50278 + Interview Questions in Physics

1.	A particle having specific charge s starts from rest in a region where the electric field has constant direction but magnitude verifying with time t as E=E0t. In time t, it is observed that the particle acquires a velocity v after covering a distance x, then
Answer» A particle having specific charge s starts from rest in a region where the electric field has constant direction but magnitude verifying with time t as $E = E_{0} t$ . In time t, it is observed that the particle acquires a velocity v after covering a distance x, then

Discussion

2.	When a metal surface is illuminated by light of wavelengths 400 nm and 250 nm the maximum velocities of the photoelectrons ejected are v and 2v respectively. The work function of the metal is (h = Planck's constant, c = velocity of light in air)
Answer» When a metal surface is illuminated by light of wavelengths 400 nm and 250 nm the maximum velocities of the photoelectrons ejected are v and 2v respectively. The work function of the metal is (h = Planck's constant, c = velocity of light in air)

Discussion

3.	a body slides down from rest from the top of 6.4m long rough plane inclined at 30degree with the horizontal find the time taken by block in reaching the bottom of the plane Take coefficient of friction to be 0.2 and g=9.8m/s^2
Answer» a body slides down from rest from the top of 6.4m long rough plane inclined at 30degree with the horizontal find the time taken by block in reaching the bottom of the plane Take coefficient of friction to be 0.2 and g=9.8m/s^2

Discussion

4.	What is the equivalent capacitance between points A and B?
Answer» What is the equivalent capacitance between points A and B?

Discussion

5.	Which of the following figure represents a convex lens?
Answer» Which of the following figure represents a convex lens?

Discussion

6.	Two masses m1 and m2 which are connected with a light string, are placed over a frictionless pulley. This set up is placed over a weighing machine, as shown. Three combination of masses m1 and m2 are used, in first case m1=6 kg and m2=2 kg, In second case m1=5 kg and m2=3kg and in third case m1=4 kg and m2=4 kg. Masses are held stationary initially and then released. If the readings of the weighing machine after the release in three cases are W1,W2 and W3 respectively then:
Answer» Two masses $m_{1} a n d m_{2}$ which are connected with a light string, are placed over a frictionless pulley. This set up is placed over a weighing machine, as shown. Three combination of masses $m_{1} a n d m_{2}$ are used, in first case $m_{1} = 6 k g a n d m_{2} = 2 k g,$ In second case $m_{1} = 5 k g a n d m_{2} = 3 k g$ and in third case $m_{1} = 4 k g a n d m_{2} = 4 k g .$ Masses are held stationary initially and then released. If the readings of the weighing machine after the release in three cases are $W_{1}, W_{2} a n d W_{3}$ respectively then:

Discussion

7.	A charged particle moves in a uniform magnetic field perpendicular to it, with a radius of curvature 4 cm. On passing through a metallic sheet, it loses half of its kinetic energy. Then, the radius of curvature of the particle is
Answer» A charged particle moves in a uniform magnetic field perpendicular to it, with a radius of curvature $4 c m$ . On passing through a metallic sheet, it loses half of its kinetic energy. Then, the radius of curvature of the particle is

Discussion

8.	The speed of projection of a projectile is increased by 5%, without changing the angle of projection. The percentage increase in the range will be
Answer» The speed of projection of a projectile is increased by 5%, without changing the angle of projection. The percentage increase in the range will be

Discussion

9.	In a photoelectric experiment for 4000∘A incident radiation, the potential difference to stop the ejection is 2 V. If the incident light is changed to 3000∘A , then the potential required to stop the ejection of electrons will be
Answer» In a photoelectric experiment for $4000 \circ A$ incident radiation, the potential difference to stop the ejection is 2 V. If the incident light is changed to $3000 \circ A$ , then the potential required to stop the ejection of electrons will be

Discussion

10.	A wire bent in the shape of a regular n polygonal loop carries a steady current I. Let l be the perpendicular distance of a given segment and R be the distance of a vertex, both from the centre of the loop. The magnitude of the magnetic field at the centre of the loop is given by.
Answer» A wire bent in the shape of a regular n polygonal loop carries a steady current I. Let l be the perpendicular distance of a given segment and R be the distance of a vertex, both from the centre of the loop. The magnitude of the magnetic field at the centre of the loop is given by.

