50278 + Interview Questions in Physics

1.	2. the ratio of mass of an electrol to that of the mass of hydrogen atom is 1 1:3871 2 1:1837 3 1:1296 4 1:3781
Answer» 2. the ratio of mass of an electrol to that of the mass of hydrogen atom is 1 1:3871 2 1:1837 3 1:1296 4 1:3781

Discussion

2.	A steel rod is streched along its length by 1 mm. The rod has initial length as 1 m and cross sectional area 0.01 m2. Young's modulus of steel is 2×1011 Pa. The potential energy stored in the steel rod assuming negligible change in volume due to streching of the rod is (in J):
Answer» A steel rod is streched along its length by $1 mm$ . The rod has initial length as $1 m$ and cross sectional area $0.01 m^{2}$ . Young's modulus of steel is $2 \times 10^{11} Pa$ . The potential energy stored in the steel rod assuming negligible change in volume due to streching of the rod is (in $J$ ):

Discussion

3.	Make a chart of circuit diagram of all logic gate
Answer» Make a chart of circuit diagram of all logic gate

Discussion

4.	A time varying force F=(2t)^j is acting on a particle of mass m=3 kg moving along y-axis. The velocity of the particle is −4^j m/s at time t=0. The velocity of the particle at the end of 4 s is
Answer» A time varying force $F = (2 t)^j$ is acting on a particle of mass $m = 3 kg$ moving along y-axis. The velocity of the particle is $- 4^j m/s$ at time $t = 0$ . The velocity of the particle at the end of $4 s$ is

Discussion

5.	Four solid spheres each of diameter √5 cm and mass 0.5 kg are placed with their centres at the corners of a square of side 4 cm. The moment of inertia of the system about the diagonal of the square is N×10−4 kg m2, then N is
Answer» Four solid spheres each of diameter $\sqrt{5} cm$ and mass $0.5 kg$ are placed with their centres at the corners of a square of side $4 cm$ . The moment of inertia of the system about the diagonal of the square is $N \times 10^{- 4} {kg m}^{2}$ , then $N$ is

Discussion

6.	Why does Potential Difference remain Constant when resistors are connected in a parallel way
Answer» Why does Potential Difference remain Constant when resistors are connected in a parallel way

Discussion

7.	Water flows in streamlined manner through a capillary tube of radius a, the pressure difference being P and the rate of flow Q. If the radius is reduced to a2 and the pressure increased to 2P, the rate of flow becomes
Answer» Water flows in streamlined manner through a capillary tube of radius a, the pressure difference being P and the rate of flow Q. If the radius is reduced to $\frac{a}{2}$ and the pressure increased to 2P, the rate of flow becomes

Discussion

8.	If in Hydrogen atom, an electron jumps from n2 = 2 to n1 = 1 in Bohr's orbit, then the value of wave number of the emitted photon will be (R = 109700 cm-1)
Answer» If in Hydrogen atom, an electron jumps from n₂ = 2 to n₁= 1 in Bohr's orbit, then the value of wave number of the emitted photon will be (R = 109700 cm^-1)

Discussion

9.	What do you infer from Sam’s letter to Charley?
Answer» What do you infer from Sam’s letter to Charley?

Discussion

10.	Assertion :- The time period of spring mass system is greater at equator then at poles. Reason :- Time period of spring mass system depends on gravity.
Answer» Assertion :- The time period of spring mass system is greater at equator then at poles. Reason :- Time period of spring mass system depends on gravity.

Discussion

11.	A steam power plant operates on a regenerative cycle with a single open feedwater heater as shown in the figure. For the state points showwn, the specific enthalpies are h1=3000 kJ/kg and h2=160 kJ/kg. The bleed to the feedwater heater is 25% of the boiler steam generation rate. The specific enthalpy at state 3 is _____ kJ/kg870
Answer» A steam power plant operates on a regenerative cycle with a single open feedwater heater as shown in the figure. For the state points showwn, the specific enthalpies are $h_{1} = 3000$ $k J / k g$ and $h_{2} = 160 k J / k g$ . The bleed to the feedwater heater is 25% of the boiler steam generation rate. The specific enthalpy at state 3 is _____ kJ/kg 870

