50278 + Interview Questions in Physics Page 63 InterviewSolution

3101.	Why the zero between two nonzero numbers(such as 2018) is significant?
Answer» Why the zero between two nonzero numbers(such as 2018) is significant?

Discussion

3102.	Which one of the following pattern of electrostatic lines of force is not possible?
Answer» Which one of the following pattern of electrostatic lines of force is not possible?

Discussion

3103.	How do you know that the distance between centre of mass and the centre of the circle is 2rπ
Answer» How do you know that the distance between centre of mass and the centre of the circle is $\frac{2 r}{π}$

Discussion

3104.	If speed of light (C),force(F),kinetic energy(K) are taken as fundamental units then dimension of mass will be
Answer» If speed of light (C),force(F),kinetic energy(K) are taken as fundamental units then dimension of mass will be

Discussion

3105.	the ground state energy of hydrogen atom id -13.6 eV when its e is in first excited state its excitation energy i
Answer» the ground state energy of hydrogen atom id -13.6 eV when its e is in first excited state its excitation energy i

Discussion

3106.	Sounds from two identical sources S1 and S2 reach a point P directly in the same phase with net intensity I0. The power of S1 is now reduced to 64% of its initial value, and the phase difference between S1 and S2 is varied continuously. The maximum and minimum intensities now recorded at P are Imax and Imin respectively. Then
Answer» Sounds from two identical sources $S_{1}$ and $S_{2}$ reach a point P directly in the same phase with net intensity $I_{0}$ . The power of $S_{1}$ is now reduced to 64% of its initial value, and the phase difference between $S_{1}$ and $S_{2}$ is varied continuously. The maximum and minimum intensities now recorded at P are $I_{m a x}$ and $I_{m i n}$ respectively. Then

Discussion

3107.	A mass m is suspended from the two coupled springs connected in series. The force constant for springs are K1 and K2. The time period of the suspended mass will be
Answer» A mass m is suspended from the two coupled springs connected in series. The force constant for springs are $K_{1}$ and $K_{2}$ . The time period of the suspended mass will be

3107.

A mass m is suspended from the two coupled springs connected in series. The force constant for springs are K1 and K2. The time period of the suspended mass will be

Answer»

A mass m is suspended from the two coupled springs connected in series. The force constant for springs are $K_{1}$ and $K_{2}$ . The time period of the suspended mass will be

Discussion

3108.	The cut off wavelength of continuous X-ray from two Coolidge tubes operating at 30 kV but using different target materials (molybdenum Z= 42 and tungsten Z = 74) are
Answer» The cut off wavelength of continuous X-ray from two Coolidge tubes operating at 30 kV but using different target materials (molybdenum Z= 42 and tungsten Z = 74) are

Discussion

3109.	15.Radius of He nucleus is 3 fermi. The radius of 16 S 32 nucleus will be
Answer» 15.Radius of He nucleus is 3 fermi. The radius of 16 S 32 nucleus will be

Discussion

3110.	Two thin charged metal plates are kept close to each other parallely. if the surface charge densities of each plant on their surface is 2.65 * 10-10 c/m2and -2.65* 10-10c/m2 respectively then the net electric field in between the nearly plates is ?
Answer» Two thin charged metal plates are kept close to each other parallely. if the surface charge densities of each plant on their surface is 2.65 * 10-10 c/m2 and -2.65* 10-10c/m2 respectively then the net electric field in between the nearly plates is ?

Discussion

3111.	Derivation of expression for minimum value of coefficient of friction for body to roll without slipping.
Answer» Derivation of expression for minimum value of coefficient of friction for body to roll without slipping.

Discussion

3112.	When an a.c. voltage is applied across series combination of a resistance R and an inductor of inductance 2 milli Henry, the phase difference between current and applied voltage is π6 radian. When same a.c. voltage is applied across series combination of same resistance and a condenser of capacity , 5μ F the phase difference between current and applied voltage is π3 radian. The value of R is
Answer» When an a.c. voltage is applied across series combination of a resistance R and an inductor of inductance 2 milli Henry, the phase difference between current and applied voltage is $\frac{π}{6}$ radian. When same a.c. voltage is applied across series combination of same resistance and a condenser of capacity , $5 μ F$ the phase difference between current and applied voltage is $\frac{π}{3}$ radian. The value of R is

3112.