Discussion

11.	A solid ball is falling in a liquid with terminal velocity v. The power delivered by viscous force is proportional to
Answer» A solid ball is falling in a liquid with terminal velocity $v$ . The power delivered by viscous force is proportional to

Discussion

12.	Three capacitors are connected as shown in figure. Then the charge on capacitor plate C1 is:
Answer» Three capacitors are connected as shown in figure. Then the charge on capacitor plate $C_{1}$ is:

Discussion

13.	In the circuit shown in the adjacent figure, the batteries are ideal. The charge on the capacitor C is
Answer» In the circuit shown in the adjacent figure, the batteries are ideal. The charge on the capacitor C is

13.

In the circuit shown in the adjacent figure, the batteries are ideal. The charge on the capacitor C is

Answer»

In the circuit shown in the adjacent figure, the batteries are ideal. The charge on the capacitor C is

Discussion

14.	The electric field associated with a light wave is E=E0 sin[1.57×107(x−ct)] where x is in meters & t in seconds. If this is incident on a metal surface of work function 1.1 eV, the stopping potential is approximately
Answer» The electric field associated with a light wave is $E = E_{0} s i n [1.57 \times 10^{7} (x - c t)]$ where x is in meters & t in seconds. If this is incident on a metal surface of work function 1.1 eV, the stopping potential is approximately

Discussion

15.	In the given figure radius of the conducting sphere is increasing according to the relation R = Vt. A point charge q is fixed at distance ‘a’ from centre of conducting sphere. The current flowing in the earthen conductor at the instant when R < a is :-
Answer» In the given figure radius of the conducting sphere is increasing according to the relation R = Vt. A point charge q is fixed at distance ‘a’ from centre of conducting sphere. The current flowing in the earthen conductor at the instant when R < a is :-

Discussion

16.	Kinetic energy of a moving electron is doubled by applying a potential difference of V. Its de Broglie wavelength changes by a factor of
Answer» Kinetic energy of a moving electron is doubled by applying a potential difference of V. Its de Broglie wavelength changes by a factor of

Discussion

17.	Match the difference in level and angle (θ) of line connecting O to A in Column I with the respective options in Column II. (Liquid is ideal in all cases and g=10 m/s2)
Answer» Match the difference in level and angle $(θ)$ of line connecting O to A in Column I with the respective options in Column II. (Liquid is ideal in all cases and $g = 10 m / s^{2}$ )

Discussion

18.	200 g of ice at −20∘C is mixed with 500 g of water at 20∘C in an insulating vessel. What is the final mass of water in the vessel? (Specific heat of ice =0.5 cal g−1∘C−1).
Answer» $200 g$ of ice at $- 20^{\circ} C$ is mixed with $500 g$ of water at $20^{\circ} C$ in an insulating vessel. What is the final mass of water in the vessel? (Specific heat of ice $= 0.5 {cal g}^{- 1}$ $^{\circ} C^{- 1}$ ).

Discussion

19.	Three particles of masses 2 kg, 3 kg and 5 kg are situated at the vertices of a right angled triangle ΔABC as shown in figure. Find the moment of inertia of the system about line PQ perpendicular to the BC and in the plane of ΔABC.
Answer» Three particles of masses $2 kg, 3 kg$ and $5 kg$ are situated at the vertices of a right angled triangle $Δ A B C$ as shown in figure. Find the moment of inertia of the system about line $P Q$ perpendicular to the $B C$ and in the plane of $Δ A B C$ .

Discussion

20.	A metal bar with a length of 1.50 m has density 6400 kgm3.Longitudinal sound waves take 3.90× 10−4 s to travel from one end of the bar to the other. What is Young's modulus for this metal?
Answer» A metal bar with a length of 1.50 m has density 6400 $\frac{k g}{m^{3}}$ .Longitudinal sound waves take $3.90 \times 10^{- 4}$ s to travel from one end of the bar to the other. What is Young's modulus for this metal?

