50278 + Interview Questions in Physics

1.	A rod of length 6 m is placed along the x− axis between x=0 and x=6 m. The linear density (mass/length) λ of the rod varies with the distance x from the origin as λ=k(10−x). Here k is a positive constant. Find the position of the centre of mass of this rod.
Answer» A rod of length $6 m$ is placed along the $x -$ axis between $x = 0$ and $x = 6 m$ . The linear density (mass/length) $λ$ of the rod varies with the distance $x$ from the origin as $λ = k (10 - x)$ . Here $k$ is a positive constant. Find the position of the centre of mass of this rod.

Discussion

2.	A block of mass 25 kg is raised by a 50 kg man in two different ways as shown in Fig. 5.19. What is the action on the floor by the man in the two cases ? If the floor yields to a normal force of 700 N, which mode should the man adopt to lift the block without the floor yielding ?
Answer» A block of mass 25 kg is raised by a 50 kg man in two different ways as shown in Fig. 5.19. What is the action on the floor by the man in the two cases ? If the floor yields to a normal force of 700 N, which mode should the man adopt to lift the block without the floor yielding ?

Discussion

3.	When α and β rays are subjected to a magnetic fieldwhich is perpendicular to the direction of their motion, with their same speed. The curvature of path of both the particle are:- (1) equal (2) more for α particles (3) more for β particles (4) none
Answer» When α and β rays are subjected to a magnetic fieldwhich is perpendicular to the direction of their motion, with their same speed. The curvature of path of both the particle are:- (1) equal (2) more for α particles (3) more for β particles (4) none

Discussion

4.	a.what is the total charge on 75kg of electrons? b. An electron falls through a dis†an ce of 1.5 cm in a uniform electric field of magnitude2 ×10^4N/C .Now the direction of field is reversed keeping the magnitude unchanged and a proton falls through the same dis†an cecompute the time of fall in each cade neglecting gravity
Answer» a.what is the total charge on 75kg of electrons? b. An electron falls through a dis†an ce of 1.5 cm in a uniform electric field of magnitude2 ×10^4N/C .Now the direction of field is reversed keeping the magnitude unchanged and a proton falls through the same dis†an cecompute the time of fall in each cade neglecting gravity

Discussion

5.	There is hole of area a at the bottom of a cylindrical container of cross-sectional area A. Water is filled upto a height of H and all the water flows out in time t. If water is filled upto a height of 4H, all the water will flow out in time -
Answer» There is hole of area $a$ at the bottom of a cylindrical container of cross-sectional area $A$ . Water is filled upto a height of $H$ and all the water flows out in time $t$ . If water is filled upto a height of $4 H$ , all the water will flow out in time -

Discussion

6.	A galvanometer gives full scale deflection of 1 volt when acting like a voltmeter when connected in series with 2 kΩ resistance. The same galvanometer gives 500 mA full scale deflection when acting like a ammeter when connected with shunt resistance of value 0.2 Ω in parallel. Find out the resistance of galvanometer (in Ω).
Answer» A galvanometer gives full scale deflection of $1 volt$ when acting like a voltmeter when connected in series with $2 k$ $Ω$ resistance. The same galvanometer gives $500 mA$ full scale deflection when acting like a ammeter when connected with shunt resistance of value $0.2 Ω$ in parallel. Find out the resistance of galvanometer (in $Ω$ ).

Discussion

7.	A lake is covered with ice and the atmospheric temperature above the ice is −20∘C. Find the rate of formation of ice (in cm/hr) when its thickness is 10 cm.[Thermal conductivity of ice =0.005 cgs units, density of ice =0.9 g/cc and latent heat of fusion of ice =80 cal/g].
Answer» A lake is covered with ice and the atmospheric temperature above the ice is $- 20^{\circ} C$ . Find the rate of formation of ice $(in cm/hr)$ when its thickness is $10 cm$ . [Thermal conductivity of ice $= 0.005 cgs$ units, density of ice $= 0.9 g/cc$ and latent heat of fusion of ice $= 80 cal/g$ ].

Discussion

8.	Which of the following is zero for an isochoric process?
Answer» Which of the following is zero for an isochoric process?

