50278 + Interview Questions in Physics

1.	A conductor at 10∘C connected in the left gap of metre bridge gives balancing length 40 cm. When the conductor is at 60∘C, the balance point shifts by 5cm. The temperature coefficient of resistance of the material of the conductor is
Answer» A conductor at $10^{\circ}$ C connected in the left gap of metre bridge gives balancing length 40 cm. When the conductor is at $60^{\circ}$ C, the balance point shifts by 5cm. The temperature coefficient of resistance of the material of the conductor is

Discussion

2.	20.Y = cos wt + cos 3wt + cos 5wt In the equation of a periodic motion , the time period is given as T = 2π/w. How the time period is like that ?? Although, for each term time period s are 2π/w , 2π/3w , 2π/5w respectively.
Answer» 20.Y = cos wt + cos 3wt + cos 5wt In the equation of a periodic motion , the time period is given as T = 2π/w. How the time period is like that ?? Although, for each term time period s are 2π/w , 2π/3w , 2π/5w respectively.

Discussion

3.	A current of 2 A flows through a 2 Ω resistance when connected across a battery. The same battery supplies a current of 0.5 A when connected across a 9 Ω resistor. The internal resistance of the battery is
Answer» A current of 2 $A$ flows through a $2 Ω$ resistance when connected across a battery. The same battery supplies a current of 0.5 $A$ when connected across a $9 Ω$ resistor. The internal resistance of the battery is

Discussion

4.	A sphere of masss m and radius r rolls without slipping on a rough concave surface of large radius R .It makes small oscillations about the lowest point .Find time period .
Answer» A sphere of masss m and radius r rolls without slipping on a rough concave surface of large radius R .It makes small oscillations about the lowest point .Find time period .

Discussion

5.	Burst the bubbles that have balanced equations.
Answer» Burst the bubbles that have balanced equations.

Discussion

6.	Three rings each of mass M and radius R are arranged as shown. The moment of inertia of the system about YY' will be
Answer» Three rings each of mass $M$ and radius $R$ are arranged as shown. The moment of inertia of the system about $Y Y'$ will be

Discussion

7.	What is the equivalent resistance of a voltmeter with coil resistance Rc=1kΩ and series resistance of 100 kΩ?
Answer» What is the equivalent resistance of a voltmeter with coil resistance $R_{c} = 1 k Ω$ and series resistance of 100 k $Ω$ ?

Discussion

8.	Sam freely drops a pen, a ball, and a brick in a water tank. Tap the object on which the fluid friction will be minimum by closely observing its shape.
Answer» Sam freely drops a pen, a ball, and a brick in a water tank. Tap the object on which the fluid friction will be minimum by closely observing its shape.

Discussion

9.	A particle is executing a simple harmonic motion. Its maximum acceleration is α and maximum velocity is β. Then, its time period of vibration will be
Answer» A particle is executing a simple harmonic motion. Its maximum acceleration is $α$ and maximum velocity is $β$ . Then, its time period of vibration will be

Discussion

10.	Four bodies of masses 2, 3, 5 and 8 kg are placed at the four corners of a square of side 2m in an anti-clockwise order with the 2kg mass at the origin. The position of the CM of the system will be
Answer» Four bodies of masses 2, 3, 5 and 8 kg are placed at the four corners of a square of side 2m in an anti-clockwise order with the 2kg mass at the origin. The position of the CM of the system will be

Discussion

11.	If y=e4x sin2x, then dydx=?
Answer» If $y = e^{4 x} s i n 2 x$ , then $\frac{d y}{d x}$ =?

Discussion

12.	Two taps A and B can fill a tank in 1 5 hrs and 1 2 hrs respectively. There is an outlet tap C. If all the taps are opened together the tank will fill in 30 hrs. In how many hours tap C alone can empty the tank?
Answer» Two taps A and B can fill a tank in 1 5 hrs and 1 2 hrs respectively. There is an outlet tap C. If all the taps are opened together the tank will fill in 30 hrs. In how many hours tap C alone can empty the tank?

