50278 + Interview Questions in Physics

1.	A particle of mass m and carrying charge -q1 is moving around a charge+q2 along a circular path of radius r. Find period of revolution of the charge q
Answer» A particle of mass m and carrying charge -q1 is moving around a charge+q2 along a circular path of radius r. Find period of revolution of the charge q

Discussion

2.	Light is an electromagnetic wave. Its speed in vacuum is given by the expression
Answer» Light is an electromagnetic wave. Its speed in vacuum is given by the expression

Discussion

3.	A capacitor of capacitance 100 μF is connected to a battery of 10 V for a long time and then disconnected from it. It is now connected across a solenoid having 200 turns per meter. It is found that the potential difference across the capacitor drops to 90% of its maximum value in 2 s. Find the average magnetic field induced at the centre of the solenoid ?
Answer» A capacitor of capacitance $100 μ F$ is connected to a battery of $10 V$ for a long time and then disconnected from it. It is now connected across a solenoid having $200$ turns per meter. It is found that the potential difference across the capacitor drops to $90 %$ of its maximum value in $2 s .$ Find the average magnetic field induced at the centre of the solenoid ?

Discussion

4.	Dimensional formula of resolving power of telescope and resolving power of microscope respectively are
Answer» Dimensional formula of resolving power of telescope and resolving power of microscope respectively are

Discussion

5.	In the Pressure versus Volume graph shown, in the process of going from a to b, 60 J of heat is added, and in the process of going from b to d, 20 J of heat is added. In the process of going from a to c to d, what is the total heat added?
Answer» In the Pressure versus Volume graph shown, in the process of going from $a$ to $b,$ $60 J$ of heat is added, and in the process of going from $b$ to $d,$ $20 J$ of heat is added. In the process of going from $a$ to $c$ to $d$ , what is the total heat added?

Discussion

6.	In figure, distance(d) between conductors carrying currents I1 and I2 is varied. Which of the following graphs correctly represents the variation of force(F) between the conductors with distance(d)?
Answer» In figure, distance $(d)$ between conductors carrying currents $I_{1}$ and $I_{2}$ is varied. Which of the following graphs correctly represents the variation of force $(F)$ between the conductors with distance $(d)$ ?

Discussion

7.	a mild steel wire of length 2L cross section area is fixed for sondoli between two pillars a small mass M is suspended from the point of the wire if extension in wire are within elastic limit than the discretion of the midpoint of the
Answer» a mild steel wire of length 2L cross section area is fixed for sondoli between two pillars a small mass M is suspended from the point of the wire if extension in wire are within elastic limit than the discretion of the midpoint of the

Discussion

8.	One mole of an ideal gas with CpCv=γ at absolute temperature T1 is adiabatically compressed from an initial pressure P1 to a final pressure P2. The resulting temperature T2 of the gas is given by
Answer» One mole of an ideal gas with $\frac{C_{p}}{C_{v}} = γ$ at absolute temperature $T_{1}$ is adiabatically compressed from an initial pressure $P_{1}$ to a final pressure $P_{2}$ . The resulting temperature $T_{2}$ of the gas is given by

Discussion

9.	Why are charges independent of mass
Answer» Why are charges independent of mass

Discussion

10.	A stone projected with a velocity u at an angle θ with the horizontal reaches maximum height H1. When it is projected with velocity u at an angle (π2−θ) with the horizontal, it reaches maximum height H2. The relation between the horizontal range R of the projectile, H1 and H2 is
Answer» A stone projected with a velocity u at an angle $θ$ with the horizontal reaches maximum height $H_{1}$ . When it is projected with velocity u at an angle $(\frac{π}{2} - θ)$ with the horizontal, it reaches maximum height $H_{2}$ . The relation between the horizontal range R of the projectile, $H_{1}$ and $H_{2}$ is

Discussion

11.	a projectile is thrown with an initial velocity of v=ai^ +bj^. if the range of the projectile is double the maximum height attained by then it ;1)a=2b 2)a=b 3)b=2a 4)4a=b
Answer» a projectile is thrown with an initial velocity of v=ai^ +bj^. if the range of the projectile is double the maximum height attained by then it ; 1)a=2b 2)a=b 3)b=2a 4)4a=b

Discussion

12.	The direction of induced e.m.f. during electromagnetic induction is given by
Answer» The direction of induced e.m.f. during electromagnetic induction is given by

Discussion

13.	The valence of an impurity added to germanium crystal in order to convert it into a P-type semi conductor is ?
Answer» The valence of an impurity added to germanium crystal in order to convert it into a P-type semi conductor is ?