When an a.c. voltage is applied across series combination of a resistance R and an inductor of inductance 2 milli Henry, the phase difference between current and applied voltage is π6 radian. When same a.c. voltage is applied across series combination of same resistance and a condenser of capacity , 5μ F the phase difference between current and applied voltage is π3 radian. The value of R is

Answer»

When an a.c. voltage is applied across series combination of a resistance R and an inductor of

inductance 2 milli Henry, the phase difference between current and applied voltage is $\frac{π}{6}$ radian.

When same a.c. voltage is applied across series combination of same resistance and a condenser of

capacity , $5 μ F$ the phase difference between current and applied voltage is $\frac{π}{3}$ radian. The value of

R is

Discussion

3113.	Two blocks of masses 2kg and 4 kg are hanging with the help of massless string passing over an ideal pulley inside an elevator. The elevator is moving upward with an acceleration of g/2.the tension in the string connected between the two blocks will be.
Answer» Two blocks of masses 2kg and 4 kg are hanging with the help of massless string passing over an ideal pulley inside an elevator. The elevator is moving upward with an acceleration of g/2.the tension in the string connected between the two blocks will be.

Discussion

3114.	ntConsider a vehicle going on a horizontal road towards east.Neglect any force by the air.The frictional force on the vehicle by the roadn nta)is zero if the vehicle is moving with a uniform velocityn ntb)is towards east if the vehicle is acceleratingn ntc)must be towards eastn ntd)must be towards westn
Answer» ntConsider a vehicle going on a horizontal road towards east.Neglect any force by the air.The frictional force on the vehicle by the roadn nta)is zero if the vehicle is moving with a uniform velocityn ntb)is towards east if the vehicle is acceleratingn ntc)must be towards eastn ntd)must be towards westn

Discussion

3115.	Two particles each of mass M are connected at the two ends of a spring of force constant K . The whole system lie on a smooth horizontal plane . If the particles are pushed to compressed the spring and then released ,then frequency of oscillation is?
Answer» Two particles each of mass M are connected at the two ends of a spring of force constant K . The whole system lie on a smooth horizontal plane . If the particles are pushed to compressed the spring and then released ,then frequency of oscillation is?

Discussion

3116.	A charge Q is uniformly distributed over a largesquare plate of copper. The electric field at a pointvery close to the centre of the plate is 10 V/m. Ifthe copper plate is replaced by a plastic plate of thesame geometrical dimensions and carrying thesame charge Q uniformly distributed, then theelectric field at the point P will be :-(1) 5 V/m (2) Zero(3) 10 V/m (4) 20 V/m
Answer» A charge Q is uniformly distributed over a large square plate of copper. The electric field at a point very close to the centre of the plate is 10 V/m. If the copper plate is replaced by a plastic plate of the same geometrical dimensions and carrying the same charge Q uniformly distributed, then the electric field at the point P will be :- (1) 5 V/m (2) Zero (3) 10 V/m (4) 20 V/m

Discussion

3117.	A vessel containing water has a constant acceleration of 19.6 m/s2 along horizontal direction. The free surface of water will be inclined with the horizontal at an angle of : [Take g=9.8 m/s2]
Answer» A vessel containing water has a constant acceleration of $19.6 {m/s}^{2}$ along horizontal direction. The free surface of water will be inclined with the horizontal at an angle of : [Take $g = 9.8 {m/s}^{2}$ ]

Discussion

3118.	A body is thrown with velocity 20 m/s at an angle of 60o with the horizontal. The time gap (in s) between the two positions of body where velocity of body makes an angle of 30o with horizontal is
Answer» A body is thrown with velocity $20 m / s$ at an angle of $60^{o}$ with the horizontal. The time gap (in $s$ ) between the two positions of body where velocity of body makes an angle of $30^{o}$ with horizontal is

Discussion

3119.	If a function is given as y=ln(sinx), then the first derivative of y w.r.t. x will be
Answer» If a function is given as $y = l n (s i n x)$ , then the first derivative of $y$ w.r.t. $x$ will be

Discussion

3120.	60% of given sample of oxygen gas when raised to a high temperature dissociates into atoms.Ratio of its initial heat capacity(at const. vol.) to the final heat capacity(at const. vol.) will be-1)8/7, 2)25/26, 3)10/7,4)25/27
Answer» 60% of given sample of oxygen gas when raised to a high temperature dissociates into atoms.Ratio of its initial heat capacity(at const. vol.) to the final heat capacity(at const. vol.) will be-1)8/7, 2)25/26, 3)10/7,4)25/27