Discussion

13.	The minimum and maximum distances of a planetrevolving around sun are r and R. If the minimumspeed of planet on its trajectory is vo, its maximumspeed will beVoRVor22(3) 24) R2
Answer» The minimum and maximum distances of a planetrevolving around sun are r and R. If the minimumspeed of planet on its trajectory is vo, its maximumspeed will beVoRVor22(3) 24) R2

Discussion

14.	A particle moves in the x-y plane with a constant accerlation of 8m/s^2 making an angle 37 degree with the x axis . At t =0 the particle is at the origin and its velocity is 8m/s along x axis. Find velocity and the position of the particle at t=2s.
Answer» A particle moves in the x-y plane with a constant accerlation of 8m/s^2 making an angle 37 degree with the x axis . At t =0 the particle is at the origin and its velocity is 8m/s along x axis. Find velocity and the position of the particle at t=2s.

Discussion

15.	Find the value of θ in the diagram so that the projectile can hit the target. (Take g=10 m/s2)
Answer» Find the value of $θ$ in the diagram so that the projectile can hit the target. $(Take g = 10 m / s^{2})$

Discussion

16.	The power factor of the following circuit is
Answer» The power factor of the following circuit is

Discussion

17.	if in potentiometer experiment the resistance is increased in external curcuit then what happen to balencing point
Answer» if in potentiometer experiment the resistance is increased in external curcuit then what happen to balencing point

Discussion

18.	A beaker containing water is placed on the platform of a spring balance. The balance reads 1.5 kg. A stone of mass 0.5 kg and density 500 kg/m3 is immersed in water without touching the walls of the beaker. What will be the reading of spring balance now?
Answer» A beaker containing water is placed on the platform of a spring balance. The balance reads $1.5 kg$ . A stone of mass $0.5 kg$ and density $500 {kg/m}^{3}$ is immersed in water without touching the walls of the beaker. What will be the reading of spring balance now?

Discussion

19.	A ray of monochromatic light incident on the plane surface of separation between two media x and y with angle of incidence i in the medium x and angle of refraction r in the medium y. The graph shows the relation between sini and sinr. The speed of light in the medium y is n times that of in medium x. The value of n is
Answer» A ray of monochromatic light incident on the plane surface of separation between two media $x$ and $y$ with angle of incidence $i$ in the medium $x$ and angle of refraction $r$ in the medium $y$ . The graph shows the relation between $sin i$ and $sin r$ . The speed of light in the medium $y$ is $n$ times that of in medium $x .$ The value of $n$ is

Discussion

20.	A stretched string is vibrating in the second overtone, then the number of nodes and antinodes between the ends of the string are respectively:
Answer» A stretched string is vibrating in the second overtone, then the number of nodes and antinodes between the ends of the string are respectively:

Discussion

21.	A charged particle (charge q) is moving in a circle of radius R with uniform speed v .The associated magnetic moment (mu) is given by a) qvR/2b)qvR²c)qvR²/2d)qvR
Answer» A charged particle (charge q) is moving in a circle of radius R with uniform speed v .The associated magnetic moment (mu) is given by a) qvR/2 b)qvR² c)qvR²/2 d)qvR

Discussion

22.	a particle of mass 2kg ,executing SHM has amplitude 20cm and time period 1s .the max speed i
Answer» a particle of mass 2kg ,executing SHM has amplitude 20cm and time period 1s .the max speed i

Discussion

23.	A square loop of 2 m side is placed in xy-plane with its centre at the origin and sides along the coordinate axes. If the magnetic flux density in the region is given by,→B=(2ˆax+3ˆay+5ˆaz)e−0.5tWb/m2The emf induced in the loop at t = 10 sec will be _____ mV67.379
Answer» A square loop of 2 m side is placed in xy-plane with its centre at the origin and sides along the coordinate axes. If the magnetic flux density in the region is given by, $\to B = (2 {ˆ a}_{x} + 3 {ˆ a}_{y} + 5 {ˆ a}_{z}) e^{- 0.5 t} W b / m^{2}$ The emf induced in the loop at t = 10 sec will be _____ mV 67.379

Discussion

24.	A particle of mass 'm' and charge q moves at a high speed along the X axis. Initially it is near -infinity and then in a short time moves to positive infinity. Another charge Q is fixed at (0,-d) . As the moving charge passes the stationary charge, the X component of its velocity does not change appreciably but it acquires a small velocity in the y direction. Determine the angle through which the moving charge is deflected.
Answer» A particle of mass 'm' and charge q moves at a high speed along the X axis. Initially it is near -infinity and then in a short time moves to positive infinity. Another charge Q is fixed at (0,-d) . As the moving charge passes the stationary charge, the X component of its velocity does not change appreciably but it acquires a small velocity in the y direction. Determine the angle through which the moving charge is deflected.