Discussion

14.	A solid ball of density half that of water falls freely under gravity from a height of 19.6 m and then enters a stream of water. Upto what depth will the ball go? [Take g=9.8 m/s2]
Answer» A solid ball of density half that of water falls freely under gravity from a height of $19.6 m$ and then enters a stream of water. Upto what depth will the ball go? [Take $g = 9.8 {m/s}^{2}]$

Discussion

15.	A wire of length L and 3 identical resistors of the same resistance as the wire are connected in series. Due to the current, the temperature of the wire is raised by ΔT in time t. N number of similar resistors are now connected in series with a wire of the same material and cross section, but of length 2L. The temperature of the wire is raised by the same amount ΔT in the same time t. The value of N is
Answer» A wire of length $L$ and 3 identical resistors of the same resistance as the wire are connected in series. Due to the current, the temperature of the wire is raised by $Δ T$ in time $t$ . $N$ number of similar resistors are now connected in series with a wire of the same material and cross section, but of length $2 L$ . The temperature of the wire is raised by the same amount $Δ T$ in the same time $t$ . The value of $N$ is

Discussion

16.	A 60 μF capacitor is connected to a 110 V, 60 Hz ac supply. Determine the rms value of the current in the circuit.
Answer» A 60 μF capacitor is connected to a 110 V, 60 Hz ac supply. Determine the rms value of the current in the circuit.

Discussion

17.	If x=asin(ωt+π6) and x=acoswt then what is the phase difference between the two waves?
Answer» If $x = a s i n (ω t + \frac{π}{6})$ and $x = acoswt$ then what is the phase difference between the two waves?

Discussion

18.	You are given the two circuits as shown in Fig. 14.44. Show thatcircuit (a) acts as OR gate while the circuit (b) acts as AND gate.
Answer» You are given the two circuits as shown in Fig. 14.44. Show thatcircuit (a) acts as OR gate while the circuit (b) acts as AND gate.

Discussion

19.	An equilateral triangle has mass &quotm" on all its vertices, what is the force acting on the centroid of mass &quot2m"?
Answer» An equilateral triangle has mass "m" on all its vertices, what is the force acting on the centroid of mass "2m"?

Discussion

20.	RAYS FROM THE SUN ARE FOCUSSED BY A LENS OF DIAMETER 5 cm ON A BLOCK OF ICE AND 10 g OF ICE IS MELTED N 20 MIN . FIND THE HEAT FROM THE SUN REACHING THE EARTH PER MIN PER SQUARE cm ?
Answer» RAYS FROM THE SUN ARE FOCUSSED BY A LENS OF DIAMETER 5 cm ON A BLOCK OF ICE AND 10 g OF ICE IS MELTED N 20 MIN . FIND THE HEAT FROM THE SUN REACHING THE EARTH PER MIN PER SQUARE cm ?

Discussion

21.	A block is kept on the floor of an elevator at rest. The elevator starts descending with an acceleration 12m/s2. find the displacement of the block during the first 0.2 s after the start. Take g=10m/s2
Answer» A block is kept on the floor of an elevator at rest. The elevator starts descending with an acceleration $12 m / s^{2}$ . find the displacement of the block during the first 0.2 s after the start. Take $g = 10 m / s^{2}$

Discussion

22.	7. The volume of a gas measured at 27^° C and 1 atm pressure is 10 L. To reduce the volume to 2 L at 1 atm pressure, the temperature required is (a) 60 K (b) 75 K (c) 150 K d) 225 K
Answer» 7. The volume of a gas measured at 27^° C and 1 atm pressure is 10 L. To reduce the volume to 2 L at 1 atm pressure, the temperature required is (a) 60 K (b) 75 K (c) 150 K d) 225 K

Discussion

23.	57.Graph between unit and no.
Answer» 57.Graph between unit and no.