Discussion

3121.	A particle of mass 10 kg is dropped from tower of height 10 m. Find the ratio of workdone by gravity from point ′A′ to ′B′ and change in potential energy from ′A′ to ′B′
Answer» A particle of mass $10 kg$ is dropped from tower of height $10 m$ . Find the ratio of workdone by gravity from point $^{'} A^{'}$ to $^{'} B^{'}$ and change in potential energy from $^{'} A^{'}$ to $^{'} B^{'}$

Discussion

3122.	Four blocks are arranged on a smooth horizontal surface as shown in the figure. The maximum value of horizontal force F, applied to one of the bottom blocks that makes all four blocks move with the same acceleration, is -
Answer» Four blocks are arranged on a smooth horizontal surface as shown in the figure. The maximum value of horizontal force $F$ , applied to one of the bottom blocks that makes all four blocks move with the same acceleration, is -

Discussion

3123.	an object is thrown up with speed 49 m/s. At what ins†an ts is it 19.6 m below the highest point
Answer» an object is thrown up with speed 49 m/s. At what ins†an ts is it 19.6 m below the highest point

Discussion

3124.	One light year is approximately equal to
Answer» One light year is approximately equal to

Discussion

3125.	An object is placed at a distance 2f from the pole of a convex mirror of focal length f. Themagnification is
Answer» An object is placed at a distance 2f from the pole of a convex mirror of focal length f. Themagnification is

Discussion

3126.	A ray of light going from denser to rarer medium suffers refraction at a concave surface. Which of the following relations is correct?
Answer» A ray of light going from denser to rarer medium suffers refraction at a concave surface. Which of the following relations is correct?

Discussion

3127.	When a semiconducting material is doped with an impurity, new acceptor levels are created. In a particular thermal collision, a valence electron receives an energy equal to 2kT and just reaches one of the acceptor levels. Assuming that the energy of the electron was at the top edge of the valence band and that the temperature T is equal to 300 K, find the energy of the acceptor levels above the valence band.
Answer» When a semiconducting material is doped with an impurity, new acceptor levels are created. In a particular thermal collision, a valence electron receives an energy equal to 2kT and just reaches one of the acceptor levels. Assuming that the energy of the electron was at the top edge of the valence band and that the temperature T is equal to 300 K, find the energy of the acceptor levels above the valence band.

Discussion

3128.	Three point charges are placed at the corners of an equilateral triangle Assuming only electrostatic forces are acting (a) The system can never be in equilibrium (b) The system will be in equilibrium if the charges rotate about the centre of the triangle (c) The system will be in equlibrium if the charges have different magnitudes and different signs (d) The system will be in equilibrium if the charges have the same magnitude but different signs
Answer» Three point charges are placed at the corners of an equilateral triangle Assuming only electrostatic forces are acting (a) The system can never be in equilibrium (b) The system will be in equilibrium if the charges rotate about the centre of the triangle (c) The system will be in equlibrium if the charges have different magnitudes and different signs (d) The system will be in equilibrium if the charges have the same magnitude but different signs

Discussion

3129.	Out of the following which one is independent of the other two?? wave velocity frequency wavelength
Answer» Out of the following which one is independent of the other two?? wave velocity frequency wavelength

Discussion

3130.	A photon in motion has a mass
Answer» A photon in motion has a mass

Discussion

3131.

Match the following: Column-IColumn-II(i). Infinite sheet of charge having positive charges.(a). Uniform non-zero electric field intensity in the vicinity.(ii). At the center of Non-conducting uniformly charged solid sphere.(b). Uniform decreasing potential in the vicinity.(iii). Inside a positively charged conducting sphere taking infinity as a reference point.(c). maximum magnitude of potential.

Answer»

Match the following:

Column- $I$	Column- $II$
$(i) .$ Infinite sheet of charge having positive charges.	$(a) .$ Uniform non-zero electric field intensity in the vicinity.
$(ii) .$ At the center of Non-conducting uniformly charged solid sphere.	$(b) .$ Uniform decreasing potential in the vicinity.
$(iii) .$ Inside a positively charged conducting sphere taking infinity as a reference point.	$(c) .$ maximum magnitude of potential.