Discussion

25.	34.What is the moment of inertia I1, I2 And I3?
Answer» 34.What is the moment of inertia I1, I2 And I3?

Discussion

26.	a round disc of moment of inertia I1 about its axis perpendicular to its plane and passing through its centre is placed over another disc of moment of inertia I2 rotating with an angular velocity w about same axis the final angular velocity of the combination of disc
Answer» a round disc of moment of inertia I1 about its axis perpendicular to its plane and passing through its centre is placed over another disc of moment of inertia I2 rotating with an angular velocity w about same axis the final angular velocity of the combination of disc

Discussion

27.	Is wave no. formula is for only hydrogen ,He,Li ion and Be ion or it is used for other atoms too?
Answer» Is wave no. formula is for only hydrogen ,He,Li ion and Be ion or it is used for other atoms too?

Discussion

28.	63.A long straight wire carrying current I1 is placed in the plane of a Ribbon carrying current I2 parallel to the wire. The width of the ribbon in 'b'. The straight conductor is placed at a distance 'a' from the nearer edge of the ribbon. Find the force of attraction per unit length between the two?
Answer» 63.A long straight wire carrying current I1 is placed in the plane of a Ribbon carrying current I2 parallel to the wire. The width of the ribbon in 'b'. The straight conductor is placed at a distance 'a' from the nearer edge of the ribbon. Find the force of attraction per unit length between the two?

Discussion

29.	7. What is mean by disjoint?Sets and draw a diagram for disjoint sets
Answer» 7. What is mean by disjoint?Sets and draw a diagram for disjoint sets

Discussion

30.	A source is moving with constant speed vs=20 m/s towards a stationary observer due east of the source. Wind is blowing at the speed of 20 m/s at 60∘ north of east. The source has frequency 1000 Hz. If the speed of sound is 310 m/s, the frequency observed by the observer is approximately
Answer» A source is moving with constant speed $v_{s} = 20 m/s$ towards a stationary observer due east of the source. Wind is blowing at the speed of $20 m/s$ at $60^{\circ}$ north of east. The source has frequency $1000 Hz$ . If the speed of sound is $310 m/s$ , the frequency observed by the observer is approximately

Discussion

31.	In the experimental arrangement shown in figure, the area of cross-section of the wide and narrow portions of the tube are 5 cm2 and 2 cm2 respectively. The rate of flow of water through the tube is 500 cm3 s−1. The difference of mercury levels in the U-tube is:
Answer» In the experimental arrangement shown in figure, the area of cross-section of the wide and narrow portions of the tube are $5 {cm}^{2}$ and $2 {cm}^{2}$ respectively. The rate of flow of water through the tube is $500 {cm}^{3} s^{- 1}$ . The difference of mercury levels in the U-tube is:

Discussion

32.	Hot water cools from 60∘C to 50∘C in the first 10 min and to 42∘C in the next 10 min. The temperature of the surrounding is
Answer» Hot water cools from $60^{\circ} C$ to $50^{\circ} C$ in the first $10 min$ and to $42^{\circ} C$ in the next $10 min$ . The temperature of the surrounding is

Discussion

33.	Let 'l' be the moment of inertia of an uniform square plate about an axis AB that passes through its centre and is parallel to two of its sides. CD is a line in the plane of the plate that passes through the centre of the plate and makes an angle θ with AB. The moment of inertia of the plate about the axis CD is then equal to
Answer» Let 'l' be the moment of inertia of an uniform square plate about an axis AB that passes through its centre and is parallel to two of its sides. CD is a line in the plane of the plate that passes through the centre of the plate and makes an angle $θ$ with AB. The moment of inertia of the plate about the axis CD is then equal to

33.