Discussion

24.	define ionisation enthalpy
Answer» define ionisation enthalpy

Discussion

25.	Find tan(-910°)
Answer» Find tan(-910°)

Discussion

26.	If the distance between sun and earth is increased by 2%,then find the % change in gravitational force acting between them.
Answer» If the distance between sun and earth is increased by 2%,then find the % change in gravitational force acting between them.

Discussion

27.	a 10 metric ton truck drives up a hilly road of gradient 1 in 50 at a speed of 36 km/h if the coefficient of kinetic friction between the road and tyres is 0.2 find the power delivered by the engine
Answer» a 10 metric ton truck drives up a hilly road of gradient 1 in 50 at a speed of 36 km/h if the coefficient of kinetic friction between the road and tyres is 0.2 find the power delivered by the engine

Discussion

28.	The equivalent resistance across points A and B is :
Answer» The equivalent resistance across points $A$ and $B$ is :

Discussion

29.	A ball is thrown downward with some velocity into a viscous liquid. Draw graph that represents correct variation of velocity with time
Answer» A ball is thrown downward with some velocity into a viscous liquid. Draw graph that represents correct variation of velocity with time

Discussion

30.	One morning an old man walked bare-foot to replace the fuse wire fitted with power supply mains of his house. Suddenly he screamed and collapsed on the floor. His wife cried loudly for help. His neighbour's son Anil heard the cries and rushed to the place with shoes on. He took a wooden baton and used it to switch off the main supply. Answer the following questions: (i) What is the voltage and frequency of mains supply in India ? (ii) These days most of the electrical devices we use a.c. voltage. Why? (iii) Can a transformer be used to step up d.c. voltage? (iv) Write two qualities displayed by Anil through his actions.
Answer» One morning an old man walked bare-foot to replace the fuse wire fitted with power supply mains of his house. Suddenly he screamed and collapsed on the floor. His wife cried loudly for help. His neighbour's son Anil heard the cries and rushed to the place with shoes on. He took a wooden baton and used it to switch off the main supply. Answer the following questions: (i) What is the voltage and frequency of mains supply in India ? (ii) These days most of the electrical devices we use a.c. voltage. Why? (iii) Can a transformer be used to step up d.c. voltage? (iv) Write two qualities displayed by Anil through his actions.

Discussion

31.	A fluid while flowing through a tube as shown passes through points A and B. Find the velocity of the fluid at point B.
Answer» A fluid while flowing through a tube as shown passes through points A and B. Find the velocity of the fluid at point B.

Discussion

32.	a golf ball is projected at an angle of 30 with the horizontal at a speed of 10 m/s . the angle made by line joining point of projection with the point of max height ?
Answer» a golf ball is projected at an angle of 30 with the horizontal at a speed of 10 m/s . the angle made by line joining point of projection with the point of max height ?

Discussion

33.	Arjun facing North says that he felt like all the buildings were moving ahead of him while he was in a vehicle. Is Arjun's vehicle stationary? Give reason for your answer.
Answer» Arjun facing North says that he felt like all the buildings were moving ahead of him while he was in a vehicle. Is Arjun's vehicle stationary? Give reason for your answer.

Discussion

34.	Two identical thin uniform rods of each mass m and length l are joined to form L shape. Find the moment of inertia of this system about an axis passing through the point at which both rods are joined and perpendicular to their lengths.
Answer» Two identical thin uniform rods of each mass $m$ and length $l$ are joined to form $L$ shape. Find the moment of inertia of this system about an axis passing through the point at which both rods are joined and perpendicular to their lengths.

Discussion

35.	A monochromatic beam of light is incident at 60∘ on one face of an equilateral prism of refractive index n and emerges from the opposite face making an angle θ with the normal. For n=√3, the value of θ is 60∘ and dθdn=m. The value of m is.
Answer» A monochromatic beam of light is incident at $60^{\circ}$ on one face of an equilateral prism of refractive index $n$ and emerges from the opposite face making an angle $θ$ with the normal. For $n = \sqrt{3},$ the value of $θ$ is $60^{\circ}$ and $\frac{d θ}{d n} = m .$ The value of $m$ is.