Discussion

12.	Two sliders A and B connected by a light rigid rod 10 m long, move in two frictionless shafts as shown in the figure. If B starts from rest, determine the velocity of B in m/sec when x=6 m. Assume mA=mB=200 kg and mC=100 kg. Also, rod is vertical initially. (Take g=9.8 ms−2)
Answer» Two sliders $A$ and $B$ connected by a light rigid rod $10 m$ long, move in two frictionless shafts as shown in the figure. If $B$ starts from rest, determine the velocity of $B$ in $m/sec$ when $x = 6 m$ . Assume $m_{A} = m_{B} = 200 kg$ and $m_{C} = 100 kg$ . Also, rod is vertical initially. (Take $g = 9.8 {ms}^{- 2}$ )

Discussion

13.	An artificial satellite is moving around earth in a circular orbit with speed equal to one fourth the escape speed of a body. From the surface of earth the hight of satellite above earth's surface is (R = radius of earth)
Answer» An artificial satellite is moving around earth in a circular orbit with speed equal to one fourth the escape speed of a body. From the surface of earth the hight of satellite above earth's surface is (R = radius of earth)

Discussion

14.	A particle of mass 2m is projected at an angle of 45∘ with horizontal with a velocity of 20√2 ms−1. After 1 s explosion takes place and the particle is broken into two equal pieces. As a result of the explosion, one part comes to rest. Find the maximum height (in metre) from initial point of the particle, attained by the other part is [Take g=10 ms−2]
Answer» A particle of mass $2 m$ is projected at an angle of $45^{\circ}$ with horizontal with a velocity of $20 \sqrt{2} {ms}^{- 1}$ . After $1 s$ explosion takes place and the particle is broken into two equal pieces. As a result of the explosion, one part comes to rest. Find the maximum height $(in metre)$ from initial point of the particle, attained by the other part is [Take $g = 10 {ms}^{- 2}$ ]

Discussion

15.	A refrigerator door is 150 cm high, 80 cm wide and 6 cm thick. If the coefficient of conductivity is 0.0005 cal/cm-s-∘C and the inner and outer surfaces are at 0∘C and 30∘C respectively, find the heat loss per minute through the door. (in Calories)
Answer» A refrigerator door is $150 cm$ high, $80 cm$ wide and $6 cm$ thick. If the coefficient of conductivity is $0.0005 {cal/cm-s-}^{\circ} C$ and the inner and outer surfaces are at $0^{\circ} C$ and $30^{\circ} C$ respectively, find the heat loss per minute through the door. (in Calories)

Discussion

16.	a horizontal disc rotating freely about a vertical axis through its axis makes 90 revolutions per minute . a small piece of wax falls vertically on the disc and sticks at distance r from the axis if the number of revolution reduces to 60 then moment of inertia of the disc is? why the moment of inertia of disc is taken MR^2 instead of MR^2/2 ??
Answer» a horizontal disc rotating freely about a vertical axis through its axis makes 90 revolutions per minute . a small piece of wax falls vertically on the disc and sticks at distance r from the axis if the number of revolution reduces to 60 then moment of inertia of the disc is? why the moment of inertia of disc is taken MR^2 instead of MR^2/2 ??

Discussion

17.	In a given system of units, 1 unit of mass=2 Kg, 1 unit of length=5m, 1 unit of time=5. then in this system, 1N represents(1)5/2 units of force(2)2/5 units of force(3)2 units of force (4)1/2 units of force
Answer» In a given system of units, 1 unit of mass=2 Kg, 1 unit of length=5m, 1 unit of time=5. then in this system, 1N represents (1)5/2 units of force (2)2/5 units of force (3)2 units of force (4)1/2 units of force

Discussion

18.	A vector has a magnitude 12. When its tail is at origin, it lies between the positive x - axis and the negative y - axis and makes an angle 30∘ with the x- axis. It’s y - component is
Answer» A vector has a magnitude $12$ . When its tail is at origin, it lies between the positive x - axis and the negative y - axis and makes an angle $30^{\circ}$ with the x- axis. It’s y - component is

Discussion

19.	Ratio of active masses of 22gm CO_2,3gm H_2 and 7gm N_2 in a gaseous mixture:
Answer» Ratio of active masses of 22gm CO_2,3gm H_2 and 7gm N_2 in a gaseous mixture:

Discussion

20.	The variation of magnetic susceptibility (χ) with temperature for a diamagnetic substance is best represented by
Answer» The variation of magnetic susceptibility $(χ)$ with temperature for a diamagnetic substance is best represented by

Discussion

21.	A rod is bent into a semi-circular arc of radius R. The rod has a uniform linear charge distribution A. Thepotential at the centre of the arc, point P is
Answer» A rod is bent into a semi-circular arc of radius R. The rod has a uniform linear charge distribution A. Thepotential at the centre of the arc, point P is

Discussion

22.	A body of mass 2m is moving in positive X axis and a body of mass m moving with 10^1/3m/s in the positive Y axis collides at the origin and moves 60 degrees along X- axis. Find the initial velocity of the first body.
Answer» A body of mass 2m is moving in positive X axis and a body of mass m moving with 10^1/3m/s in the positive Y axis collides at the origin and moves 60 degrees along X- axis. Find the initial velocity of the first body.

Discussion

23.	The equivalent capacitance(in μF) between points A and B of the circuit will be (given : C=1.3 μF)
Answer» The equivalent capacitance(in $μ F$ ) between points $A$ and $B$ of the circuit will be (given : $C = 1.3 μ F$ )

Discussion

24.	A bulb of 100 W−250 V is connected to 250 V mains. If another similar bulb is connected to it in series, the total power consumption(in W) is
Answer» A bulb of $100 W - 250 V$ is connected to $250 V$ mains. If another similar bulb is connected to it in series, the total power consumption(in $W$ ) is

Discussion

25.	Find the area of the parallelogram whose adjacent sides are determined by the vectors a=^i−^j+3^k and b=2^i−7^j+^k
Answer» Find the area of the parallelogram whose adjacent sides are determined by the vectors $a =^i -^j + 3^k$ and $b = 2^i - 7^j +^k$

Discussion

26.	On a nonnonducting ring of radius R +q and -q charges are uniformly distributed to the two halves the electric field intensity on the axis at diastance d
Answer» On a nonnonducting ring of radius R +q and -q charges are uniformly distributed to the two halves the electric field intensity on the axis at diastance d

Discussion

27.	A perfect black body of surface area 1 cm2 is heated to a temperature 1000 K. The amount of energy radiated by the body in 1 s is (Stefan’s constant σ=5.67×10−8 Wm−2K−4)
Answer» A perfect black body of surface area $1 {cm}^{2}$ is heated to a temperature $1000 K$ . The amount of energy radiated by the body in $1 s$ is (Stefan’s constant $σ = 5.67 \times 10^{- 8} W m^{- 2} K^{- 4}$ )

Discussion

28.	A sand bag of mass M is suspended by rope. Abullet of mass m is fired at it with speed v and thebullet gets embedded in it. The loss of kineticenergy in the collision is(1) 2(M+m)(2) 2(M+m)m2v2(3) 2(M+m)frauw()
Answer» A sand bag of mass M is suspended by rope. Abullet of mass m is fired at it with speed v and thebullet gets embedded in it. The loss of kineticenergy in the collision is(1) 2(M+m)(2) 2(M+m)m2v2(3) 2(M+m)frauw()

Discussion

29.	What is x ray diffraction through which the radius is found?
Answer» What is x ray diffraction through which the radius is found?

Discussion

30.	5.Why the gravitational force of moon and sun doesn't affect on us but affects the sea water to rise up and form tides ?
Answer» 5.Why the gravitational force of moon and sun doesn't affect on us but affects the sea water to rise up and form tides ?

Discussion

31.	I am still confuse in real and ideal gas
Answer» I am still confuse in real and ideal gas

Discussion

32.	The shunt resistance needed for a galvanometer of 500 Ω to decreases its sensitivity by 100 times is
Answer» The shunt resistance needed for a galvanometer of $500 Ω$ to decreases its sensitivity by $100$ times is

Discussion

33.	How did Huygen explain the absence of the back wave? Use this principle to draw therefracted wave front for a plane wavefront incident from a denser to a rarer medium.Hence obtain Snell law of refraction.
Answer» How did Huygen explain the absence of the back wave? Use this principle to draw the refracted wave front for a plane wavefront incident from a denser to a rarer medium. Hence obtain Snell law of refraction.

