40048 + Interview Questions in Physics in Class 11

1.	In the equation of motion of waves in x-direction is given by y= 10^(-4) sin(600t-2x+(pi)/(3)) where x and y are in metre and t is in second, then the velocity of wave will be…………ms^(-1).
Answer» 300 600 1200 200 Solution :Comparing given equation with general equation, `y= A sin (OMEGA t-kx + PHI)` `omega= 600 (rad)/(s)" and "k= 2 (rad)/(m)` `THEREFORE v= (omega)/(k)` `=(600)/(2)= 300 m"/"s`.

Discussion

2.	Slope of v rarr t graph of body having accelerated motion is …... .
Answer» ANSWER :POSITIVE

Discussion

3.	The adiabatic relation between P and T is
Answer» <P>`P^(1-gamma).T^(gamma)=` CONSTANT `PT^(gamma)=` constant `P^(gamma)T^(1-gamma)=` constant `P^(gamma)T^(gamma-1)=` constant Solution :Some of the EXAMPLES of ISOTHERMAL changes

Discussion

4.	What is the phase difference between the displacement and the velocity of a particle executing SHM?
Answer» SOLUTION :`90^(@)`

Discussion

5.	Water rises to a height of 10cm in a capillary tube and mercury falls to a depth of 3.42cm in the same capillary tube. If the density of mercury is 13.6gm/cc and the angle of contact is 135^(@), ratio of surface tension for water and mercury is
Answer» `1:0.5` `1:3` `1:6.5` `1.5:1` ANSWER :C

Discussion

6.	An inventor claims to have developed an engine working between 600k and 300k of having an efficiency of 52% . Comment on his claims .
Answer» SOLUTION :CLAIM in INVALID

Discussion

7.	When small droplets floating in atmosphere merge into each other in clouds, they become heavy and cannot float in air and fall down as rain drops. In this process of formation of bigger drops if 'n' small drops each of radius 'r', surface tension “T” coalesce. ThenIf P is the excess pressure in a smaller drop, the excess pressure in bigger drop is
Answer» <P>`P` `N^(1//3) P` `( P)/( n^(1//3))` `NP` ANSWER :C

Discussion

8.	A pendulum of length L swings from rest to rest n times in one second. The value of acceleration due to gravity is
Answer» `4pi^2 n^2L` `2pi^2 n^2L` `pi^2 n^2L` `(pi^2 n^2L)/2` ANSWER :A

Discussion

9.	A bird resting on the floor of an air tight box is being carried by a boy. If the bird starts flying, he feels the box as
Answer» HEAVIER Lighter Of same WEIGHT as before Lighter in the BEGINNING and heavier after wards Answer :C

Discussion

10.	Two parallel rail tracks run north-south. Train A moves north with a speed of 54kmh^(-1), and train B moves south with a speed of 90kmh^(-1). What is the (a) velocity of B with respect to A? (b) velocity of ground with respect to B?And (c ) velocity of a monkey running on the roof of the train A against its motion (with a velocityof 18 kmh^(-1) with respect to the train A) as observed by a man standing on the ground?
Answer» Solution :`v_(A)=+54kmh^(-1)=15ms^(-1)` `v_(B)=-90kmh^(-1)=-25ms^(-1)` Relative velocity of B with respect to A is `V_(BA)=V_(B)-V_(A)=-40MS^(-1)` i.e. the train B appears to A to move with a SPEED of 40 m s-1 from NORTH to south. Relative velocity of ground with respect to B is `V_(GB)=0-v_(B)=25ms^(-1)` In (c ), let the velocity of the monkey with respect to ground be `v_(M)`. Relative velocity of the monkey with respect to A. `v_(MA)=v_(M)-v_(A)=-18kmh^(-1)=-5MS^(-1)` Therefore, `v_(M)=v_(MA)+v_(A)=(-5+15)ms^(-1)=10ms^(-1)`.