Discussion

9.	A bullet of mass 4 g when fired with a velocity of 50 m/s, can enter a wall up to a depth of 10 cm. How much will be the average resistance offered by the wall?
Answer» A bullet of mass 4 g when fired with a velocity of 50 m/s, can enter a wall up to a depth of 10 cm. How much will be the average resistance offered by the wall?

Discussion

10.	A U-tube contains water and oil separated by mercury. The mercury columns in the two arms are at the same level with 10 cm of water in one arm and 12.5 cm of oil in the other, as shown in the figure. What is the relative density of oil?
Answer» A U-tube contains water and oil separated by mercury. The mercury columns in the two arms are at the same level with 10 cm of water in one arm and 12.5 cm of oil in the other, as shown in the figure. What is the relative density of oil?

Discussion

11.	The position of a body moving along x axis at time t is given by -2t2 + t + 2 what is the average velocity of the body between t = 0 sec to t= 5 sec and instantaneous velocity of the body at t=5 seconds
Answer» The position of a body moving along x axis at time t is given by -2t2 + t + 2 what is the average velocity of the body between t = 0 sec to t= 5 sec and instantaneous velocity of the body at t=5 seconds

Discussion

12.	Consider two solid uniform spherical objects of the same density ρ. One has radius R and the other has radius 2R. They are in outer space where the gravitational fields from other objects are negligible. If they are arranged with their surfaces touching, what is the contact force between the objects due to their gravitational attraction?
Answer» Consider two solid uniform spherical objects of the same density $ρ$ . One has radius $R$ and the other has radius $2 R$ . They are in outer space where the gravitational fields from other objects are negligible. If they are arranged with their surfaces touching, what is the contact force between the objects due to their gravitational attraction?

Discussion

13.	If the temperature of a uniform steel rod of mass 12 kg and length 1 m is increased by 20 ∘C, its moment of inertia about its perpendicular bisector increases by -[ α=11×10−6/ ∘C ]
Answer» If the temperature of a uniform steel rod of mass $12 kg$ and length $1 m$ is increased by $20^{\circ} C$ , its moment of inertia about its perpendicular bisector increases by - $[α = 11 \times 10^{- 6} /^{\circ} C]$

Discussion

14.	A body of mass 'm' is moving in a straight line at a constant speed 'v'. Its kinetic energy is 'k' and the magnitude of its momentum is 'p'. Which of the following relations is/are correct?
Answer» A body of mass 'm' is moving in a straight line at a constant speed 'v'. Its kinetic energy is 'k' and the magnitude of its momentum is 'p'. Which of the following relations is/are correct?

Discussion

15.	A heavy solid sphere is thrown on a horizontal rough surface with initial velocity u without rolling. What will be its speed when it starts pure rolling? (Assume u=7 m/s)
Answer» A heavy solid sphere is thrown on a horizontal rough surface with initial velocity $u$ without rolling. What will be its speed when it starts pure rolling? (Assume $u = 7 m/s$ )

Discussion

16.	46. Atmospheric air has 78% N2. 21% O2 0. 9%Ar 0. 1%CO2 by volume.What is the molecular mass of air in the atmosphere
Answer» 46. Atmospheric air has 78% N2. 21% O2 0. 9%Ar 0. 1%CO2 by volume.What is the molecular mass of air in the atmosphere

Discussion

17.	The equivalent inductance between points P and Q is
Answer» The equivalent inductance between points $P$ and $Q$ is

Discussion

18.	Aninfinite line charge produces a field of 9 × 104N/C at a distance of 2 cm. Calculate the linear charge density.
Answer» An infinite line charge produces a field of 9 × 10⁴ N/C at a distance of 2 cm. Calculate the linear charge density.