Discussion

21.	Find →A×→B, if →A=3^i−^j+3^k and →B=−2^i+3^j+4^k
Answer» Find $\to A \times \to B$ , if $\to A = 3^i -^j + 3^k$ and $\to B = - 2^i + 3^j + 4^k$

Discussion

22.	Two coherent sources emit light waves which superimpose at a point where these can be expressed as E1=E0sin(ωt+π4) E2=2E0sin(ωt−π4) Here, E1 and E2 are the electric field strengths of the two waves at the given point. If I is the intensity of wave expressed by field strength E1, find the resultant intensity (in I).
Answer» Two coherent sources emit light waves which superimpose at a point where these can be expressed as $E_{1} = E_{0} sin (ω t + \frac{π}{4})$ $E_{2} = 2 E_{0} sin (ω t - \frac{π}{4})$ Here, $E_{1}$ and $E_{2}$ are the electric field strengths of the two waves at the given point. If I is the intensity of wave expressed by field strength $E_{1}$ , find the resultant intensity (in $I$ ).

Discussion

23.	One sphere collides with another sphere of same mass at rest inelastically. If the value of coefficient of restitution is 13, the ratio of their speeds after collision shall be
Answer» One sphere collides with another sphere of same mass at rest inelastically. If the value of coefficient of restitution is $\frac{1}{3}$ , the ratio of their speeds after collision shall be

Discussion

24.	A parallel-plate capacitor of area A, plate separation 𝑑, and capacitance C is filled with four dielectric material having dielectric constants k1,k2,k3 and k4 as shown in the figure. If a single dielectric material is to be used to have the same capacitance C in this capacitor, then its dielectric constant k is given by
Answer» A parallel-plate capacitor of area $A$ , plate separation 𝑑, and capacitance $C$ is filled with four dielectric material having dielectric constants $k_{1}, k_{2}, k_{3}$ and $k_{4}$ as shown in the figure. If a single dielectric material is to be used to have the same capacitance $C$ in this capacitor, then its dielectric constant $k$ is given by

Discussion

25.	A car of mass m is moving on a horizontal circular track of radius r. The time taken to finish one complete revolution is π2 s. If the velocity of the car at an instant t is given by v=5sin2t, then the magnitude of tangential acceleration of the car at the time when it finishes a quarter circle is p. The value of p2 is (No slipping between the car and track)
Answer» A car of mass $m$ is moving on a horizontal circular track of radius $r$ . The time taken to finish one complete revolution is $\frac{π}{2} s$ . If the velocity of the car at an instant $t$ is given by $v = 5 sin 2 t$ , then the magnitude of tangential acceleration of the car at the time when it finishes a quarter circle is $p$ . The value of $p^{2}$ is (No slipping between the car and track)

Discussion

26.	In the figure shown, find the value of frictional force between A & B and B and the surface respectively. Take g=10 m/s2.
Answer» In the figure shown, find the value of frictional force between $A$ & $B$ and $B$ and the surface respectively. Take $g = 10 {m/s}^{2}$ .

Discussion

27.	A cell of emf ε is connected across thick spherical shell of inner radius R1 and outer radius R2 as shown in figure. If resitivity of sphere is ρ, current through the cell is:
Answer» A cell of emf $ε$ is connected across thick spherical shell of inner radius $R_{1}$ and outer radius $R_{2}$ as shown in figure. If resitivity of sphere is $ρ$ , current through the cell is:

Discussion

28.	An ideal gas is taken through the process ABCDA as shown. Which process(s) is/are isobaric?
Answer» An ideal gas is taken through the process ABCDA as shown. Which process(s) is/are isobaric?

28.

An ideal gas is taken through the process ABCDA as shown. Which process(s) is/are isobaric?

Answer»

An ideal gas is taken through the process ABCDA as shown. Which process(s) is/are isobaric?

