40048 + Interview Questions in Physics in Class 11

1.	Can we use pendulum clock inside an artifical statellite ?
Answer» Solution :No, In an artifical statellite, a BODY is in a state of WEIGHTLESSNESS I i.e., g=0 `:. T= 2pi SQRT((L)/(g))=oo` (infinity). Inside the statllite, the pendulum does not oscillate. HENCE a pendulum clock cannot be used an artifical statellite.

Discussion

2.	The distance between to stars of masses M and 16M is 10 a. their radii a and 2a respectively. A body of mass m is fired stright from the surface of larger star towards the smaller star. If the speed of projection to reach the surface of smaller star is (X)/(2) sqrt((yGm)/(a)) then find the value of x + y
Answer» ANSWER :8

Discussion

3.	Does the absolute value of potential energy have any physical significance ?
Answer» SOLUTION :No, it is DIFFERENCE of POTENTIAL ENERGIES that MATTERS.

Discussion

4.	barF=abari+3barj+6bark and barr=2bari-6barj-12bark. The value of 'a' for which the angular momentum is conserved is
Answer» `-1` `0` `1` `2` ANSWER :A

Discussion

5.	Two identical vessels A and B with frictionless pistons contain the same ideal gas at the same temperature and the same volume V. The masses of gaş in A and B are m_(A) and m_(B) respectively. The gases are allowed to expand isothermally to the same final volume 2 V. The change in pressures of the gas in A and B are found to be Deltap and 1.5 Deltap respectively. Then
Answer» `9m_A = 4m_B` `3m_A = 2m_B` `2m_A = 3m_B` `4m_A = 9m_B` ANSWER :B

Discussion

6.	A cylinder of mass 5 kg and radius 30 cm, free to rotate about its axis, receives an angular impulse of 3 kg ms^(-1) initially followed by a similar impulse after every 4s. What is the angular speed of the cylinder 30 s after the initial impulse if the cylinder is at rest initially ?
Answer» Solution :In 30s the cylinder receives 8 ANGULAR impulses INCLUDING the initial impulse `sum tau XX t=I(omega_(2)-omega_(1))` `8xx3=(MR^(2))/(2)omega_(2)(sin CE omega_(1)=0)` `= (5xx(0.3)^(2))/(2)omega_(2)` On solving `omega_(2)=106.7 rad s^(-1)`.

Discussion

7.	Can we determine the gravitational mass of a body inside an artificial satellite?
Answer» Solution :No, we cannot determine the GRAVITATIONAL mass of a BODY INSIDE an artifical satellite.The artificial satellite acts like a freely falling body.In this case, a = g `therefore` Weight F = m(g - g) = 0 Hence weight of the body inside the satellite is ZERO.

Discussion

8.	A block rests on a rough inclined plane making an angle of 30° with the horizontal. The coefficient of static friction between the block and the plane is 0.8. If the frictional force on the block is 10 N, the mass of the block ((in kg) is .......... (Take g = 10 m//s^(2))
Answer» 2.0 kg 4.0 kg 1.6 kg 2.5 kg SOLUTION :Weightof a BLOCK `F= mg` The blockis atrest . Herewehavetakenfrictionalforce= Downwardcomponentof weightalonginclinedplane That is `f= mg sintheta:. ,m= (f )/( G sin theta )` Substituting`f= 10 Ng =10 :. , m = (10)/( 10 sin 30^(@))` But`sin theta= sin 30^(@)= (1)/(2)` we GETM =2kg

Discussion

9.	A uniform solid sphere of mass 0.5 kg rolls on a horizontal surface without slipping. If the velocity of centre of mass is 4 cm s^(-1), the work done in stopping sphere is
Answer» `8XX10^(-4)J` `5.6xx10^(4)J` `1.6xx10^(-4)J` `2.4xx10^(-4)J` ANSWER :B