Discussion

19.	A body started with velocity of 20 ms−1 and moving with an acceleration of 2 ms−2. The distance travelled by the body in the 8th second is
Answer» A body started with velocity of $20 {ms}^{- 1}$ and moving with an acceleration of $2 {ms}^{- 2}$ . The distance travelled by the body in the $8^{t h}$ second is

Discussion

20.	A series LCR circuit connected across (200 V,60 Hz) source. It consists of a capacitor of capacitive reactance 30 Ω, a non-inductive resistor of 40 Ω and an ideal inductor of inductive reactance 90 Ω as shown in the figure. The potential difference across the resistor will be nearly -[0.77 Mark]
Answer» A series $LCR$ circuit connected across $(200 V, 60 Hz)$ source. It consists of a capacitor of capacitive reactance $30 Ω$ , a non-inductive resistor of $40 Ω$ and an ideal inductor of inductive reactance $90 Ω$ as shown in the figure. The potential difference across the resistor will be nearly - $[$ 0.77 Mark $]$

Discussion

21.	Define the current sensitivity of a galvanometer. Write its S. I. unit. Figure shows two circuits each having a galvanometer and a battery of 3V. When the galvanometers in each arrangement do not show any deflection, obtain the ratio R1R2.
Answer» Define the current sensitivity of a galvanometer. Write its S. I. unit. Figure shows two circuits each having a galvanometer and a battery of $3 V$ . When the galvanometers in each arrangement do not show any deflection, obtain the ratio $\frac{R_{1}}{R_{2}}$ .

Discussion

22.	A ray parallel to the x - axis is incident at a point P on a parabolic reflecting surface, and the reflected ray becomes parallel to y - axis as shown in the figure. If the equation of parabola is given by y2−2x=0 , then the coordinates of point P are
Answer» A ray parallel to the x - axis is incident at a point $P$ on a parabolic reflecting surface, and the reflected ray becomes parallel to y - axis as shown in the figure. If the equation of parabola is given by $y^{2} - 2 x = 0$ , then the coordinates of point $P$ are

Discussion

23.	When a p-n diode is reverse biased, then
Answer» When a p-n diode is reverse biased, then

Discussion

24.	A virtual erect image by a diverging lens is represented by(u,v,f are coordinates)
Answer» A virtual erect image by a diverging lens is represented by ( $u, v, f$ are coordinates)

Discussion

25.	Two particles A and B are moving on two concentric circles of radii R1 and R2 with equal angular speed ω. At t=0, their positions and direction of motion are shown in the figure :The relative velocity −→vA−−→vB at t=π2ω is given by :
Answer» Two particles $A$ and $B$ are moving on two concentric circles of radii $R_{1} and R_{2}$ with equal angular speed $ω$ . At $t = 0$ , their positions and direction of motion are shown in the figure : The relative velocity $_{A} -_{B} at t = \frac{π}{2 ω}$ is given by :

Discussion

26.	A brass wire 1.8 m long at 27 °C is held taut with little tension between two rigid supports. If the wire is cooled to a temperature of –39 °C, what is the tension developed in the wire, if its diameter is 2.0 mm ? Co-efficient of linear expansion of brass = 2.0 × 10¯⁵ K¯¹; Young’s modulus of brass = 0.91 × 10¹¹ Pa.
Answer» A brass wire 1.8 m long at 27 °C is held taut with little tension between two rigid supports. If the wire is cooled to a temperature of –39 °C, what is the tension developed in the wire, if its diameter is 2.0 mm ? Co-efficient of linear expansion of brass = 2.0 × 10¯⁵ K¯¹; Young’s modulus of brass = 0.91 × 10¹¹ Pa.

Discussion

27.	A small stone tied to a 28cm long thread is whirled in a horizontal circle at 10 revolution in 5 seconds. find its angular and linear velocitiest
Answer» A small stone tied to a 28cm long thread is whirled in a horizontal circle at 10 revolution in 5 seconds. find its angular and linear velocitiest

Discussion

28.	Figure shows a large conducting ceiling having uniform charge density σ below which a charge particle of charge q0 and mass m is hung from point O, through a small string of length L. Calculate the minimum horizontal velocity v required for the string to become horizontal.
Answer» Figure shows a large conducting ceiling having uniform charge density $σ$ below which a charge particle of charge $q_{0}$ and mass m is hung from point O, through a small string of length $L$ . Calculate the minimum horizontal velocity v required for the string to become horizontal.