Discussion

3132.	A block of mass 4 kg carrying a charge 50 μC is connected to a spring for which spring constant is 100 N/m. The block lies on a frictionless horizontal track and the system is immersed in a uniform electric field of magnitude 5×105 V/m, directed as shown in figure. If the block is released suddenly from rest when the spring is unstretched then the maximum extension in the spring is
Answer» A block of mass $4 kg$ carrying a charge $50 μ C$ is connected to a spring for which spring constant is $100 N/m$ . The block lies on a frictionless horizontal track and the system is immersed in a uniform electric field of magnitude $5 \times 10^{5} V/m$ , directed as shown in figure. If the block is released suddenly from rest when the spring is unstretched then the maximum extension in the spring is

Discussion

3133.	39.A stone is dropped into a quite lake and waves motion in circles at speed of 5 cm/s at the instant when the radius of the circular wave is 8cm .how fast is the enclosed area increasing
Answer» 39.A stone is dropped into a quite lake and waves motion in circles at speed of 5 cm/s at the instant when the radius of the circular wave is 8cm .how fast is the enclosed area increasing

Discussion

3134.	The time taken by the galvanic cell which operates almost ideally under reversible conditions at a current of 1016 A to deliver 1 mole of electron is (1) 19.30×1020 s (2) 4.825 × 1020 s (3) 9.65× 1020s (4) 3.4×10*11 s
Answer» The time taken by the galvanic cell which operates almost ideally under reversible conditions at a current of 1016 A to deliver 1 mole of electron is (1) 19.30×1020 s (2) 4.825 × 1020 s (3) 9.65× 1020s (4) 3.4×10*11 s

Discussion

3135.	A point object is placed at a distance 5R3 from the pole of a concave mirror. The radius of curvature of the mirror is R. The point object oscillates with an amplitude of 1 mm perpendicular to the principal axis. Then, the amplitude of oscillation of the image is
Answer» A point object is placed at a distance $\frac{5 R}{3}$ from the pole of a concave mirror. The radius of curvature of the mirror is $R$ . The point object oscillates with an amplitude of $1 mm$ perpendicular to the principal axis. Then, the amplitude of oscillation of the image is

Discussion

3136.	The cathode of a photoelectric cell is changed such that the work function changes from W1 to W2 (W2>W1). If the current before and after change are l1 and l2 all other conditions remaining unchanged, then (assuming hn > W2)
Answer» The cathode of a photoelectric cell is changed such that the work function changes from $W_{1} t o W_{2} (W_{2} > W_{1})$ . If the current before and after change are $l_{1} a n d l_{2}$ all other conditions remaining unchanged, then (assuming hn > $W_{2}$ )

Discussion

3137.	The I-V characteristic curve of an LED is
Answer» The I-V characteristic curve of an LED is

Discussion

3138.	A ball is thrown vertically upward. What is the magnitude of velocity at the highest point?
Answer» A ball is thrown vertically upward. What is the magnitude of velocity at the highest point?

Discussion

3139.	The dimensional formula of the magnetic field (B) is -
Answer» The dimensional formula of the magnetic field $(B)$ is -

Discussion

3140.	ntFind critical points and find maximum and minimum valuen ntn ntf(x)=a/x+b/(a-x)n
Answer» ntFind critical points and find maximum and minimum valuen ntn ntf(x)=a/x+b/(a-x)n

Discussion

3141.	A small spherical steel ball is placed a little away from the centre of a large concave mirror of radius of curvature R = 2.5 m. The ball is then released. What is the time period of the motion? Neglect friction and take g = 10ms−2
Answer» A small spherical steel ball is placed a little away from the centre of a large concave mirror of radius of curvature R = 2.5 m. The ball is then released. What is the time period of the motion? Neglect friction and take g = $10 m s^{- 2}$

Discussion

3142.	At what temperature is the average velocity of O2 molecule equal to the root mean square velocity at 27∘ C?
Answer» At what temperature is the average velocity of $O_{2}$ molecule equal to the root mean square velocity at $27^{\circ} C$ ?