Discussion

36.	A shell of mass 200 gm is ejected from a gun ofmass 4 kg by an explosion that generates 1.06of energy. The initial velocity of the shell is\lbrack AIPMT (Prelims)-2008)(1) 120 ms(2) 100 ms-(3) 80 ms(4) 40 mst
Answer» A shell of mass 200 gm is ejected from a gun ofmass 4 kg by an explosion that generates 1.06of energy. The initial velocity of the shell is\lbrack AIPMT (Prelims)-2008)(1) 120 ms(2) 100 ms-(3) 80 ms(4) 40 mst

Discussion

37.	A man running on horizontal Road at 8 km per hour finds rain falling vertically. He increases speed to 12 km per hour and find that the Drop makes angle 30 degree with the particle find the speed and direction of rain with respect to the road
Answer» A man running on horizontal Road at 8 km per hour finds rain falling vertically. He increases speed to 12 km per hour and find that the Drop makes angle 30 degree with the particle find the speed and direction of rain with respect to the road

Discussion

38.	12 wires each having resistance r are joined to form a cube as shown.find the equivalent resistance between the ends of a face diagonal such as A and C.find the equivalent resistance between ends of an edge such as A and B and also along body diagonal A amd F
Answer» 12 wires each having resistance r are joined to form a cube as shown.find the equivalent resistance between the ends of a face diagonal such as A and C.find the equivalent resistance between ends of an edge such as A and B and also along body diagonal A amd F

Discussion

39.	charge +Q and radius R what will be value ofelectric flux paasing through a imaginaryconcentric sphere of radius R/2 :-(1) 26,(2)280 (2)4ε ο8E0 (4) Zero0
Answer» charge +Q and radius R what will be value of electric flux paasing through a imaginary concentric sphere of radius R/2 :- (1) 26, (2) 280 (2) 4ε ο 8E0 (4) Zero 0

Discussion

40.	The momentum p of particle is varying with time t as p=2+3t^2.The force acting on the particle at t=3s will be
Answer» The momentum p of particle is varying with time t as p=2+3t^2.The force acting on the particle at t=3s will be

Discussion

41.	Question 2A student sitting on the last bench can read the letters written on the blackboard but is not able to read the letters written in his textbook. Which of the following statements is correct?(a) The near point of his eyes has receded away(b) The near point of his eyes has come closer to him(c) The far point of his eyes has come closer to him(d) The far point of his eyes has receded away
Answer» Question 2 A student sitting on the last bench can read the letters written on the blackboard but is not able to read the letters written in his textbook. Which of the following statements is correct? (a) The near point of his eyes has receded away (b) The near point of his eyes has come closer to him (c) The far point of his eyes has come closer to him (d) The far point of his eyes has receded away

Discussion

42.	Define and drive the expression for electric susceptibility
Answer» Define and drive the expression for electric susceptibility

Discussion

43.	Consider the diode circuit shown in the figure below:The input output characteristic curve of the circuit can be represented as(Assume cut-in voltage of diode D1 and D2 is equal to 0.7 V)
Answer» Consider the diode circuit shown in the figure below: The input output characteristic curve of the circuit can be represented as (Assume cut-in voltage of diode $D_{1}$ and $D_{2}$ is equal to 0.7 V)

Discussion

44.	17.Explain the following statement- 'For electrostatic field, the closed integral of electric field w.r.t displacement is always 0, because electric force F = qE on a point charge is conservative.
Answer» 17.Explain the following statement- 'For electrostatic field, the closed integral of electric field w.r.t displacement is always 0, because electric force F = qE on a point charge is conservative.

Discussion

45.	A person is standing on a truck moving with a constant velocity of 14.7 m/s on a horizontal road. The man throws a ball in such a way that it returns to the truck after the truck has moved 58.8 m. Find the speed and the angle of projection (a) As seen from the truck, (b) Aa seen from the road.
Answer» A person is standing on a truck moving with a constant velocity of 14.7 m/s on a horizontal road. The man throws a ball in such a way that it returns to the truck after the truck has moved 58.8 m. Find the speed and the angle of projection (a) As seen from the truck, (b) Aa seen from the road.

45.

A person is standing on a truck moving with a constant velocity of 14.7 m/s on a horizontal road. The man throws a ball in such a way that it returns to the truck after the truck has moved 58.8 m. Find the speed and the angle of projection (a) As seen from the truck, (b) Aa seen from the road.