Discussion

29.	Two light waves having the same wavelength (λ) in vacuum are in phase initially. Then, the first ray travels path length L1 through a medium of refractive index μ1. The second ray travels a path of length L2 through a medium of refractive index μ2. The two waves are then combined to observe interference effects. The phase difference between the two, when they interfere-
Answer» Two light waves having the same wavelength $(λ)$ in vacuum are in phase initially. Then, the first ray travels path length $L_{1}$ through a medium of refractive index $μ_{1}$ . The second ray travels a path of length $L_{2}$ through a medium of refractive index $μ_{2}$ . The two waves are then combined to observe interference effects. The phase difference between the two, when they interfere-

Discussion

30.	Find the moment of inertia of a solid cylinder of length l, radius R, about the central axis parallel to the height of the cylinder. The density of the cylinder varies with radius as ρ=2r.
Answer» Find the moment of inertia of a solid cylinder of length $l$ , radius $R$ , about the central axis parallel to the height of the cylinder. The density of the cylinder varies with radius as $ρ = 2 r$ .

Discussion

31.	A circuit A takes a current of 3 A at a power factor of 0.6 lagging when connected to a 115 V, 50 Hz supply. Another circuit B takes a current of 5 A at a power factor of 0.707 leading when connected to the same supply. If the two circuits are connected in series across a 230 V, 50 Hz supply. Calculate the power consumed in the circuit.
Answer» A circuit $A$ takes a current of $3 A$ at a power factor of $0.6$ lagging when connected to a $115 V, 50 Hz$ supply. Another circuit $B$ takes a current of $5 A$ at a power factor of $0.707$ leading when connected to the same supply. If the two circuits are connected in series across a $230 V, 50 Hz$ supply. Calculate the power consumed in the circuit.

Discussion

32.	The figure shows the stress-strain plot for an aluminium wire, which is stretched by a machine pulling in opposite directions at the ends of the wire. The wire has an initial length of 0.8 m and initial cross-sectional area of 2.0×10−6 m2. How much work is done by the machine on the wire to produce a strain of 1.0×10−3 ?
Answer» The figure shows the stress-strain plot for an aluminium wire, which is stretched by a machine pulling in opposite directions at the ends of the wire. The wire has an initial length of $0.8 m$ and initial cross-sectional area of $2.0 \times 10^{- 6} m^{2}$ . How much work is done by the machine on the wire to produce a strain of $1.0 \times 10^{- 3}$ $?$

Discussion

33.	Difference between electric field and magnetic field
Answer» Difference between electric field and magnetic field

Discussion

34.	Figure shows a man standing stationary with respect to a horizontal conveyor belt. If the coefficient of static friction between the man's shoes and the belt is 0.2, up to what acceleration of the belt can the man continue to be stationary relative to the belt? (Mass of the man = 65 kg). ___
Answer» Figure shows a man standing stationary with respect to a horizontal conveyor belt. If the coefficient of static friction between the man's shoes and the belt is 0.2, up to what acceleration of the belt can the man continue to be stationary relative to the belt? (Mass of the man = 65 kg). ___

34.

Figure shows a man standing stationary with respect to a horizontal conveyor belt. If the coefficient of static friction between the man's shoes and the belt is 0.2, up to what acceleration of the belt can the man continue to be stationary relative to the belt? (Mass of the man = 65 kg). ___

Answer»

Figure shows a man standing stationary with respect to a horizontal conveyor belt. If the coefficient of static friction between the man's shoes and the belt is 0.2, up to what acceleration of the belt can the man continue to be stationary relative to the belt? (Mass of the man = 65 kg).

___

Discussion

35.	The period of oscillation of a simple pendulum is given by the relation T = 2 pie root under L/g. The measured value of length London and the period of oscillations for 50 oscillations are (20.0 +- 0.1)cm and (45+-1) sec respectively. Find the absolute error in determination of g.
Answer» The period of oscillation of a simple pendulum is given by the relation T = 2 pie root under L/g. The measured value of length London and the period of oscillations for 50 oscillations are (20.0 +- 0.1)cm and (45+-1) sec respectively. Find the absolute error in determination of g.