Discussion

29.	A person of mass 10 kg jumps from a stationary helicopter with the parachute open. As he falls through 50 m height, the gains a speed of 20 m/s. The work done by the viscous air drag is
Answer» A person of mass $10 kg$ jumps from a stationary helicopter with the parachute open. As he falls through $50 m$ height, the gains a speed of $20 m/s$ . The work done by the viscous air drag is

Discussion

30.	A point moves in a straight line under the retardation av2. If the initial velocity is u, the distance covered in 't' seconds is
Answer» A point moves in a straight line under the retardation $a v^{2}$ . If the initial velocity is $u$ , the distance covered in ' $t$ ' seconds is

Discussion

31.	Force −→F1=(2^i–3^j) N and −→F2=(−5^i+2^j) N act through the points whose position vectors are ^k and 3^k respectively. The vector sum of the torque due to these forces is
Answer» Force $_{1} = (2^i - 3^j) N$ and $_{2} = (- 5^i + 2^j) N$ act through the points whose position vectors are $^k$ and $3^k$ respectively. The vector sum of the torque due to these forces is

Discussion

32.	In the given figure, the distance (in m) travelled by the 10 kg mass after 10 s if the forces were applied simultaneously at t=0 is (all the surfaces are smooth).
Answer» In the given figure, the distance (in $m$ ) travelled by the $10 k g$ mass after $10 s$ if the forces were applied simultaneously at $t = 0$ is (all the surfaces are smooth).

Discussion

33.	Maga Ltd was manufacturing water-heater. In the first year of its operations, the revenue earned by the company was just sufficient to meet its costs. To increase the revenue, the company analysed the reasons of less revenues. After analysis, the company decided: (i) To reduce the labour cost by shifting the manufacturing unit to a backward area where labour was available at a very low rate. (ii) To start manufacturing solar water-heaters and reduce the production of electric water-heaters slowly. This will not only help in covering the risks, but also help in meeting other objectives too. (a) Identify the objectives of management discussed above. (b) State any two values which the company wanted to communicate to the society.
Answer» Maga Ltd was manufacturing water-heater. In the first year of its operations, the revenue earned by the company was just sufficient to meet its costs. To increase the revenue, the company analysed the reasons of less revenues. After analysis, the company decided: (i) To reduce the labour cost by shifting the manufacturing unit to a backward area where labour was available at a very low rate. (ii) To start manufacturing solar water-heaters and reduce the production of electric water-heaters slowly. This will not only help in covering the risks, but also help in meeting other objectives too. (a) Identify the objectives of management discussed above. (b) State any two values which the company wanted to communicate to the society.

33.

Maga Ltd was manufacturing water-heater. In the first year of its operations, the revenue earned by the company was just sufficient to meet its costs. To increase the revenue, the company analysed the reasons of less revenues. After analysis, the company decided: (i) To reduce the labour cost by shifting the manufacturing unit to a backward area where labour was available at a very low rate. (ii) To start manufacturing solar water-heaters and reduce the production of electric water-heaters slowly. This will not only help in covering the risks, but also help in meeting other objectives too. (a) Identify the objectives of management discussed above. (b) State any two values which the company wanted to communicate to the society.

Answer»

Maga Ltd was manufacturing water-heater. In the first year of its operations, the revenue earned by the company was just sufficient to meet its costs. To increase the revenue, the company analysed the reasons of less revenues. After analysis, the company decided:

(i) To reduce the labour cost by shifting the manufacturing unit to a backward area where labour was available at a very low rate.

(ii) To start manufacturing solar water-heaters and reduce the production of electric water-heaters slowly.

This will not only help in covering the risks, but also help in meeting other objectives too.

(a) Identify the objectives of management discussed above.

(b) State any two values which the company wanted to communicate to the society.