Discussion

11.	When small droplets floating in atmosphere merge into each other in clouds, they become heavy and cannot float in air and fall down as rain drops. In this process of formation of bigger drops if 'n' small drops each of radius 'r', surface tension “T” coalesce. ThenWhen smaller drops combine energy is released or absorbed, which is given by
Answer» ENERGY released`= 4 pi R^3 ((1)/(R ) - (1)/(r ) )T` Energy released `= 4 piR^3 ((1)/(r) - (1)/(R ))T ` Energy absorbed `= 4PI R^3 ((1)/(R) - (1)/( r ) ) T ` Energy absorbed `= 4pi R^3 ((1)/(r )-(1)/(R )) T` Answer :B

Discussion

12.	The pressure of gas is decided by
Answer» RANDOM COLLISIONS on unit area average collisions per SECOND on unit area average COLLISION on unit area random collisions per second on unit area Answer :B

Discussion

13.	A copper and a steel wire of the same diameter are connected end to end. A deforming force Fis applied to this composite wire which causes a total elongation of 1 cm. The two wires will have
Answer» the same STRESS different stress the same strain different strain Solution :In stress `= F/A,` F is defoeming force and A is constant. `therefore` Hence, stress is same so option (A) is correct. `implies ` Strain `= F/Y` Both wire having same DEFORMING force but different Young.s MODULUS and hence two wires will have different strain so, option (D) is correct.

Discussion

14.	The wavelength of maximum emitted energy of a body at 700K is 4.08 mum. If the temperature of the body is raised to 1400 K, the wavelength of maximum emitted energy the wavelenght of maximum emitte energy will be
Answer» 1.02 `MU`m `16.32 mu `m `8.16 mu `m `2.04 mu`m Answer :D

Discussion

15.	What are the advantages of SI ?
Answer» SOLUTION :1 (B) 10

Discussion

16.	A spring is stretched by applying a load to its free end. The strain produced in the spring is
Answer» VOLUME STRAIN SHEARING strain Tensile strain None of the above Answer :B

Discussion

17.	In case of an orbiting satellite if the radius of orbit is decreased
Answer» its KINETIC energy decreases its potentia energy increases Both (a) and (b) are correct Both (a) and (b) are wrong Solution :As kinetic energy, `K=(GMM)/(2r)` Potentialm energy, `U=-(GMm)/(R)` Total energy, `E=-(GMm)/(2r)` If `r` is decreased, K will increase but U and E will DECREASE.

Discussion

18.	If a spring of force constant K, is cut into three equal parts, then the force constant of each part will be
Answer» `K//3` `K` `3K` `6K` ANSWER :C

Discussion

19.	One mole of an ideal gas is taken from state A to state B as shown (P_(A)=2P_(0), V_(A)=V_(0)" and "P_(B)=P_(0), V_(B)=2V_(0)). Find the maximum temperature attained during this process ?
Answer» ANSWER :`(9P_(0)V_(0))/(4R)`

Discussion

20.	An open pipe40 cm long a closed pipe 31 cm long , both having same diameter , are producing their first overtone , and these are in unison. Determine the end correction of these pipes.
Answer» Solution :Let `v` be the VELOCITY of sound and `f` be the frequency of the NOTE. Thus , the wavelength of sound produced is `lambda = (v)/(f)` The wavelength of first overtone of OPEN pipe is ` lambda_(1) = L + 2 e = 40 + 2E` `(v)/(f) = 40 + 2e``(:. lambda_(1)= lambda)` The wavelength of first overtone of closed pipe is `(3)/(4) lambda_(1) = l + e = 31 + e` `(3)/(4) ((v)/(f)) = 31 + e``( :. lambda_(1) = lambda)` By eliminating `v//f` from the above two equations , we get `(3)/(4) ( 40 + 2 e) = 31 + e` `rArr e = 2 cm`

Discussion

21.	Calculate the moment of inertia of a.unifprm disc of mass 0.4 kg and radius 0.1m about an axis passing through its edge and perpendicular to the plane of die disc ?
Answer» SOLUTION :`I=(3//2)MR^(2) = (3//2) xx 0.4 xx 0.1^(2) = 6 X 10^(-3) kg m^(2)`

Discussion

22.	If vec(A)= 5 hat(i) - 2hat(j) + 3hat(k) and vec(B)= 2hat(i) + hat(j) + 2hat(k), component of vec(B) along vec(A) is
Answer» `(SQRT14)/(38)` `(28)/(sqrt38)` `(sqrt28)/(38)` `(14)/(sqrt38)` ANSWER :D

Discussion

23.	A solid sphere rolls down without slipping from rest on a 30^(@) incline. Its linear acceleration is
Answer» `5g//7` `5g//14` `2g//3` `g//3` ANSWER :B