Discussion

36.	Three identical particles each of mass 1 kg are placed with their centres on a straight line. Their centres are marked at A,B andC respectively. All the centres A,B and C are placed at equal distance of 2 m. Find the distance of centre of mass of system from A
Answer» Three identical particles each of mass $1 kg$ are placed with their centres on a straight line. Their centres are marked at $A, B$ and $C$ respectively. All the centres $A, B$ and $C$ are placed at equal distance of $2 m$ . Find the distance of centre of mass of system from $A$

Discussion

37.	33.What is the distribution of charge body diagonally in a cube of Capacitance C placed on each edge of the cube How to know that the how much charge will flow from each edge?
Answer» 33.What is the distribution of charge body diagonally in a cube of Capacitance C placed on each edge of the cube How to know that the how much charge will flow from each edge?

Discussion

38.	Time required to boil 2 litres of water initially at20°C by a heater coil which works at 80%efficiency spending 500 joule/s is(a) 82 minutes (b) 50 minutes(c) 28 minutes (d) 37 minutes
Answer» Time required to boil 2 litres of water initially at 20°C by a heater coil which works at 80% efficiency spending 500 joule/s is (a) 82 minutes (b) 50 minutes (c) 28 minutes (d) 37 minutes

Discussion

39.	Hoop tension in a pressure pipe (where 'p' is the pressure at the pipe centre, 'd' is the diameter of pipe and 't' is the thickness of pipe wall) is given by
Answer» Hoop tension in a pressure pipe (where 'p' is the pressure at the pipe centre, 'd' is the diameter of pipe and 't' is the thickness of pipe wall) is given by

Discussion

40.	In a YDSE experiment using monochromatic light, a mica sheet of refractive index 1.6 and thickness 1.964 micron is introduced in the path of one of the interfering waves. The mica sheet is then removed and the distance between slits and screen is doubled. It is found that the distance between successive maxima or minima now is the same as the observed fringe shift on introduction of mica sheet. The wavelength of light used is
Answer» In a $Y D S E$ experiment using monochromatic light, a mica sheet of refractive index $1.6$ and thickness $1.964 micron$ is introduced in the path of one of the interfering waves. The mica sheet is then removed and the distance between slits and screen is doubled. It is found that the distance between successive maxima or minima now is the same as the observed fringe shift on introduction of mica sheet. The wavelength of light used is

Discussion

41.	Two moving particles P and Q are 10 m apart at a certain instant. The velocity of P is 8 m/s making an angle of 30∘ with the line joining P and Q. The velocity of Q is 6 m/s making an angle of 30∘ with the line joining P and Q as shown in figure. The angular velocity of P with respect to Q is
Answer» Two moving particles $P$ and $Q$ are $10 m$ apart at a certain instant. The velocity of $P$ is $8 m/s$ making an angle of $30^{\circ}$ with the line joining $P$ and $Q$ . The velocity of $Q$ is $6 m/s$ making an angle of $30^{\circ}$ with the line joining $P$ and $Q$ as shown in figure. The angular velocity of $P$ with respect to $Q$ is

Discussion

42.	What does relative motion mean?
Answer» What does relative motion mean?

Discussion

43.	If we charge a human body,will there be any attraction or replulsion with another human body?
Answer» If we charge a human body,will there be any attraction or replulsion with another human body?

Discussion

44.	A force →F=(a^i+b^j)N acts on a body which displaces it by →s=(c^i+d^j)m. The work done by the force is
Answer» A force $\to F = (a^i + b^j) N$ acts on a body which displaces it by $\to s = (c^i + d^j) m$ . The work done by the force is

Discussion

45.	Two plane mirrors are inclined at an angleof 60 degree . if a light ray is incidet horizntally on 1st mirror and reflecte by2 nd mirror find the angle of deviation
Answer» Two plane mirrors are inclined at an angleof 60 degree . if a light ray is incidet horizntally on 1st mirror and reflecte by2 nd mirror find the angle of deviation

Discussion

46.	In the network of resistors shown in the figure, the equivalent resistance between A and B is
Answer» In the network of resistors shown in the figure, the equivalent resistance between $A$ and $B$ is