Discussion

34.	A body hangs from a spring balance supported from the from the ceiling of an elevator. If the elevator has an upward acceleration of 2.5m/s2 and the balance reads 50N,what is the true weight of the body?
Answer» $A b o d y h a n g s f r o m a s p r i n g b a l a n c e s u p p o r t e d f r o m t h e f r o m t h e c e i l i n g o f a n e l e v a t o r . I f t h e e l e v a t o r h a s a n u p w a r d a c c e l e r a t i o n o f 2.5 m / s^{2} a n d t h e b a l a n c e r e a d s 50 N, w h a t i s t h e t r u e w e i g h t o f t h e b o d y ?$

Discussion

35.	A wooden stick of length 3l is rotated about an end with constant angular velocity ω in a uniform magnetic field B perpendicular to the plane of motion. If the upper one-third of its length is coated with copper, the potential difference across the whole length of the stick is
Answer» A wooden stick of length 3l is rotated about an end with constant angular velocity $ω$ in a uniform magnetic field B perpendicular to the plane of motion. If the upper one-third of its length is coated with copper, the potential difference across the whole length of the stick is

35.

A wooden stick of length 3l is rotated about an end with constant angular velocity ω in a uniform magnetic field B perpendicular to the plane of motion. If the upper one-third of its length is coated with copper, the potential difference across the whole length of the stick is

Answer»

A wooden stick of length 3l is rotated about an end with constant angular velocity $ω$ in a uniform magnetic field B perpendicular to the plane of motion. If the upper one-third of its length is coated with copper, the potential difference across the whole length of the stick is

Discussion

36.	A dielectric slab of constant k = 3 is inserted inside gap of parallel plate capacitor of plate area L×L and separation of d at speed u. Power dissipation across resistance R is
Answer» A dielectric slab of constant k = 3 is inserted inside gap of parallel plate capacitor of plate area $L \times L$ and separation of d at speed u. Power dissipation across resistance R is

Discussion

37.	Two identical charged rings of charge Q = 1 and radius R = 0.1m are separated by a distance √3R meter, and are fixed. A point charge of charge q=1.0×10−9C and mass m = 2 kg is moved by external agent from the centre of left ring to the centre of right ring. Find the work done by an external agent in ___ joule.
Answer» Two identical charged rings of charge Q = 1 and radius R = 0.1m are separated by a distance $\sqrt{3} R$ meter, and are fixed. A point charge of charge $q = 1.0 \times 10^{- 9} C$ and mass m = 2 kg is moved by external agent from the centre of left ring to the centre of right ring. Find the work done by an external agent in ___ joule.

Discussion

38.	The displacement function S(x,t) of three sound waves 1,2 and 3 at a certain time t as marked on the curves that travel along x−axis through air. If P1,P2 and P3 represent their pressure amplitudes respectively, then the correct relation between them is:
Answer» The displacement function $S (x, t)$ of three sound waves $1, 2$ and $3$ at a certain time $t$ as marked on the curves that travel along $x - axis$ through air. If $P_{1}, P_{2} a n d P_{3}$ represent their pressure amplitudes respectively, then the correct relation between them is:

Discussion

39.	A particle is thrown at angle θ with horizontal over a triangle from one end of a horizontal base and grazing the vertex falls on the other end of the base. If α and β be the base angles, find tanα+tanβ.
Answer» A particle is thrown at angle $θ$ with horizontal over a triangle from one end of a horizontal base and grazing the vertex falls on the other end of the base. If $α$ and $β$ be the base angles, find $tan α + tan β$ .

Discussion

40.	Two forces, with equal magnitude F, act on a body and the magnitude of the resultant force is F3. The angle between the two forces is
Answer» Two forces, with equal magnitude $F$ , act on a body and the magnitude of the resultant force is $\frac{F}{3}$ . The angle between the two forces is

Discussion

41.	A body of mass 0.05 kg travelling with a velocity of 5 m/s make angle of 300 with the wall as shown. The body rebounds with the same speed making an angle of 300 with the wall. Find the contact force on the body in kN if the duration of contact is 1 ms.
Answer» A body of mass $0.05 k g$ travelling with a velocity of $5 m / s$ make angle of $30^{0}$ with the wall as shown. The body rebounds with the same speed making an angle of $30^{0}$ with the wall. Find the contact force on the body in $k N$ if the duration of contact is $1 m s$ .