Discussion

34.	Three infinitely long line charges are arranged along the three co-ordinate axes. The magnitude of electric field at a point P (a, a, a) is:Lambda is the charge per unit length on each line charge.
Answer» Three infinitely long line charges are arranged along the three co-ordinate axes. The magnitude of electric field at a point P (a, a, a) is: Lambda is the charge per unit length on each line charge.

Discussion

35.	For the given semi-infinite rod, if a positive test charge at rest is kept at point P, then it will take path
Answer» For the given semi-infinite rod, if a positive test charge at rest is kept at point $P$ , then it will take path

Discussion

36.	Which of these following transformers for per unit loading will reach full load first ?
Answer» Which of these following transformers for per unit loading will reach full load first ?

Discussion

37.	The difference between the apparent frequency of a source as perceived by an observer during its approach and recession is 2 percent of the natural frequency of the source. The velocity of the source is
Answer» The difference between the apparent frequency of a source as perceived by an observer during its approach and recession is 2 percent of the natural frequency of the source. The velocity of the source is

Discussion

38.	An AC supply with constant peak voltage and variable frequency is applied across a capacitor of capacitance C. Which of the following graphs correctly depicts the variation of peak current (i) with angular frequency (ω)?
Answer» An AC supply with constant peak voltage and variable frequency is applied across a capacitor of capacitance $C$ . Which of the following graphs correctly depicts the variation of peak current $(i)$ with angular frequency $(ω)$ ?

Discussion

39.	A body is thrown horizontally from the top of a tower and strikes the ground after three seconds at an angle of 45∘ with the horizontal. Find the height of the tower and the speed with which the body was projected. Take g=9.8m/s2
Answer» A body is thrown horizontally from the top of a tower and strikes the ground after three seconds at an angle of $45^{\circ}$ with the horizontal. Find the height of the tower and the speed with which the body was projected. Take $g = 9.8 m / s^{2}$

Discussion

40.	12 g He and 4 g H2 filled in a container of volume 20 L maintained at temperature 300 K. The pressure of the mixture is nearly
Answer» $12 g$ $He$ and $4 g H_{2}$ filled in a container of volume $20 L$ maintained at temperature $300 K$ . The pressure of the mixture is nearly

Discussion

41.	A Light source that radiates 10 Joules of energy per second is kept at the centre of a hemisphere. How much energy will the hemisphere receive?Energy (in Joules) =
Answer» A Light source that radiates 10 Joules of energy per second is kept at the centre of a hemisphere. How much energy will the hemisphere receive? Energy (in Joules) =

41.

A Light source that radiates 10 Joules of energy per second is kept at the centre of a hemisphere. How much energy will the hemisphere receive?Energy (in Joules) =

Answer»

A Light source that radiates 10 Joules of energy per second is kept at the centre of a hemisphere. How much energy will the hemisphere receive?

Energy (in Joules) =

Discussion

42.	A force of 98 N is required to just start moving a body of mass 100 kg over ice. The coiefficient of static friction
Answer» A force of 98 N is required to just start moving a body of mass 100 kg over ice. The coiefficient of static friction

Discussion

43.	In △ABC sides opposite to angles A,B,C are denoted by a,b,c respectively. Then the maximum value of a2+b2+c2R2=(where R is circumradius)
Answer» In $△ A B C$ sides opposite to angles $A, B, C$ are denoted by $a, b, c$ respectively. Then the maximum value of $\frac{a^{2} + b^{2} + c^{2}}{R^{2}} =$ (where $R$ is circumradius)

Discussion

44.	The heat generated in the coil of resistance 180 ohm which is connected to a silver voltmeter is 364.5 kj . If a steady current is passed through the circuit for15 min , find the mass of Ag that gets deposited on the cathode . Relative atomic mass of silver is 108 gm and faraday constant is 96500 c.
Answer» The heat generated in the coil of resistance 180 ohm which is connected to a silver voltmeter is 364.5 kj . If a steady current is passed through the circuit for15 min , find the mass of Ag that gets deposited on the cathode . Relative atomic mass of silver is 108 gm and faraday constant is 96500 c.