Discussion

10.	A nail is located below the point of suspension of a simple pendulum of length l. The bob is released from horizontal position. If the bob loops a verticle circle with nail as centre, find the distance of nail from point of suspension.
Answer» Solution :Form the principle of conservation of mechanical energy PE at the horizontal position = KE at the LOWEST position. `mgl = (1)/(2) mv^(2)` To loop the vertical circle , `V^(2)=5g(1-X)` where .x. is the distance of nail from point of SUSPENSION, and .v. is the velocity at lowest point of path. `(mgl=(1)/(2)m.5g (l-x)), l=(5)/(2)(l-x), "" x = 3l//5`

Discussion

11.	A simple pendulum is formed by hanging a sphere of mass of 1 kg from a copper wire of length 5 m and of diameter, 0.08 cm and then the time period of this pendulum is measured. Now the sphere of mass 1 kg is replaced by another sphere of mass 10 kg. Determine the change in time period of the pendulum. [ Y for copper = 12.4xx10^(10)N*m^(-2)]
Answer» ANSWER :4.488 s, 0.0035 s

Discussion

12.	Mass of an electron ........
Answer» `10^(-31)` KG `9.11 XX 10^(-31)` kg `1.6 xx 10^(-31)` kg `1.6 xx 10^(-27)` kg Solution :`9.11 xx 10^(-31)` kg

Discussion

13.	On a hypothetical scale X, the ice point is 40^(0) and the steam point is 120^(0). For another scale Y the ice point and steam points are -30^(0) and 130^(0) respectively. If X-reads 50^(0) The reading of Y is
Answer» `-5^(0)` `-8^(0)` `-10^(0)` `-12^(0)` ANSWER :C

Discussion

14.	A body is rotating uniformaly about vertical axis fixed in an intertial frame. The resultant force on a particle of the body not on the axis is
Answer» VERTICAL horizontal and SKEW with the AXIS horizontal and INTERSECTING the axis none of these Answer :C

Discussion

15.	The linear variable of all particles are same in rotational motion of rigid body.
Answer» Solution :Linear variables `vecr,vecv and VECA` of all PARTICLES of rigid body are different in rotational motion, means they are not same. Different particles have different position vectors `(vecr)`. Hence linear velocity `vecv=rvecomega` also different. The value of linear velocity of particle near to the axis is less the value of linear velocity of particle FAR from the axis because angular velocity `vecomega` is same for all particle and so in linear acceleration `\|veca\|=sqrt(((v^(2))/(R))^(2)+(ralpha)^(2))` velocity changes. So it is not same.

Discussion

16.	The force constant of a particle of mass 1kg is SHM of amplitude 4cm is 100N//m when particle is at mean position at t = 0 then find maximum speed.
Answer» `0.4 m//s` `0.6 m//s` `0.8 m//s` 1 sec Answer :A

Discussion

17.	Surface tension does not depends on ……… .
Answer» (a) nature of the liquid (b) TEMPERATURE of the liquid (c) ATMOSPHERIC PRESSURE (d) presence of impurities ANSWER :C

Discussion

18.	One body is displaced in the direction of X - axis up to 4 meter under influence of (-1,2,3) N force. Find work done by the force .
Answer» SOLUTION :` W = VEC(F) .vec(d) = (-1,2,3).(4,0,0)` `= - 4` JOULE .

Discussion

19.	A projectile moving vertically upwards with a velocity of 200 m/s breaks into two equal parts at the height of 490 m. One part starts moving vertically upwards with a velocity of 400 m/s. How much time after the break up will the other part hit the ground?
Answer» `sqrt10s` `2sqrt10s` 5s 10s Answer :B

Discussion

20.	Assertion :The amplitude of forced oscillation are constant. Reason : No external force acts on forced oscillator.
Answer» Both are ture and the REASON is the correct EXPLANATION of the ASSERTION. Both are ture and the reason is not correct explanation of the assertion. Assertion is TRUE, but the reason is false. Both assertion and reason are false. Answer :C