Let 'l' be the moment of inertia of an uniform square plate about an axis AB that passes through its centre and is parallel to two of its sides. CD is a line in the plane of the plate that passes through the centre of the plate and makes an angle θ with AB. The moment of inertia of the plate about the axis CD is then equal to

Answer»

Let 'l' be the moment of inertia of an uniform square plate about an axis AB that passes through its centre and is parallel to two of its sides. CD is a line in the plane of the plate that passes through the centre of the plate and makes an angle $θ$ with AB. The moment of inertia of the plate about the axis CD is then equal to

Discussion

34.	If threshold wavelength for sodium is 6800∘A then the work function will be
Answer» If threshold wavelength for sodium is $6800 \circ A$ then the work function will be

Discussion

35.	A uniform rod of mass M and length L is pivoted at one end such that it can rotate in a vertical plane. There is negligible friction at the pivot. The free end of the rod is held vertically above the pivot and then released. The angular acceleration of the rod when it makes an angle θ with the vertical is
Answer» A uniform rod of mass $M$ and length $L$ is pivoted at one end such that it can rotate in a vertical plane. There is negligible friction at the pivot. The free end of the rod is held vertically above the pivot and then released. The angular acceleration of the rod when it makes an angle $θ$ with the vertical is

Discussion

36.	A solenoid has 1000 turns, length of 30 cm and an area of cross-section 1.5×10−3 m2. Near to its centre , a coaxial coil of 500 turns is wounded. If a current changes through the solenoid at a rate of 8 A/s , then find the emf induced in the coil.
Answer» A solenoid has $1000$ turns, length of $30 cm$ and an area of cross-section $1.5 \times 10^{- 3} m^{2} .$ Near to its centre , a coaxial coil of $500$ turns is wounded. If a current changes through the solenoid at a rate of $8 A/s$ , then find the emf induced in the coil.

Discussion

37.	The given figure shows the cross section of a uniform pencil placed on a rough platform. The cross-section of the pencil is a hexagon of side ‘a′. The platform starts performing S.H.M. perpendicular to the length of the pencil in horizontal plane with angular frequency ‘ω′. There is sufficient friction between the pencil and the platform such that there is no slipping between them. The maximum amplitude of oscillations so that the pencil does not topple is g√αω2. Find α
Answer» The given figure shows the cross section of a uniform pencil placed on a rough platform. The cross-section of the pencil is a hexagon of side $‘ a^{'}$ . The platform starts performing S.H.M. perpendicular to the length of the pencil in horizontal plane with angular frequency $‘ ω^{'}$ . There is sufficient friction between the pencil and the platform such that there is no slipping between them. The maximum amplitude of oscillations so that the pencil does not topple is $\frac{g}{\sqrt{α} ω^{2}}$ . Find $α$

Discussion

38.	Adding which among the following to coil-1 will reduce the deflection in coil-2 the most?
Answer» Adding which among the following to coil-1 will reduce the deflection in coil-2 the most?

Discussion

39.	Why are the components of a single vector considered parallel to each other?
Answer» Why are the components of a single vector considered parallel to each other?

Discussion

40.	Two conducting wires are joined together and are moving in a magnetic field perpendicular to the plane of the wires, as shown in the figure. If VP and VQ are the potentials at points P and Q respectively, then -
Answer» Two conducting wires are joined together and are moving in a magnetic field perpendicular to the plane of the wires, as shown in the figure. If $V_{P}$ and $V_{Q}$ are the potentials at points $P$ and $Q$ respectively, then -

Discussion

41.	The value of the sum of two vectors →A and →B with \theta as the angle between them is
Answer» The value of the sum of two vectors $\to A$ and $\to B$ with \theta as the angle between them is

Discussion

42.	A hemispherical bowl of radius R is rotated about its axis of symmetry which is kept vertical .A small block is kept in the bowl at a position where the radius makes an angle θ with vertical .The block rotates with the bowl without any slipping .The friction coefficient between block and bwl surface is μ Find the range of the angular speed for whichblock will not slip
Answer» A hemispherical bowl of radius R is rotated about its axis of symmetry which is kept vertical .A small block is kept in the bowl at a position where the radius makes an angle θ with vertical .The block rotates with the bowl without any slipping .The friction coefficient between block and bwl surface is μ Find the range of the angular speed for whichblock will not slip