Discussion

24.	For 1 mole of an ideal gas, during an adiabaticprocess, the square of the pressure of a gas is found to be proportional to the cube of its absolute temperature. The specific heat of the gas at constant volume is (R - universal gas constant)
Answer» 3R `(R )/(2)` `(R )/(3)` 2R ANSWER :B

Discussion

25.	If a planet of mass 'm' is revolving around the sun in a circular orbit of radius 'r' with time period T, then the mass of the sun is
Answer» `(4PI^(2) R^(3))/(G T)` `(4pi^(2) r^(3))/(G T^(2))` `(4pi^(2) r)/(G T)` `(4pi^(2) r^(3))/(G^(2) T^(2))` Answer :B

Discussion

26.	The rate of emission of radiation of a black body at temperature 27^(@)C is E_(1). If its temperature is increased to 327oC the rate of emission of radiation is Ee_(2). The relation between E_(1) and E_(2) is
Answer» `E_(2) = 24 E_(1)` `E_(2) = 16 E_(1)` `E_(1) = 8 _(1) ` `E_(2) = 4 E_(1) ` ANSWER :B

Discussion

27.	Density of ice is rho and thatof water is sigma .What will be from following decrease in volume when a mass M of ice melts ?
Answer» `(M)/(sigma-RHO)` `(sigma-rho)/(M)` `M[(1)/(rho)-(1)/(sigma)]` `(1)/(M)[(1)/(rho)-(1)/(sigma)]` Solution :VOLUME of ICE `V_(1)=(M)/(rho)` Volume of water `V_(2)=(M)/(sigma)` If `V_(1)gtV_(2)` , volume decreases for MELTING of ice . DECREASE in volume `=V_(1)-V_(2)=(M)/(rho)=(M)/(sigma)` `=M[(1)/(rho)-(1)/(sigma)]`

Discussion

28.	State the dimensional formula of (1) moment of inertia (ii) radius of gyration
Answer» Solution : Moment of inertia Unit: KG. m. Dimensional formula : `ML^(2)` RADIUS of gyration K. Unit: meter. Dimensional formula :`L^(1)`

Discussion

29.	''Conduction stops once rod achieves thermal steady state.''
Answer» Solution :CONDUCTION doesn.t stop but heat transfer rate becomes CONSTANT.

Discussion

30.	The elongation of a steel wire, stretched by a force is e. If a wire of the same material, double the length and half the diameter is subjected to double the force, its elongation will be
Answer» `16e` `4E` `(1//4)E` `(1//16)e` ANSWER :A

Discussion

31.	A block is sliding on a rough horizontal surface. If the contact force on the block is sqrt(2) times the frictional force, the coefficient of friction is
Answer» `0.25` `(1)/(SQRT(2))` `sqrt(2)` 1 Answer :D

Discussion

32.	0.2 moles of an ideal gas is taken round the cycle ABC as shown in the figure. The path B rarr C is an adiabatic process A rarr B is an isochoric process and C rarr A is an isobaric process. The temperature at A and B are T_(A)300 K and T_(B) = 500 k and pressure at A is 1 atm and volume at A is 4.91. The volume at C is (given : gamma = (C_(P))/(C_(V)) = (5)/(3), R = 8.205 xx 10^(-2) L "atm mol"^(-1) K^(-1), ((3)/(2))^(2//5) = 0.81)
Answer» 6.9 L 6.6 L 5.5 L 5.8 L Solution :For `A RARR B`, volume is CONSTANT `:. (P_(A))/(T_(A)) = (P_(B))/(T_(B))` or `P_(B) = (T_(B))/(T_(A)) xx P_(A) = (500)/(300) xx 1 = (5)/(3)` ATM For `B rarr C`, adiabatic process `:. (T_(C )^(gamma))/(P_(C )^(gamma - 1)) = (T_(B)^(gamma))/(P_(B)^(gamma - 1))` or `T_(C ) = ((P_(C ))/(P_(B)))^((gamma - 1)/(gamma)) xx T_(B) = [(1)/(5//3)]^(((5//3)-1)/((5//3))) xx 500` (Using (i)) `= ((3)/(5))^(2//5) xx 500` For `C rarr A`, pressure is constant `:. (V_(C ))/(T_(C )) = (V_(A))/(T_(A))` or `V_(C ) = V_(A) xx (T_(C ))/(T_(A)) = 4.9 xx ((3)/(5))^(2//5) xx 500 xx (1)/(300)` (Using (ii)) `= 4.9 xx 0.81 xx (5)/(3) = 6.6 L`