Discussion

42.	In fig., AB is a potentiometer wire of length 10 m and resistance 2 Ω. With key (K) open the balancing length is 5.5 m. However, on closing key (K) the balancing length reduces to 5 m. The internal resistance of the cell (E1) is –
Answer» In fig., $A B$ is a potentiometer wire of length $10 m$ and resistance $2 Ω$ . With key $(K)$ open the balancing length is $5.5 m$ . However, on closing key $(K)$ the balancing length reduces to $5 m$ . The internal resistance of the cell $(E_{1})$ is –

Discussion

43.	A cylindrical drum of height 1 m made of a bad conductor is completely filled with water at 0∘C and is kept outside without a lid. The temperature of the surroundings is −10∘C. Calculate the time taken for the entire mass of the water to freeze. (Thermal conductivity of ice =k, latent heat of fusion Lf=L) [Neglect expansion of water on freezing, ρ = density of water]
Answer» A cylindrical drum of height $1 m$ made of a bad conductor is completely filled with water at $0^{\circ} C$ and is kept outside without a lid. The temperature of the surroundings is $- 10^{\circ} C$ . Calculate the time taken for the entire mass of the water to freeze. (Thermal conductivity of ice $= k$ , latent heat of fusion $L_{f} = L)$ [Neglect expansion of water on freezing, $ρ$ = density of water]

Discussion

44.	A body mass m is attached to the lower end of a spring whose upper end is fixed. The spring has negligible mass. When the mass m is slightly pulled down and released, it oscillates with a time period of 3 s. When the mass m is increased by 2 kg, the time period of oscillations becomes 5 s. The value of m in kg is
Answer» A body mass $m$ is attached to the lower end of a spring whose upper end is fixed. The spring has negligible mass. When the mass $m$ is slightly pulled down and released, it oscillates with a time period of $3 s$ . When the mass $m$ is increased by $2 k g$ , the time period of oscillations becomes $5 s$ . The value of $m$ in $k g$ is

Discussion

45.	A massive platform of mass M is moving horizontally with speed v = 6 ms−1. At t = 0 a body of mass m (m << M) is gently placed on the platform. If coefficient of friction between body and platform is μ = 0.3 and g = 10 m/s2, then
Answer» A massive platform of mass M is moving horizontally with speed v = 6 ms $^{- 1}$ . At t = 0 a body of mass m (m << M) is gently placed on the platform. If coefficient of friction between body and platform is $μ$ = 0.3 and g = 10 m/s $^{2}$ , then

Discussion

46.	How is the image formed in a plane mirror?
Answer» How is the image formed in a plane mirror?

Discussion

47.	In damped oscillations, if the amplitude becomes half of its maximum value in 1 s, then after 2 s amplitude will be (Ao is initial amplitude)
Answer» In damped oscillations, if the amplitude becomes half of its maximum value in $1 s$ , then after $2 s$ amplitude will be ( $A_{o}$ is initial amplitude)

Discussion

48.	The phase difference between alternating current and EMF is π/2 which of the following cannot be constituent of the circuit? A)LC B)L C)C D)RL
Answer» The phase difference between alternating current and EMF is π/2 which of the following cannot be constituent of the circuit? A)LC B)L C)C D)RL

48.

The phase difference between alternating current and EMF is π/2 which of the following cannot be constituent of the circuit? A)LC B)L C)C D)RL

Answer»

The phase difference between alternating current and EMF is π/2 which of the following cannot be constituent of the circuit?

A)LC

B)L

C)C

D)RL

Discussion

49.	In the adjacent diagram, CP represents a wavefront and AO & BP, the corresponding two rays. Find the condition on q for constructive interference at P between the ray BP and reflected ray OP
Answer» In the adjacent diagram, CP represents a wavefront and AO & BP, the corresponding two rays. Find the condition on q for constructive interference at P between the ray BP and reflected ray OP

49.