Discussion

43.	differentiate between AC and DC generators
Answer» differentiate between AC and DC generators

Discussion

44.	A passenger arriving in a new town wishes to go from the station to a hotel located 10 km away on a straight road from the station. A dishonest cabman takes him along a circuitous path 23 km long and reaches the hotel in 28 min. What is (a) the average speed of the taxi, (b) the magnitude of average velocity ? Are the two equal ?
Answer» A passenger arriving in a new town wishes to go from the station to a hotel located 10 km away on a straight road from the station. A dishonest cabman takes him along a circuitous path 23 km long and reaches the hotel in 28 min. What is (a) the average speed of the taxi, (b) the magnitude of average velocity ? Are the two equal ?

Discussion

45.	5.From a uniformly charged disc of radius R having surface charge density sigma , a disc of radius R/2 is removed as shown what is the electric potential at point P
Answer» 5.From a uniformly charged disc of radius R having surface charge density sigma , a disc of radius R/2 is removed as shown what is the electric potential at point P

Discussion

46.	Water rises in a capillarity tube to a height 2.0 cm. if the tube is inclined at an angle of 60° with the vertical, what will be the length of the water column within the tube?
Answer» Water rises in a capillarity tube to a height 2.0 cm. if the tube is inclined at an angle of 60° with the vertical, what will be the length of the water column within the tube?

Discussion

47.	An inductor of inductance L=5 H is connected to an AC source having voltage E=10sin(10t+π6). Find the maximum value of current in the circuit.
Answer» An inductor of inductance $L = 5 H$ is connected to an $AC$ source having voltage $E = 10 sin (10 t + \frac{π}{6})$ . Find the maximum value of current in the circuit.

Discussion

48.	Two bodies of masses ′m′ and ′4m′ are having linear momentum in the ratio of 2:1, respectively. The ratio of their kinetic energy is
Answer» Two bodies of masses $^{'} m^{'}$ and $^{'} 4 m^{'}$ are having linear momentum in the ratio of $2 : 1$ , respectively. The ratio of their kinetic energy is

Discussion

49.	The retarding acceleration of 7.35 ms−2 due to frictional force stops the car of mass 400 kg travelling on a road. The coefficient of friction between the tyre of the car and the road is
Answer» The retarding acceleration of $7.35 {ms}^{- 2}$ due to frictional force stops the car of mass $400 kg$ travelling on a road. The coefficient of friction between the tyre of the car and the road is

Discussion

50.	The magnetic lines of force inside a bar magnet
Answer» The magnetic lines of force inside a bar magnet

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

A conductor at 10∘C connected in the left gap of metre bridge gives balancing length 40 cm. When the conductor is at 60∘C, the balance point shifts by 5cm. The temperature coefficient of resistance of the material of the conductor is

20.Y = cos wt + cos 3wt + cos 5wt In the equation of a periodic motion , the time period is given as T = 2π/w. How the time period is like that ?? Although, for each term time period s are 2π/w , 2π/3w , 2π/5w respectively.

A current of 2 A flows through a 2 Ω resistance when connected across a battery. The same battery supplies a current of 0.5 A when connected across a 9 Ω resistor. The internal resistance of the battery is

A sphere of masss m and radius r rolls without slipping on a rough concave surface of large radius R .It makes small oscillations about the lowest point .Find time period .

Burst the bubbles that have balanced equations.

Three rings each of mass M and radius R are arranged as shown. The moment of inertia of the system about YY' will be

What is the equivalent resistance of a voltmeter with coil resistance Rc=1kΩ and series resistance of 100 kΩ?

Sam freely drops a pen, a ball, and a brick in a water tank. Tap the object on which the fluid friction will be minimum by closely observing its shape.

A particle is executing a simple harmonic motion. Its maximum acceleration is α and maximum velocity is β. Then, its time period of vibration will be

Four bodies of masses 2, 3, 5 and 8 kg are placed at the four corners of a square of side 2m in an anti-clockwise order with the 2kg mass at the origin. The position of the CM of the system will be

If y=e4x sin2x, then dydx=?

Two taps A and B can fill a tank in 1 5 hrs and 1 2 hrs respectively. There is an outlet tap C. If all the taps are opened together the tank will fill in 30 hrs. In how many hours tap C alone can empty the tank?