Discussion

45.	The velocity of an electromagnetic wave is parallel to
Answer» The velocity of an electromagnetic wave is parallel to

Discussion

46.	the speed at the maximum height of a projection is half of its initial speed of projection(u) . the horizontal range of projectile is
Answer» the speed at the maximum height of a projection is half of its initial speed of projection(u) . the horizontal range of projectile is

Discussion

47.	Double-convex lenses are to be manufactured from a glass ofrefractive index 1.55, with both faces of the same radius ofcurvature. What is the radius of curvature required if the focal lengthis to be 20cm?
Answer» Double-convex lenses are to be manufactured from a glass ofrefractive index 1.55, with both faces of the same radius ofcurvature. What is the radius of curvature required if the focal lengthis to be 20cm?

Discussion

48.	A body of mass m is launched up on a rough inclined plane making an angle of 30∘ with the horizontal. The coefficient of friction between the body and plane is √x5 if the time of ascent is half of the time of descent. The value of x is ______.
Answer» A body of mass $m$ is launched up on a rough inclined plane making an angle of $30^{\circ}$ with the horizontal. The coefficient of friction between the body and plane is $\frac{\sqrt{x}}{5}$ if the time of ascent is half of the time of descent. The value of $x$ is ______.

Discussion

49.	A body A is projected upwards with a velocity of 98 m/s. The second body B is projected upwards with the same initial velocity but after 4 sec. Both the bodies will meet after
Answer» A body A is projected upwards with a velocity of 98 m/s. The second body B is projected upwards with the same initial velocity but after 4 sec. Both the bodies will meet after

Discussion

50.	Two short bar magnets of magnetic moments ‘M′ each are arranged at the opposite corners of a square of side ‘d′ such that their centres coincide with the corners and their axes are parallel to one side of the square. If the like poles are in the same direction, the magnetic induction at any of the other corners of the square is.
Answer» Two short bar magnets of magnetic moments $‘ M^{'}$ each are arranged at the opposite corners of a square of side $‘ d^{'}$ such that their centres coincide with the corners and their axes are parallel to one side of the square. If the like poles are in the same direction, the magnetic induction at any of the other corners of the square is.

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

2. the ratio of mass of an electrol to that of the mass of hydrogen atom is 1 1:3871 2 1:1837 3 1:1296 4 1:3781

A steel rod is streched along its length by 1 mm. The rod has initial length as 1 m and cross sectional area 0.01 m2. Young's modulus of steel is 2×1011 Pa. The potential energy stored in the steel rod assuming negligible change in volume due to streching of the rod is (in J):

Make a chart of circuit diagram of all logic gate

A time varying force F=(2t)^j is acting on a particle of mass m=3 kg moving along y-axis. The velocity of the particle is −4^j m/s at time t=0. The velocity of the particle at the end of 4 s is

Four solid spheres each of diameter √5 cm and mass 0.5 kg are placed with their centres at the corners of a square of side 4 cm. The moment of inertia of the system about the diagonal of the square is N×10−4 kg m2, then N is

Why does Potential Difference remain Constant when resistors are connected in a parallel way

Water flows in streamlined manner through a capillary tube of radius a, the pressure difference being P and the rate of flow Q. If the radius is reduced to a2 and the pressure increased to 2P, the rate of flow becomes

If in Hydrogen atom, an electron jumps from n2 = 2 to n1 = 1 in Bohr's orbit, then the value of wave number of the emitted photon will be (R = 109700 cm-1)

What do you infer from Sam’s letter to Charley?

Assertion :- The time period of spring mass system is greater at equator then at poles. Reason :- Time period of spring mass system depends on gravity.

Two sliders A and B connected by a light rigid rod 10 m long, move in two frictionless shafts as shown in the figure. If B starts from rest, determine the velocity of B in m/sec when x=6 m. Assume mA=mB=200 kg and mC=100 kg. Also, rod is vertical initially. (Take g=9.8 ms−2)

An artificial satellite is moving around earth in a circular orbit with speed equal to one fourth the escape speed of a body. From the surface of earth the hight of satellite above earth's surface is (R = radius of earth)

A refrigerator door is 150 cm high, 80 cm wide and 6 cm thick. If the coefficient of conductivity is 0.0005 cal/cm-s-∘C and the inner and outer surfaces are at 0∘C and 30∘C respectively, find the heat loss per minute through the door. (in Calories)