In the adjacent diagram, CP represents a wavefront and AO & BP, the corresponding two rays. Find the condition on q for constructive interference at P between the ray BP and reflected ray OP

Answer»

In the adjacent diagram, CP represents a wavefront and AO & BP, the corresponding two rays. Find the condition on q for constructive interference at P between the ray BP and reflected ray OP

Discussion

50.	A block of mass m rests on a rough horizontal surface as shown in the figure. Coefficient of friction between the block and the surface is μ. A force F=mg acting at angle θ with the vertical side of the block pulls it. In which of the following cases can the block be pulled along the surface?
Answer» A block of mass $m$ rests on a rough horizontal surface as shown in the figure. Coefficient of friction between the block and the surface is $μ$ . A force $F = m g$ acting at angle $θ$ with the vertical side of the block pulls it. In which of the following cases can the block be pulled along the surface?

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

A particle having specific charge s starts from rest in a region where the electric field has constant direction but magnitude verifying with time t as E=E0t. In time t, it is observed that the particle acquires a velocity v after covering a distance x, then

When a metal surface is illuminated by light of wavelengths 400 nm and 250 nm the maximum velocities of the photoelectrons ejected are v and 2v respectively. The work function of the metal is (h = Planck's constant, c = velocity of light in air)

a body slides down from rest from the top of 6.4m long rough plane inclined at 30degree with the horizontal find the time taken by block in reaching the bottom of the plane Take coefficient of friction to be 0.2 and g=9.8m/s^2

What is the equivalent capacitance between points A and B?

Which of the following figure represents a convex lens?

A charged particle moves in a uniform magnetic field perpendicular to it, with a radius of curvature 4 cm. On passing through a metallic sheet, it loses half of its kinetic energy. Then, the radius of curvature of the particle is

The speed of projection of a projectile is increased by 5%, without changing the angle of projection. The percentage increase in the range will be

In a photoelectric experiment for 4000∘A incident radiation, the potential difference to stop the ejection is 2 V. If the incident light is changed to 3000∘A , then the potential required to stop the ejection of electrons will be

A wire bent in the shape of a regular n polygonal loop carries a steady current I. Let l be the perpendicular distance of a given segment and R be the distance of a vertex, both from the centre of the loop. The magnitude of the magnetic field at the centre of the loop is given by.

A solid ball is falling in a liquid with terminal velocity v. The power delivered by viscous force is proportional to

Three capacitors are connected as shown in figure. Then the charge on capacitor plate C1 is:

In the circuit shown in the adjacent figure, the batteries are ideal. The charge on the capacitor C is

The electric field associated with a light wave is E=E0 sin[1.57×107(x−ct)] where x is in meters &amp; t in seconds. If this is incident on a metal surface of work function 1.1 eV, the stopping potential is approximately

In the given figure radius of the conducting sphere is increasing according to the relation R = Vt. A point charge q is fixed at distance ‘a’ from centre of conducting sphere. The current flowing in the earthen conductor at the instant when R &lt; a is :-

Kinetic energy of a moving electron is doubled by applying a potential difference of V. Its de Broglie wavelength changes by a factor of

Match the difference in level and angle (θ) of line connecting O to A in Column I with the respective options in Column II. (Liquid is ideal in all cases and g=10 m/s2)

200 g of ice at −20∘C is mixed with 500 g of water at 20∘C in an insulating vessel. What is the final mass of water in the vessel? (Specific heat of ice =0.5 cal g−1∘C−1).

Three particles of masses 2 kg, 3 kg and 5 kg are situated at the vertices of a right angled triangle ΔABC as shown in figure. Find the moment of inertia of the system about line PQ perpendicular to the BC and in the plane of ΔABC.

A metal bar with a length of 1.50 m has density 6400 kgm3.Longitudinal sound waves take 3.90× 10−4 s to travel from one end of the bar to the other. What is Young's modulus for this metal?

Find →A×→B, if →A=3^i−^j+3^k and →B=−2^i+3^j+4^k

One sphere collides with another sphere of same mass at rest inelastically. If the value of coefficient of restitution is 13, the ratio of their speeds after collision shall be

In the figure shown, find the value of frictional force between A &amp; B and B and the surface respectively. Take g=10 m/s2.

A cell of emf ε is connected across thick spherical shell of inner radius R1 and outer radius R2 as shown in figure. If resitivity of sphere is ρ, current through the cell is:

An ideal gas is taken through the process ABCDA as shown. Which process(s) is/are isobaric?