The minimum and maximum distances of a planetrevolving around sun are r and R. If the minimumspeed of planet on its trajectory is vo, its maximumspeed will beVoRVor22(3) 24) R2

A particle moves in the x-y plane with a constant accerlation of 8m/s^2 making an angle 37 degree with the x axis . At t =0 the particle is at the origin and its velocity is 8m/s along x axis. Find velocity and the position of the particle at t=2s.

Find the value of θ in the diagram so that the projectile can hit the target. (Take g=10 m/s2)

The power factor of the following circuit is

if in potentiometer experiment the resistance is increased in external curcuit then what happen to balencing point

A beaker containing water is placed on the platform of a spring balance. The balance reads 1.5 kg. A stone of mass 0.5 kg and density 500 kg/m3 is immersed in water without touching the walls of the beaker. What will be the reading of spring balance now?

A stretched string is vibrating in the second overtone, then the number of nodes and antinodes between the ends of the string are respectively:

A charged particle (charge q) is moving in a circle of radius R with uniform speed v .The associated magnetic moment (mu) is given by a) qvR/2b)qvR²c)qvR²/2d)qvR

a particle of mass 2kg ,executing SHM has amplitude 20cm and time period 1s .the max speed i

A square loop of 2 m side is placed in xy-plane with its centre at the origin and sides along the coordinate axes. If the magnetic flux density in the region is given by,→B=(2ˆax+3ˆay+5ˆaz)e−0.5tWb/m2The emf induced in the loop at t = 10 sec will be _____ mV67.379

34.What is the moment of inertia I1, I2 And I3?

a round disc of moment of inertia I1 about its axis perpendicular to its plane and passing through its centre is placed over another disc of moment of inertia I2 rotating with an angular velocity w about same axis the final angular velocity of the combination of disc

Is wave no. formula is for only hydrogen ,He,Li ion and Be ion or it is used for other atoms too?

7. What is mean by disjoint?Sets and draw a diagram for disjoint sets

A source is moving with constant speed vs=20 m/s towards a stationary observer due east of the source. Wind is blowing at the speed of 20 m/s at 60∘ north of east. The source has frequency 1000 Hz. If the speed of sound is 310 m/s, the frequency observed by the observer is approximately

In the experimental arrangement shown in figure, the area of cross-section of the wide and narrow portions of the tube are 5 cm2 and 2 cm2 respectively. The rate of flow of water through the tube is 500 cm3 s−1. The difference of mercury levels in the U-tube is:

Hot water cools from 60∘C to 50∘C in the first 10 min and to 42∘C in the next 10 min. The temperature of the surrounding is

If threshold wavelength for sodium is 6800∘A then the work function will be

A solenoid has 1000 turns, length of 30 cm and an area of cross-section 1.5×10−3 m2. Near to its centre , a coaxial coil of 500 turns is wounded. If a current changes through the solenoid at a rate of 8 A/s , then find the emf induced in the coil.

Adding which among the following to coil-1 will reduce the deflection in coil-2 the most?

Why are the components of a single vector considered parallel to each other?

Two conducting wires are joined together and are moving in a magnetic field perpendicular to the plane of the wires, as shown in the figure. If VP and VQ are the potentials at points P and Q respectively, then -

The value of the sum of two vectors →A and →B with \theta as the angle between them is

differentiate between AC and DC generators

5.From a uniformly charged disc of radius R having surface charge density sigma , a disc of radius R/2 is removed as shown what is the electric potential at point P

Water rises in a capillarity tube to a height 2.0 cm. if the tube is inclined at an angle of 60° with the vertical, what will be the length of the water column within the tube?

An inductor of inductance L=5 H is connected to an AC source having voltage E=10sin(10t+π6). Find the maximum value of current in the circuit.

Two bodies of masses ′m′ and ′4m′ are having linear momentum in the ratio of 2:1, respectively. The ratio of their kinetic energy is

The retarding acceleration of 7.35 ms−2 due to frictional force stops the car of mass 400 kg travelling on a road. The coefficient of friction between the tyre of the car and the road is

The magnetic lines of force inside a bar magnet