In a given system of units, 1 unit of mass=2 Kg, 1 unit of length=5m, 1 unit of time=5. then in this system, 1N represents(1)5/2 units of force(2)2/5 units of force(3)2 units of force (4)1/2 units of force

A vector has a magnitude 12. When its tail is at origin, it lies between the positive x - axis and the negative y - axis and makes an angle 30∘ with the x- axis. It’s y - component is

Ratio of active masses of 22gm CO_2,3gm H_2 and 7gm N_2 in a gaseous mixture:

The variation of magnetic susceptibility (χ) with temperature for a diamagnetic substance is best represented by

A rod is bent into a semi-circular arc of radius R. The rod has a uniform linear charge distribution A. Thepotential at the centre of the arc, point P is

A body of mass 2m is moving in positive X axis and a body of mass m moving with 10^1/3m/s in the positive Y axis collides at the origin and moves 60 degrees along X- axis. Find the initial velocity of the first body.

The equivalent capacitance(in μF) between points A and B of the circuit will be (given : C=1.3 μF)

A bulb of 100 W−250 V is connected to 250 V mains. If another similar bulb is connected to it in series, the total power consumption(in W) is

Find the area of the parallelogram whose adjacent sides are determined by the vectors a=^i−^j+3^k and b=2^i−7^j+^k

On a nonnonducting ring of radius R +q and -q charges are uniformly distributed to the two halves the electric field intensity on the axis at diastance d

A perfect black body of surface area 1 cm2 is heated to a temperature 1000 K. The amount of energy radiated by the body in 1 s is (Stefan’s constant σ=5.67×10−8 Wm−2K−4)

A sand bag of mass M is suspended by rope. Abullet of mass m is fired at it with speed v and thebullet gets embedded in it. The loss of kineticenergy in the collision is(1) 2(M+m)(2) 2(M+m)m2v2(3) 2(M+m)frauw()

What is x ray diffraction through which the radius is found?

5.Why the gravitational force of moon and sun doesn't affect on us but affects the sea water to rise up and form tides ?

I am still confuse in real and ideal gas

The shunt resistance needed for a galvanometer of 500 Ω to decreases its sensitivity by 100 times is

How did Huygen explain the absence of the back wave? Use this principle to draw therefracted wave front for a plane wavefront incident from a denser to a rarer medium.Hence obtain Snell law of refraction.

Three infinitely long line charges are arranged along the three co-ordinate axes. The magnitude of electric field at a point P (a, a, a) is:Lambda is the charge per unit length on each line charge.

For the given semi-infinite rod, if a positive test charge at rest is kept at point P, then it will take path

Which of these following transformers for per unit loading will reach full load first ?

The difference between the apparent frequency of a source as perceived by an observer during its approach and recession is 2 percent of the natural frequency of the source. The velocity of the source is

An AC supply with constant peak voltage and variable frequency is applied across a capacitor of capacitance C. Which of the following graphs correctly depicts the variation of peak current (i) with angular frequency (ω)?

A body is thrown horizontally from the top of a tower and strikes the ground after three seconds at an angle of 45∘ with the horizontal. Find the height of the tower and the speed with which the body was projected. Take g=9.8m/s2

12 g He and 4 g H2 filled in a container of volume 20 L maintained at temperature 300 K. The pressure of the mixture is nearly

A Light source that radiates 10 Joules of energy per second is kept at the centre of a hemisphere. How much energy will the hemisphere receive?Energy (in Joules) =

A force of 98 N is required to just start moving a body of mass 100 kg over ice. The coiefficient of static friction

In △ABC sides opposite to angles A,B,C are denoted by a,b,c respectively. Then the maximum value of a2+b2+c2R2=(where R is circumradius)

The velocity of an electromagnetic wave is parallel to

the speed at the maximum height of a projection is half of its initial speed of projection(u) . the horizontal range of projectile is

Double-convex lenses are to be manufactured from a glass ofrefractive index 1.55, with both faces of the same radius ofcurvature. What is the radius of curvature required if the focal lengthis to be 20cm?

A body of mass m is launched up on a rough inclined plane making an angle of 30∘ with the horizontal. The coefficient of friction between the body and plane is √x5 if the time of ascent is half of the time of descent. The value of x is ______.

A body A is projected upwards with a velocity of 98 m/s. The second body B is projected upwards with the same initial velocity but after 4 sec. Both the bodies will meet after