NPN transistor conducts when
Answer» A NPN transistor conducts when

Discussion

46.	If a thin aluminium sheet is introduced between a capacitor. what will be the change in capacitance
Answer» If a thin aluminium sheet is introduced between a capacitor. what will be the change in capacitance

Discussion

47.	A 6 kg mass moving with a velocity of 20 ms−1 collides with another 2 kg mass moving in opposite direction with a velocity of 10 ms−1. The momentum of system is.
Answer» A $6 k g$ mass moving with a velocity of $20 m s^{- 1}$ collides with another $2 k g$ mass moving in opposite direction with a velocity of $10 m s^{- 1}$ . The momentum of system is.

Discussion

48.	Two identical small plastic balls are rubbed against a piece of wool such that both of them recevied approximately 2×10^{12}and 2.5×10^{12} electrons respectively.Now both the charged balls are kept at a dis†an ce of 25 cm in air. Calculate the nature and magnitude of the force between both the balls.If charges on the both balls are increased by 10 percent then calculate the change in electrosatic force between two balls.
Answer» Two identical small plastic balls are rubbed against a piece of wool such that both of them recevied approximately 2×10^{12}and 2.5×10^{12} electrons respectively.Now both the charged balls are kept at a dis†an ce of 25 cm in air. Calculate the nature and magnitude of the force between both the balls.If charges on the both balls are increased by 10 percent then calculate the change in electrosatic force between two balls.

Discussion

49.	What's the S.I unit of mass??
Answer» What's the S.I unit of mass??

Discussion

50.	If one wants to remove all the mass of the earth to infinity in order to break it up completely. The amount of energy that needs to be supplied will be x5GM2Rwhere x is (Round off to the Nearest Integer)(M is the mass of earth, R is the radius of earth, G is the gravitational constant)
Answer» If one wants to remove all the mass of the earth to infinity in order to break it up completely. The amount of energy that needs to be supplied will be $\frac{x}{5} \frac{G M^{2}}{R}$ where $x$ is (Round off to the Nearest Integer) ( $M$ is the mass of earth, $R$ is the radius of earth, $G$ is the gravitational constant)

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

A wire of length 0.24 m and diameter 3.0×10−5 m has a resistance of 160Ω. Calculate the resistivity of the material.?

What is furnace?

What is hypermetropia? State the two causes. With the help of labelled ray diagram, show (i) Eye defect (ii) Correction of Hypermetropia

The energy equivalence of 2 g of a substance is -

Statement: Smoking is one of those human weaknesses which tend to test the will power of the smoker to the edge. Conclusions: I. It is very difficult for the smoker to give up smoking even if they want to do so. II. Human beings have other weaknesses as well.

Find the time required for 50 Hz sinusoidal alternating current to change its value from zero to rms value.

Define speed. A ball is thrown up with a speed of 15 ms−1. How high will it go before it begins to fall? (g=9.8 ms−2) [3 MARKS]

A body is exerting a force of 10 N on a table. The table will exert a force of on the body.

2 infinite wires are kept perpendicular to each other without touching each other explain the nature of the force and also mention the motion of wires

The illustration shows an object O in front of a plane mirror.Which one of the light rays shown appears to come from the image of O?

The time period of a satellite orbiting very near to the surface of the earth in a circular path will beapproximately: (Take g 10m/s) (Radius of earth6400 km)(1) 45 minutes(2) 65 minutes(3) 85 minutes(4) 105 minutes

The equivalent resistance between A and B (of the circuit as shown in figure) is

How to convert Ethane to Methane?

What are the conditions necessary for combustion?

It is said that metals are the good conductor of heat so how in metal bottles water is kept cold for a long duration

Draw well labelled ray diagrams for image formation by convex lens when(1) Object is at 2F1(2) Object between F1 and 2F1(3) Object between focus F1 and optical centre O.