Discussion

33.	A machine gun is mounted on a flat railroad car . The gun is firing bullets at the rate of 10 bullets per second each of mass 10 g . The bullets come out with velocity 500 m s^(-1) relative to the car. Calculate the acceleration of the car at the instant when its mass is 200 kg . Also calculate the force at that instant.
Answer» ANSWER :`0.25 m s^(-2) , 50 N `

Discussion

34.	The amplitude of a damped oscillator becomes half in one minute. The amplitude after 3 minutes will be (1)/(x) time the original, where x is……………
Answer» `2XX3` `2^(3)` `3^(2)` `3xx2^(2)` Solution :The AMPLITUDE decreases exponentially with time and becomes HALF in 1 minute. Amplitude after 3 minutes = `((1)/(2))^(3)` of the original value. Thus, `x=2^(3)`

Discussion

35.	A system of four masses m_1, m_2,m_3, m_4, my two springs and a fixed pulley is shown in figure. The system is kept at rest by attaching the lower thread to a rigid peg. Determine the acceleration of all the masses after the lower thread has been cut. The springs are massless, pulley is frictionless and massless.
Answer» Solution :Clearly `(m_1 + m_2) gt (m_3 + m_4)` . Let `T_1` be the tension in left SPRING and `T_2` that in right spring and T is tension in the string passing over the pulley . Then for equilibrium of system `T_1 =m_2g , T=(m_1 + m_2)G`...........(2) and `m_3g + T_2=T` From last equation `T_2 =T-m_3g=(m_1 + m_2-m_3)g` ........ (3) After the lower THREAD is cut off Equation of motion of mass `m_1` is `m_1g + T_1-T = m_2a_3` .......... (4) Equation of motion of mass `m_2` is `m_2g -T_1 = m_2a_2` ...........(5) Equation of motion mass ` m_3` is `m_3g + T_2 -T = m_1 a_1`............. (6) Equation of motion of mass `m_4` is `m_4g -T_2 =m_4a_4` ............. (7) Using (1) , (2) and (3) we get ` a_1= a_2 = a_3 =0` ` and a_4 = (m_4g -T_2)/( m_4) =(m_4g(m_1 + m_2 - m_3)g)/( m_4) = ((m_3 + m_4 - m_1 - m_2)g)/(m_4)`

Discussion

36.	The gravitational field in a region is given by vecE =(4hati+3hatj)N//Kg. The gravitational potential at the points (3m, 0 ) and (0, 4m). If the potential at the origin is taken by zero .
Answer» SOLUTION :`VECV=-(vecE.vecr)` At (3m,0) `vecV = - (4hati+3hatj).(3HATI)=-12J//Kg` At (0,4m) `vecV=-(4hati+3hatj).(4hatj)=-12J//Kg`

Discussion

37.	A ray of monochromatic light is incident on one refracting face of a prism of angle 75^@. IT passes through the prism and is incident on the other face at the critical angle. If the refractive index of the material of the prism is sqrt2, the angle of incidence on the first face of the prism is
Answer» `30^@` `45^@` `60^@` `0^@` ANSWER :B

Discussion

38.	The mean radius of a wire is 2 mm. Which of the following measurements is most accurate?
Answer» 1.9 MM 2.25 mm 2.3 mm 1.83 mm Solution :1.9 mm

Discussion

39.	A man standing on the edge of the roof of a 20 m tall building projects a ball of mass 200 g vertically up with a speed of 10 ms^(-1) and simultaneously throws another ball of same mass vertically down with the same speed. Find the kinetic energy of each ball when they reach the ground (g = 10 ms^(-2)).
Answer» ANSWER :50 J, 50 J

Discussion

40.	How is average velocity different from instantaneous velocity ?
Answer» Solution : Average velocity:It is defined as RATIO `Deltax` displacement to the time interval `Deltat vecv_(x)=(Deltax)/(Deltat)-(x_(2)-x_(1))/(t_(2)-t_(1))` Average velocity is independent of the path followed by the particle between initial and final positions INSTANTANEOUS velocity: The velocity of a particle at a particular instant of time is KNOWN as instantaneous velocity i.e., `v_(x)=L_(Deltatrarr0)(Deltax)/(Deltat)=(dx)/(dt)` Instantaneous velocity is the RATE of CHANGE of position with time.