Discussion

3143.	The ratio of contributions made by the electric field and magnetic field components to the intensity of an EM wave is,
Answer» The ratio of contributions made by the electric field and magnetic field components to the intensity of an $E M$ wave is,

Discussion

3144.	Dielectrics do not conduct electricity under normal conditions because
Answer» Dielectrics do not conduct electricity under normal conditions because

Discussion

3145.	The kinetic energy of an electron in the second Bohr orbit of a hydrogen atom is equal to h2xma20. The value of 10x is .(a0 is radius of Bohr's orbit) (Nearest integer)[Given: π=3.14]
Answer» The kinetic energy of an electron in the second Bohr orbit of a hydrogen atom is equal to $\frac{h^{2}}{x m a_{0}^{2}}$ . The value of 10x is . ( $a_{0}$ is radius of Bohr's orbit) (Nearest integer) [Given: $π = 3.14$ ]

Discussion

3146.	A ray of light is sent along the line which passes through the point (2, 3). The ray is reflected from the point P on xaxis. If the reflected ray passes through the point (6,4), then the co-ordinates of P are
Answer» A ray of light is sent along the line which passes through the point (2, 3). The ray is reflected from the point P on xaxis. If the reflected ray passes through the point (6,4), then the co-ordinates of P are

Discussion

3147.	An ice cream has a marked value of 700 kcal. How many kilowatt hour of energy will it deliver to the body as it is digested
Answer» An ice cream has a marked value of 700 kcal. How many kilowatt hour of energy will it deliver to the body as it is digested

Discussion

3148.	if an object of mass m has velocity v , then the dimensions of mv2 is same as that of
Answer» if an object of mass m has velocity v , then the dimensions of mv2 is same as that of

Discussion

3149.	A shell acquires the initial velocity v = 320 m/s, having made n = 2.0 turns inside the barrel whose length is equal to l = 2.0 m. Assuming that the shell moves inside the barrel with a uniform acceleration, find the angular velocity of its axial rotation at the moment when the shell escapes the barrel.
Answer» A shell acquires the initial velocity $v$ = 320 m/s, having made $n$ = 2.0 turns inside the barrel whose length is equal to $l$ = 2.0 m. Assuming that the shell moves inside the barrel with a uniform acceleration, find the angular velocity of its axial rotation at the moment when the shell escapes the barrel.

Discussion

3150.	In an experiment on photoelectric emission from a metallic surface, wavelength of incident light is 2×10−7 m and stopping potential is 2.5 V. The threshold frequency of the metal is approximately (Change of electron e=1.6×10−19 C, Planck's constant h=6.6×10−34 Js)
Answer» In an experiment on photoelectric emission from a metallic surface, wavelength of incident light is $2 \times 10^{- 7} m$ and stopping potential is $2.5 V$ . The threshold frequency of the metal is approximately (Change of electron $e = 1.6 \times 10^{- 19} C,$ Planck's constant $h = 6.6 \times 10^{- 34} J s)$

Discussion

Explore topic-wise InterviewSolutions in .

Why the zero between two nonzero numbers(such as 2018) is significant?

Which one of the following pattern of electrostatic lines of force is not possible?

How do you know that the distance between centre of mass and the centre of the circle is 2rπ

If speed of light (C),force(F),kinetic energy(K) are taken as fundamental units then dimension of mass will be

the ground state energy of hydrogen atom id -13.6 eV when its e is in first excited state its excitation energy i

A mass m is suspended from the two coupled springs connected in series. The force constant for springs are K1 and K2. The time period of the suspended mass will be

The cut off wavelength of continuous X-ray from two Coolidge tubes operating at 30 kV but using different target materials (molybdenum Z= 42 and tungsten Z = 74) are

15.Radius of He nucleus is 3 fermi. The radius of 16 S 32 nucleus will be

Two thin charged metal plates are kept close to each other parallely. if the surface charge densities of each plant on their surface is 2.65 * 10-10 c/m2and -2.65* 10-10c/m2 respectively then the net electric field in between the nearly plates is ?

Derivation of expression for minimum value of coefficient of friction for body to roll without slipping.

Two blocks of masses 2kg and 4 kg are hanging with the help of massless string passing over an ideal pulley inside an elevator. The elevator is moving upward with an acceleration of g/2.the tension in the string connected between the two blocks will be.

Two particles each of mass M are connected at the two ends of a spring of force constant K . The whole system lie on a smooth horizontal plane . If the particles are pushed to compressed the spring and then released ,then frequency of oscillation is?