Discussion

47.	A thin conducting ring of radius R is given a charge +Q. The electric field at the centre O of the ring due to thecharge on the part AKB of the ring is E. The electric field at the centre due to the charge on the part ACDB ofthe ring is
Answer» A thin conducting ring of radius R is given a charge +Q. The electric field at the centre O of the ring due to the charge on the part AKB of the ring is E. The electric field at the centre due to the charge on the part ACDB of the ring is

Discussion

48.	To establish an instantaneous displacement current of magnitude i A in between the plates of a parallel plate capacitor of capacitance 12 F, the value of dVdt is
Answer» To establish an instantaneous displacement current of magnitude $i A$ in between the plates of a parallel plate capacitor of capacitance $\frac{1}{2} F$ , the value of $\frac{d V}{d t}$ is

Discussion

49.	A ball is thrown vertically upwards. Which of the given graphs are correct? v, h and t represent velocity, height from ground, and time respectively.
Answer» A ball is thrown vertically upwards. Which of the given graphs are correct? v, h and t represent velocity, height from ground, and time respectively.

Discussion

50.	Two charges 5 × 10–8 C and –3 × 10–8 C are located 16 cm apart. At what point(s) on the line joining the two charges is the electricpotential zero? Take the potential at infinity to be zero.
Answer» Two charges 5 × 10–8 C and –3 × 10–8 C are located 16 cm apart. At what point(s) on the line joining the two charges is the electricpotential zero? Take the potential at infinity to be zero.

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

A rod of length 6 m is placed along the x− axis between x=0 and x=6 m. The linear density (mass/length) λ of the rod varies with the distance x from the origin as λ=k(10−x). Here k is a positive constant. Find the position of the centre of mass of this rod.

A block of mass 25 kg is raised by a 50 kg man in two different ways as shown in Fig. 5.19. What is the action on the floor by the man in the two cases ? If the floor yields to a normal force of 700 N, which mode should the man adopt to lift the block without the floor yielding ?

When α and β rays are subjected to a magnetic fieldwhich is perpendicular to the direction of their motion, with their same speed. The curvature of path of both the particle are:- (1) equal (2) more for α particles (3) more for β particles (4) none

There is hole of area a at the bottom of a cylindrical container of cross-sectional area A. Water is filled upto a height of H and all the water flows out in time t. If water is filled upto a height of 4H, all the water will flow out in time -

A lake is covered with ice and the atmospheric temperature above the ice is −20∘C. Find the rate of formation of ice (in cm/hr) when its thickness is 10 cm.[Thermal conductivity of ice =0.005 cgs units, density of ice =0.9 g/cc and latent heat of fusion of ice =80 cal/g].

Which of the following is zero for an isochoric process?

A bullet of mass 4 g when fired with a velocity of 50 m/s, can enter a wall up to a depth of 10 cm. How much will be the average resistance offered by the wall?

A U-tube contains water and oil separated by mercury. The mercury columns in the two arms are at the same level with 10 cm of water in one arm and 12.5 cm of oil in the other, as shown in the figure. What is the relative density of oil?

The position of a body moving along x axis at time t is given by -2t2 + t + 2 what is the average velocity of the body between t = 0 sec to t= 5 sec and instantaneous velocity of the body at t=5 seconds

If the temperature of a uniform steel rod of mass 12 kg and length 1 m is increased by 20 ∘C, its moment of inertia about its perpendicular bisector increases by -[ α=11×10−6/ ∘C ]

A body of mass 'm' is moving in a straight line at a constant speed 'v'. Its kinetic energy is 'k' and the magnitude of its momentum is 'p'. Which of the following relations is/are correct?

A heavy solid sphere is thrown on a horizontal rough surface with initial velocity u without rolling. What will be its speed when it starts pure rolling? (Assume u=7 m/s)

46. Atmospheric air has 78% N2. 21% O2 0. 9%Ar 0. 1%CO2 by volume.What is the molecular mass of air in the atmosphere

The equivalent inductance between points P and Q is

Aninfinite line charge produces a field of 9 × 104N/C at a distance of 2 cm. Calculate the linear charge density.