Discussion

41.	Two wires A and B have the same length and area of cross-secton. But Young's modulus of A is two times the Young's modulus of B. Then the ratio of force constant of A to that of B is
Answer» 1 2 `1//2` `SQRT2` ANSWER :B

Discussion

42.	Classical physics is inadequate to deal with
Answer» RIGID bodies, deformable bodies, electrons Rigid BODY, deformable bodies, system of PARTICLES Electrons, photons, ELEMENTARY particles Rigid bodies, photons, electrons Answer :B

Discussion

43.	The nature of materials in mutual contact decides
Answer» `MUS ` `MUK` `mu s " or" mu k` none SOLUTION :`mu s " or" mu k`

Discussion

44.	If the external force acting on a system of particle is zero then …………..
Answer» `vec(a)_(cm)=0` `vec(V)_(cm)=0` `vec(R )_(cm)=0` `vecp=0` SOLUTION :`vecF=Mveca_(cm)` `0=Mveca_(cm)` `therefore 0=veca_(cm)`

Discussion

45.	What is the excess of pressure inside the spherical drop of water of radius 1mm. Surface tension of water is 70xx10^(-3)N//m.
Answer» <P> SOLUTION :Radius of water drop, `R=1mm=1xx10^(-3)m` SURFACE tension of water, `S=70xx10^(-3)Nm^(-1)` EXCESS pressure inside the drop, `P=(2S)/(r)=(2xx70xx10^(-3))/(1xx10^(-3))=140Nm^(-2)`.

Discussion

46.	Graph shows a hypothetical speed distribution for a sample of N gas particle (for V gt V_(0), (dN)/(dV) = 0)
Answer» The value of `V_(0)` is `2N` The ratio `V_(AVG)//V_(0)` is equal to `2//3` The ratio `V_(rms)//V_(0)` is equal to `1//sqrt(2)` THREE fourth of the total particle has a speed between `0.5 V_(0)` and `V_(0)`. Answer :A::B::C::D

Discussion

47.	Which of the following represents a wave?
Answer» `(1)/(X+vt)` `SIN(x+vt)` `(x-vt)^(3)` `x(x+vt)` Answer :B

Discussion

48.	On a planet, a body is let fall freely from a height 8m reaches the ground in 2 sec. If the length of a simple pendulum is 1m on that planet, its time period is
Answer» 3.14sec 6.24 sec 1.57 sec 4.71 sec Answer :A

Discussion

49.	Mand M/sqrt(3) are the magnetic dipole moments of the two magnets, which are joined to form a cross figure. Find the inclination of the system with the field, if their combination is suspended freely in a uniform external magnetic field B.
Answer» `theta = 30^(@)` `theta = 45^(@)` `theta = 60^(@)` `theta = 15^(@)` Solution :TORQUE `(tau)` ACTING on magnet (1). `""tau_(1)=MBsintheta` `"Similarly"tau_(2)=SQRT(3)MBsintheta` `therefore""theta=60^(@)` But for equilibrium,`tau_(1)=tau_(2)` `therefore ""MBsintheta=sqrt(3)MBcostheta` `""tan theta=sqrt(3)=tan60^(@)` `therefore""theta=60^(@)`

Discussion

50.	Four engines are working between Which one has maximum efficiency ?
Answer» 100 K and 80 K 40 K and 20 K 60 K and 40 K 120 K and 100 K Solution :EFFICIENCY, `ETA = 1 - (T_(2))/(T_(1)) = (T_(1) - T_(2))/(T_(1))` In all the given four cases, `T_(1) - T_(2) = 20 K` `:. eta` is highest when `T_(1)` is LOWEST. `:.` At option (b), 40 K and 20 K, has maximum efficiency.

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

In the equation of motion of waves in x-direction is given by y= 10^(-4) sin(600t-2x+(pi)/(3)) where x and y are in metre and t is in second, then the velocity of wave will be…………ms^(-1).

Slope of v rarr t graph of body having accelerated motion is …... .

The adiabatic relation between P and T is

What is the phase difference between the displacement and the velocity of a particle executing SHM?

Water rises to a height of 10cm in a capillary tube and mercury falls to a depth of 3.42cm in the same capillary tube. If the density of mercury is 13.6gm/cc and the angle of contact is 135^(@), ratio of surface tension for water and mercury is

An inventor claims to have developed an engine working between 600k and 300k of having an efficiency of 52% . Comment on his claims .