A person of mass 10 kg jumps from a stationary helicopter with the parachute open. As he falls through 50 m height, the gains a speed of 20 m/s. The work done by the viscous air drag is

A point moves in a straight line under the retardation av2. If the initial velocity is u, the distance covered in 't' seconds is

Force −→F1=(2^i–3^j) N and −→F2=(−5^i+2^j) N act through the points whose position vectors are ^k and 3^k respectively. The vector sum of the torque due to these forces is

In the given figure, the distance (in m) travelled by the 10 kg mass after 10 s if the forces were applied simultaneously at t=0 is (all the surfaces are smooth).

A body hangs from a spring balance supported from the from the ceiling of an elevator. If the elevator has an upward acceleration of 2.5m/s2 and the balance reads 50N,what is the true weight of the body?

A wooden stick of length 3l is rotated about an end with constant angular velocity ω in a uniform magnetic field B perpendicular to the plane of motion. If the upper one-third of its length is coated with copper, the potential difference across the whole length of the stick is

A dielectric slab of constant k = 3 is inserted inside gap of parallel plate capacitor of plate area L×L and separation of d at speed u. Power dissipation across resistance R is

The displacement function S(x,t) of three sound waves 1,2 and 3 at a certain time t as marked on the curves that travel along x−axis through air. If P1,P2 and P3 represent their pressure amplitudes respectively, then the correct relation between them is:

A particle is thrown at angle θ with horizontal over a triangle from one end of a horizontal base and grazing the vertex falls on the other end of the base. If α and β be the base angles, find tanα+tanβ.

Two forces, with equal magnitude F, act on a body and the magnitude of the resultant force is F3. The angle between the two forces is

A body of mass 0.05 kg travelling with a velocity of 5 m/s make angle of 300 with the wall as shown. The body rebounds with the same speed making an angle of 300 with the wall. Find the contact force on the body in kN if the duration of contact is 1 ms.

In fig., AB is a potentiometer wire of length 10 m and resistance 2 Ω. With key (K) open the balancing length is 5.5 m. However, on closing key (K) the balancing length reduces to 5 m. The internal resistance of the cell (E1) is –

A massive platform of mass M is moving horizontally with speed v = 6 ms−1. At t = 0 a body of mass m (m &lt;&lt; M) is gently placed on the platform. If coefficient of friction between body and platform is μ = 0.3 and g = 10 m/s2, then

How is the image formed in a plane mirror?

In damped oscillations, if the amplitude becomes half of its maximum value in 1 s, then after 2 s amplitude will be (Ao is initial amplitude)

The phase difference between alternating current and EMF is π/2 which of the following cannot be constituent of the circuit? A)LC B)L C)C D)RL

In the adjacent diagram, CP represents a wavefront and AO &amp; BP, the corresponding two rays. Find the condition on q for constructive interference at P between the ray BP and reflected ray OP

A block of mass m rests on a rough horizontal surface as shown in the figure. Coefficient of friction between the block and the surface is μ. A force F=mg acting at angle θ with the vertical side of the block pulls it. In which of the following cases can the block be pulled along the surface?

The electric field associated with a light wave is E=E0 sin[1.57×107(x−ct)] where x is in meters & t in seconds. If this is incident on a metal surface of work function 1.1 eV, the stopping potential is approximately

In the given figure radius of the conducting sphere is increasing according to the relation R = Vt. A point charge q is fixed at distance ‘a’ from centre of conducting sphere. The current flowing in the earthen conductor at the instant when R < a is :-

In the figure shown, find the value of frictional force between A & B and B and the surface respectively. Take g=10 m/s2.

A massive platform of mass M is moving horizontally with speed v = 6 ms−1. At t = 0 a body of mass m (m << M) is gently placed on the platform. If coefficient of friction between body and platform is μ = 0.3 and g = 10 m/s2, then

In the adjacent diagram, CP represents a wavefront and AO & BP, the corresponding two rays. Find the condition on q for constructive interference at P between the ray BP and reflected ray OP