Answer»

A person is standing on a truck moving with a constant velocity of 14.7 m/s on a horizontal road. The man throws a ball in such a way that it returns to the truck after the truck has moved 58.8 m. Find the speed and the angle of projection

(a) As seen from the truck,

(b) Aa seen from the road.

Discussion

46.	A sphere rolls without slipping on an inclined plane of inclination . Then the minimum value of coefficient of friction so that the sphere rolls with out slipping is
Answer» A sphere rolls without slipping on an inclined plane of inclination $\theta$ . Then the minimum value of coefficient of friction so that the sphere rolls with out slipping is

Discussion

47.	A cylinder of radius r and of thermal conductivity k1 is surrounded by a cylindrical shell of inner radius r and outer radius 2r made of a material of thermal conductivity k2. The effective thermal conductivity of the system is
Answer» A cylinder of radius r and of thermal conductivity $k_{1}$ is surrounded by a cylindrical shell of inner radius r and outer radius 2r made of a material of thermal conductivity $k_{2}$ . The effective thermal conductivity of the system is

Discussion

48.	What is meant by refraction
Answer» What is meant by refraction

Discussion

49.	A block placed on an inclined plane of slope angle θ slides down with a constant speed. The coefficient of kinetic friction is equal to (correct answer + 1, wrong answer - 0.25)
Answer» A block placed on an inclined plane of slope angle $θ$ slides down with a constant speed. The coefficient of kinetic friction is equal to (correct answer + 1, wrong answer - 0.25)

Discussion

50.	A squirrel of mass m climbs slowly on a thin straight vertical rod of length 8 m. Mass of rod is negligible. Due to the weight of squirrel, the rod rotates and a restoring torque cθ is developed. If c = 2 mgL, then maximum length that squirrel can climb on rod without touching ground is (Write upto two digits after the decimal point.)
Answer» A squirrel of mass m climbs slowly on a thin straight vertical rod of length 8 m. Mass of rod is negligible. Due to the weight of squirrel, the rod rotates and a restoring torque $c θ$ is developed. If c = 2 mgL, then maximum length that squirrel can climb on rod without touching ground is (Write upto two digits after the decimal point.)

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

A particle of mass m and carrying charge -q1 is moving around a charge+q2 along a circular path of radius r. Find period of revolution of the charge q

Light is an electromagnetic wave. Its speed in vacuum is given by the expression

Dimensional formula of resolving power of telescope and resolving power of microscope respectively are

In the Pressure versus Volume graph shown, in the process of going from a to b, 60 J of heat is added, and in the process of going from b to d, 20 J of heat is added. In the process of going from a to c to d, what is the total heat added?

In figure, distance(d) between conductors carrying currents I1 and I2 is varied. Which of the following graphs correctly represents the variation of force(F) between the conductors with distance(d)?

a mild steel wire of length 2L cross section area is fixed for sondoli between two pillars a small mass M is suspended from the point of the wire if extension in wire are within elastic limit than the discretion of the midpoint of the

One mole of an ideal gas with CpCv=γ at absolute temperature T1 is adiabatically compressed from an initial pressure P1 to a final pressure P2. The resulting temperature T2 of the gas is given by

Why are charges independent of mass

A stone projected with a velocity u at an angle θ with the horizontal reaches maximum height H1. When it is projected with velocity u at an angle (π2−θ) with the horizontal, it reaches maximum height H2. The relation between the horizontal range R of the projectile, H1 and H2 is

a projectile is thrown with an initial velocity of v=ai^ +bj^. if the range of the projectile is double the maximum height attained by then it ;1)a=2b 2)a=b 3)b=2a 4)4a=b

The direction of induced e.m.f. during electromagnetic induction is given by

The valence of an impurity added to germanium crystal in order to convert it into a P-type semi conductor is ?

A solid ball of density half that of water falls freely under gravity from a height of 19.6 m and then enters a stream of water. Upto what depth will the ball go? [Take g=9.8 m/s2]

A 60 μF capacitor is connected to a 110 V, 60 Hz ac supply. Determine the rms value of the current in the circuit.

If x=asin(ωt+π6) and x=acoswt then what is the phase difference between the two waves?

You are given the two circuits as shown in Fig. 14.44. Show thatcircuit (a) acts as OR gate while the circuit (b) acts as AND gate.