A vessel containing water has a constant acceleration of 19.6 m/s2 along horizontal direction. The free surface of water will be inclined with the horizontal at an angle of : [Take g=9.8 m/s2]

A body is thrown with velocity 20 m/s at an angle of 60o with the horizontal. The time gap (in s) between the two positions of body where velocity of body makes an angle of 30o with horizontal is

If a function is given as y=ln(sinx), then the first derivative of y w.r.t. x will be

60% of given sample of oxygen gas when raised to a high temperature dissociates into atoms.Ratio of its initial heat capacity(at const. vol.) to the final heat capacity(at const. vol.) will be-1)8/7, 2)25/26, 3)10/7,4)25/27

A particle of mass 10 kg is dropped from tower of height 10 m. Find the ratio of workdone by gravity from point ′A′ to ′B′ and change in potential energy from ′A′ to ′B′

Four blocks are arranged on a smooth horizontal surface as shown in the figure. The maximum value of horizontal force F, applied to one of the bottom blocks that makes all four blocks move with the same acceleration, is -

an object is thrown up with speed 49 m/s. At what ins†an ts is it 19.6 m below the highest point

One light year is approximately equal to

An object is placed at a distance 2f from the pole of a convex mirror of focal length f. Themagnification is

A ray of light going from denser to rarer medium suffers refraction at a concave surface. Which of the following relations is correct?

Out of the following which one is independent of the other two?? wave velocity frequency wavelength

A photon in motion has a mass

39.A stone is dropped into a quite lake and waves motion in circles at speed of 5 cm/s at the instant when the radius of the circular wave is 8cm .how fast is the enclosed area increasing

The time taken by the galvanic cell which operates almost ideally under reversible conditions at a current of 10*16 A to deliver 1 mole of electron is (1) 19.30×10*20 s (2) 4.825 × 10*20 s (3) 9.65× 10*20s (4) 3.4×10*11 s

A point object is placed at a distance 5R3 from the pole of a concave mirror. The radius of curvature of the mirror is R. The point object oscillates with an amplitude of 1 mm perpendicular to the principal axis. Then, the amplitude of oscillation of the image is

The cathode of a photoelectric cell is changed such that the work function changes from W1 to W2 (W2&gt;W1). If the current before and after change are l1 and l2 all other conditions remaining unchanged, then (assuming hn &gt; W2)

The I-V characteristic curve of an LED is

A ball is thrown vertically upward. What is the magnitude of velocity at the highest point?

The dimensional formula of the magnetic field (B) is -

ntFind critical points and find maximum and minimum valuen ntn ntf(x)=a/x+b/(a-x)n

A small spherical steel ball is placed a little away from the centre of a large concave mirror of radius of curvature R = 2.5 m. The ball is then released. What is the time period of the motion? Neglect friction and take g = 10ms−2

At what temperature is the average velocity of O2 molecule equal to the root mean square velocity at 27∘ C?

The ratio of contributions made by the electric field and magnetic field components to the intensity of an EM wave is,

Dielectrics do not conduct electricity under normal conditions because

The kinetic energy of an electron in the second Bohr orbit of a hydrogen atom is equal to h2xma20. The value of 10x is .(a0 is radius of Bohr's orbit) (Nearest integer)[Given: π=3.14]

A ray of light is sent along the line which passes through the point (2, 3). The ray is reflected from the point P on xaxis. If the reflected ray passes through the point (6,4), then the co-ordinates of P are

An ice cream has a marked value of 700 kcal. How many kilowatt hour of energy will it deliver to the body as it is digested

if an object of mass m has velocity v , then the dimensions of mv2 is same as that of

In an experiment on photoelectric emission from a metallic surface, wavelength of incident light is 2×10−7 m and stopping potential is 2.5 V. The threshold frequency of the metal is approximately (Change of electron e=1.6×10−19 C, Planck's constant h=6.6×10−34 Js)

The time taken by the galvanic cell which operates almost ideally under reversible conditions at a current of 1016 A to deliver 1 mole of electron is (1) 19.30×1020 s (2) 4.825 × 1020 s (3) 9.65× 1020s (4) 3.4×10*11 s

The cathode of a photoelectric cell is changed such that the work function changes from W1 to W2 (W2>W1). If the current before and after change are l1 and l2 all other conditions remaining unchanged, then (assuming hn > W2)