A pendulum of length L swings from rest to rest n times in one second. The value of acceleration due to gravity is

A bird resting on the floor of an air tight box is being carried by a boy. If the bird starts flying, he feels the box as

The pressure of gas is decided by

A copper and a steel wire of the same diameter are connected end to end. A deforming force Fis applied to this composite wire which causes a total elongation of 1 cm. The two wires will have

The wavelength of maximum emitted energy of a body at 700K is 4.08 mum. If the temperature of the body is raised to 1400 K, the wavelength of maximum emitted energy the wavelenght of maximum emitte energy will be

What are the advantages of SI ?

A spring is stretched by applying a load to its free end. The strain produced in the spring is

In case of an orbiting satellite if the radius of orbit is decreased

If a spring of force constant K, is cut into three equal parts, then the force constant of each part will be

One mole of an ideal gas is taken from state A to state B as shown (P_(A)=2P_(0), V_(A)=V_(0)" and "P_(B)=P_(0), V_(B)=2V_(0)). Find the maximum temperature attained during this process ?

An open pipe40 cm long a closed pipe 31 cm long , both having same diameter , are producing their first overtone , and these are in unison. Determine the end correction of these pipes.

Calculate the moment of inertia of a.unifprm disc of mass 0.4 kg and radius 0.1m about an axis passing through its edge and perpendicular to the plane of die disc ?

If vec(A)= 5 hat(i) - 2hat(j) + 3hat(k) and vec(B)= 2hat(i) + hat(j) + 2hat(k), component of vec(B) along vec(A) is

A solid sphere rolls down without slipping from rest on a 30^(@) incline. Its linear acceleration is

For 1 mole of an ideal gas, during an adiabaticprocess, the square of the pressure of a gas is found to be proportional to the cube of its absolute temperature. The specific heat of the gas at constant volume is (R - universal gas constant)

If a planet of mass 'm' is revolving around the sun in a circular orbit of radius 'r' with time period T, then the mass of the sun is

The rate of emission of radiation of a black body at temperature 27^(@)C is E_(1). If its temperature is increased to 327oC the rate of emission of radiation is Ee_(2). The relation between E_(1) and E_(2) is

Density of ice is rho and thatof water is sigma .What will be from following decrease in volume when a mass M of ice melts ?

State the dimensional formula of (1) moment of inertia (ii) radius of gyration

''Conduction stops once rod achieves thermal steady state.''

The elongation of a steel wire, stretched by a force is e. If a wire of the same material, double the length and half the diameter is subjected to double the force, its elongation will be

A block is sliding on a rough horizontal surface. If the contact force on the block is sqrt(2) times the frictional force, the coefficient of friction is

The amplitude of a damped oscillator becomes half in one minute. The amplitude after 3 minutes will be (1)/(x) time the original, where x is……………

The gravitational field in a region is given by vecE =(4hati+3hatj)N//Kg. The gravitational potential at the points (3m, 0 ) and (0, 4m). If the potential at the origin is taken by zero .

A ray of monochromatic light is incident on one refracting face of a prism of angle 75^@. IT passes through the prism and is incident on the other face at the critical angle. If the refractive index of the material of the prism is sqrt2, the angle of incidence on the first face of the prism is

The mean radius of a wire is 2 mm. Which of the following measurements is most accurate?

How is average velocity different from instantaneous velocity ?

Two wires A and B have the same length and area of cross-secton. But Young's modulus of A is two times the Young's modulus of B. Then the ratio of force constant of A to that of B is

Classical physics is inadequate to deal with

The nature of materials in mutual contact decides

If the external force acting on a system of particle is zero then …………..

What is the excess of pressure inside the spherical drop of water of radius 1mm. Surface tension of water is 70xx10^(-3)N//m.

Graph shows a hypothetical speed distribution for a sample of N gas particle (for V gt V_(0), (dN)/(dV) = 0)

Which of the following represents a wave?

On a planet, a body is let fall freely from a height 8m reaches the ground in 2 sec. If the length of a simple pendulum is 1m on that planet, its time period is

Mand M/sqrt(3) are the magnetic dipole moments of the two magnets, which are joined to form a cross figure. Find the inclination of the system with the field, if their combination is suspended freely in a uniform external magnetic field B.

Four engines are working between Which one has maximum efficiency ?