An equilateral triangle has mass &quotm" on all its vertices, what is the force acting on the centroid of mass &quot2m"?

RAYS FROM THE SUN ARE FOCUSSED BY A LENS OF DIAMETER 5 cm ON A BLOCK OF ICE AND 10 g OF ICE IS MELTED N 20 MIN . FIND THE HEAT FROM THE SUN REACHING THE EARTH PER MIN PER SQUARE cm ?

A block is kept on the floor of an elevator at rest. The elevator starts descending with an acceleration 12m/s2. find the displacement of the block during the first 0.2 s after the start. Take g=10m/s2

7. The volume of a gas measured at 27^° C and 1 atm pressure is 10 L. To reduce the volume to 2 L at 1 atm pressure, the temperature required is (a) 60 K (b) 75 K (c) 150 K d) 225 K

57.Graph between unit and no.

define ionisation enthalpy

Find tan(-910°)

If the distance between sun and earth is increased by 2%,then find the % change in gravitational force acting between them.

a 10 metric ton truck drives up a hilly road of gradient 1 in 50 at a speed of 36 km/h if the coefficient of kinetic friction between the road and tyres is 0.2 find the power delivered by the engine

The equivalent resistance across points A and B is :

A ball is thrown downward with some velocity into a viscous liquid. Draw graph that represents correct variation of velocity with time

A fluid while flowing through a tube as shown passes through points A and B. Find the velocity of the fluid at point B.

a golf ball is projected at an angle of 30 with the horizontal at a speed of 10 m/s . the angle made by line joining point of projection with the point of max height ?

Arjun facing North says that he felt like all the buildings were moving ahead of him while he was in a vehicle. Is Arjun's vehicle stationary? Give reason for your answer.

Two identical thin uniform rods of each mass m and length l are joined to form L shape. Find the moment of inertia of this system about an axis passing through the point at which both rods are joined and perpendicular to their lengths.

A monochromatic beam of light is incident at 60∘ on one face of an equilateral prism of refractive index n and emerges from the opposite face making an angle θ with the normal. For n=√3, the value of θ is 60∘ and dθdn=m. The value of m is.

A shell of mass 200 gm is ejected from a gun ofmass 4 kg by an explosion that generates 1.06of energy. The initial velocity of the shell is\lbrack AIPMT (Prelims)-2008)(1) 120 ms(2) 100 ms-(3) 80 ms(4) 40 mst

A man running on horizontal Road at 8 km per hour finds rain falling vertically. He increases speed to 12 km per hour and find that the Drop makes angle 30 degree with the particle find the speed and direction of rain with respect to the road

12 wires each having resistance r are joined to form a cube as shown.find the equivalent resistance between the ends of a face diagonal such as A and C.find the equivalent resistance between ends of an edge such as A and B and also along body diagonal A amd F

charge +Q and radius R what will be value ofelectric flux paasing through a imaginaryconcentric sphere of radius R/2 :-(1) 26,(2)280 (2)4ε ο8E0 (4) Zero0

The momentum p of particle is varying with time t as p=2+3t^2.The force acting on the particle at t=3s will be

Define and drive the expression for electric susceptibility

Consider the diode circuit shown in the figure below:The input output characteristic curve of the circuit can be represented as(Assume cut-in voltage of diode D1 and D2 is equal to 0.7 V)

17.Explain the following statement- 'For electrostatic field, the closed integral of electric field w.r.t displacement is always 0, because electric force F = qE on a point charge is conservative.

A person is standing on a truck moving with a constant velocity of 14.7 m/s on a horizontal road. The man throws a ball in such a way that it returns to the truck after the truck has moved 58.8 m. Find the speed and the angle of projection (a) As seen from the truck, (b) Aa seen from the road.

A sphere rolls without slipping on an inclined plane of inclination . Then the minimum value of coefficient of friction so that the sphere rolls with out slipping is

A cylinder of radius r and of thermal conductivity k1 is surrounded by a cylindrical shell of inner radius r and outer radius 2r made of a material of thermal conductivity k2. The effective thermal conductivity of the system is

What is meant by refraction

A block placed on an inclined plane of slope angle θ slides down with a constant speed. The coefficient of kinetic friction is equal to (correct answer + 1, wrong answer - 0.25)