Why insulated Cooper wire is used in solenoid mostly. Why not other wire such as steel, aluminium,etc.

during .1sec current in a coil increases from 1A to 1.5A if the induc†an ce of the coil is 60uH induced current in external resis†an ce of 600uohm is 1 1A 2 4/3A 3 2/3A 4 1/2

The ratio of angular speed of a second-hand to the hour-hand of a watch is

10.Why we say conductors have infinite value of dielectric constant. If they have so large value of k why can't we use them in capacitors.

Question 2 Redraw the circuit of question 1, putting in an ammeter to measure the current through the resistors and a voltmeter to measure potential difference across the 12Ω resistor. What would be the readings in the ammeter and the voltmeter?

A convex lens of refractive index 32 has a power of 2.5 D in air. If it is placed in a liquid of refractive index 2, then the new power of the lens is

11. An equi convex glass lens (i) has focal length f and power P. If is cut into two symmetrical halves (i)by a plane containing the principal axis. The two pieces are recombined as shown in fig. The powerof new combination is(3) 2P4) Zero

Question 10The given graph shows the displacement versus time relation for a disturbance travelling with velocity of 1500 ms−1 . Calculate the wavelength of the disturbance

Why the magnetic field is non conservative field but electric field conservative

A person needs a lens of power –4.5 D for correction of her vision. What kind of defect in vision is she suffering from?

A biogas plant produces methane and supplies to the families . If a family requires 15000 kJ of energy per day, how many days will the quota of 10 kg will last ?( enthalpy of combustion of methane = -1665 kJ /mol)

Question 8What is the acceleration of free fall?

Give some examples of secondary cells.

Radius of a non-conducting sphere is R and volume charge density is ρ. Electric field at a distance r (r&lt;R) will follow

A mixture of ideal gas containing 5 moles of monatomic gas and 1 mole of rigid diatomic gas is initially at pressure P0, volume V0 and temperature T0. If the gas mixture is adiabatically compressed to a volume V0/4, then the correct statement(s) is/are,(Given 21.2=2.3;23.2=9.2;R is gas constant)

A uniform metre scale is kept in equilibrium. It is supported at the 60 cm mark and a mass M is suspended from the 90 cm mark as shown in the figure. What is the relation between the weight of the scale and the weight of mass M?

in formulae magnetic force= [qvb]is this velocity is wrt observer on ground oe this is relative velocitywhat velocity mean in electromagnetism

A transformer has 200 turns in primary coil and 600 turns in secondary coil. If a 220 V DC is applied across the primary coil, what will be the voltage across the secondary coil.

Can I get all numericals from the light chapter

Why nuclear energy can not be used directly to cook food?

The values of two resistors are (5.0+-0.2)k ohm and (10.0+-0.1)k ohm. What is the percentage error in the equivalent resistance when they are connected in parallel? 1) 2% 2) 5% 3) 7% 4) 10%

A thin flexible wire of length L is connected to two adjacent fixed points and carries a current I in the clockwise direction as shown in figure. When the system is put in a uniform magnetic field of strength B, going into plane of paper, the tension developed in the wire will be:

prove that [2 pie r=n lambda] the circumference of the bohr orbit for the hydrogen atom is an integral multiple of the de brogli wavelength

A spherical mirror and a spherical lens each have a focal length of, -15 cm. The mirror and the lens are likely to be : (a) both concave. (b) both convex. (c) the mirror is concave but the lens is convex. (d) the mirror is convex but the lens is concave.

In a Xerox machine, the black ink's toner particles are negatively charged. They strongly stick to the white A4 sheet paper and form letters and images. What charge should the A4 sheet possess for this process to take place?

A NPN transistor conducts when

If a thin aluminium sheet is introduced between a capacitor. what will be the change in capacitance

A 6 kg mass moving with a velocity of 20 ms−1 collides with another 2 kg mass moving in opposite direction with a velocity of 10 ms−1. The momentum of system is.

What's the S.I unit of mass??

If one wants to remove all the mass of the earth to infinity in order to break it up completely. The amount of energy that needs to be supplied will be x5GM2Rwhere x is (Round off to the Nearest Integer)(M is the mass of earth, R is the radius of earth, G is the gravitational constant)

Radius of a non-conducting sphere is R and volume charge density is ρ. Electric field at a distance r (r<R) will follow