A body started with velocity of 20 ms−1 and moving with an acceleration of 2 ms−2. The distance travelled by the body in the 8th second is

A series LCR circuit connected across (200 V,60 Hz) source. It consists of a capacitor of capacitive reactance 30 Ω, a non-inductive resistor of 40 Ω and an ideal inductor of inductive reactance 90 Ω as shown in the figure. The potential difference across the resistor will be nearly -[0.77 Mark]

Define the current sensitivity of a galvanometer. Write its S. I. unit. Figure shows two circuits each having a galvanometer and a battery of 3V. When the galvanometers in each arrangement do not show any deflection, obtain the ratio R1R2.

A ray parallel to the x - axis is incident at a point P on a parabolic reflecting surface, and the reflected ray becomes parallel to y - axis as shown in the figure. If the equation of parabola is given by y2−2x=0 , then the coordinates of point P are

When a p-n diode is reverse biased, then

A virtual erect image by a diverging lens is represented by(u,v,f are coordinates)

Two particles A and B are moving on two concentric circles of radii R1 and R2 with equal angular speed ω. At t=0, their positions and direction of motion are shown in the figure :The relative velocity −→vA−−→vB at t=π2ω is given by :

A small stone tied to a 28cm long thread is whirled in a horizontal circle at 10 revolution in 5 seconds. find its angular and linear velocitiest

Figure shows a large conducting ceiling having uniform charge density σ below which a charge particle of charge q0 and mass m is hung from point O, through a small string of length L. Calculate the minimum horizontal velocity v required for the string to become horizontal.

Find the moment of inertia of a solid cylinder of length l, radius R, about the central axis parallel to the height of the cylinder. The density of the cylinder varies with radius as ρ=2r.

Difference between electric field and magnetic field

Figure shows a man standing stationary with respect to a horizontal conveyor belt. If the coefficient of static friction between the man's shoes and the belt is 0.2, up to what acceleration of the belt can the man continue to be stationary relative to the belt? (Mass of the man = 65 kg). ___

The period of oscillation of a simple pendulum is given by the relation T = 2 pie root under L/g. The measured value of length London and the period of oscillations for 50 oscillations are (20.0 +- 0.1)cm and (45+-1) sec respectively. Find the absolute error in determination of g.

Three identical particles each of mass 1 kg are placed with their centres on a straight line. Their centres are marked at A,B andC respectively. All the centres A,B and C are placed at equal distance of 2 m. Find the distance of centre of mass of system from A

33.What is the distribution of charge body diagonally in a cube of Capacitance C placed on each edge of the cube How to know that the how much charge will flow from each edge?

Time required to boil 2 litres of water initially at20°C by a heater coil which works at 80%efficiency spending 500 joule/s is(a) 82 minutes (b) 50 minutes(c) 28 minutes (d) 37 minutes

Hoop tension in a pressure pipe (where 'p' is the pressure at the pipe centre, 'd' is the diameter of pipe and 't' is the thickness of pipe wall) is given by

Two moving particles P and Q are 10 m apart at a certain instant. The velocity of P is 8 m/s making an angle of 30∘ with the line joining P and Q. The velocity of Q is 6 m/s making an angle of 30∘ with the line joining P and Q as shown in figure. The angular velocity of P with respect to Q is

What does relative motion mean?

If we charge a human body,will there be any attraction or replulsion with another human body?

A force →F=(a^i+b^j)N acts on a body which displaces it by →s=(c^i+d^j)m. The work done by the force is

Two plane mirrors are inclined at an angleof 60 degree . if a light ray is incidet horizntally on 1st mirror and reflecte by2 nd mirror find the angle of deviation

In the network of resistors shown in the figure, the equivalent resistance between A and B is

A thin conducting ring of radius R is given a charge +Q. The electric field at the centre O of the ring due to thecharge on the part AKB of the ring is E. The electric field at the centre due to the charge on the part ACDB ofthe ring is

To establish an instantaneous displacement current of magnitude i A in between the plates of a parallel plate capacitor of capacitance 12 F, the value of dVdt is

A ball is thrown vertically upwards. Which of the given graphs are correct? v, h and t represent velocity, height from ground, and time respectively.

Two charges 5 × 10–8 C and –3 × 10–8 C are located 16 cm apart. At what point(s) on the line joining the two charges is the electricpotential zero? Take the potential at infinity to be zero.