Discussion

21.	A simple pendulum of length 'l' carries a bob of mass 'm'. The bob is released from horizontal position. The tension in the string at the lowest point would be
Answer» mg 2mg 3mg 4mg Answer :C

Discussion

22.	A vertical U - tube of uniform cross - section contains water in both the arms. A 10 cm glycerine column (R.D. = 1.2) is added to one of the limbs. What is the level difference between the two free surface in the two limbs?
Answer» Solution :Let the DIFFERENCE between TWO limbs be x PRESSURE on the line Y, should be same below both limbs, so `rho_("glycerine")xxg xxh=rho_("WATER")xx(h+x)` `RARR 1.2xx10=1xx(h+x)` `rArr 2cm=x`

Discussion

23.	Establish Newton's third law from Newton's second law.
Answer» Solution :Section Newton.s third LAW of motion from the law of CONSERVATION of linear momentum. NOTE: From Newton.s second law, the RATE of change of momentum of the first body = forces on the first body (by second body)

Discussion

24.	Two bodies of masses 10 kg and 20 kg respectively kept on a smooth, horizontal surface are tied to the ends of a light string. A horizontal force F = 600 N is applied to (i) A, (ii) B along the direction of string. What is the tension in the string in each case?
Answer» Solution : If the 20 kg mass is PULLED, 600 – T = 20 a, T = 10 a `a = 20 MS^(-2)`T = 200N If the 10 kg mass is pulled , ` a = 20 ms^(-2)` ,T = 400N

Discussion

25.	Which is greater , the attreaction of the earth ona1kg body or the attraction of the 1kg body on the earth ?
Answer» SOLUTION :Both are EQUAL .

Discussion

26.	A moving shere P collides another shere Q at rest. If the collision takes place along the line joining their centres of mass such that their total kinetic energy is conserved and the fraction of K.E transferred by the colliding particle is 8"/"9, the ratio of mass of P and the mass of Q is
Answer» `SQRT(8) : 3` `9 : 8` `2 : 3` `1 : 2` Answer :D

Discussion

27.	Water is flowing with a speed of 2 ms^(-1) in a horizontal pipe with cross-sectional area decreasing from 2 xx 10^(-2) m^(2) to 0.01 m^2 at pressure 4 xx 10^4 Pa. What will be the pressure at small cross-section ?
Answer» Solution :Here , `v_1 = 2 ms^(-1) , a_1 = 2 xx 10^(-2) m^2, a^2 = 0.01 m^2 , P_1 = 3 xx 10^(4) Pa, P_2 = ? , rho = 10^3 KG m^(-3)` `v_2 = (a_1v_1)/(a_2) = (2 xx 10^(-2) xx 2)/(0.01) = 4 ms^(-1)` As `"" P_1 + 1/2 rho v_1^2 = P_2 + 1/2 rho v_2^2` `"" P_2 = P_1 - 1/2 rho (v_1^2 - v_2^2)` `= 4 xx 10^4 - 1/2 xx 10^3 (2^2 - 4^2)` `P_2 = 3.4 xx 10^(4)Pa`

Discussion

28.	Why does a flag flutter when there is wind ?
Answer» Solution :Due to pressure difference on the two SIDES of the FLAG, produced by the high VELOCITY stream of AIR.

Discussion

29.	Three sound waves of equal amplitude have frequencies (n-1), n, (n + 1). They superimpose to give beats. The number of beats produced per second will be ?
Answer» 3 2 1 4 Solution :Maximum no. of beats per UNIT TIME, `= f _(MAX) -f _(MIN)` `= (n +1) --(n-1)=2`

Discussion

30.	A steam at 100^(@)C is passed into 1kg of water contained in a calorimeter of water equivalent 0.2kg at 9^(@)C, till the temperature of the calorimeter and water in it is increased to 90^(@)C. The mass of steam condensed in kg is nearly (sp. Heat of water = 1"cal"//g.""^(@)C, Latent heat of vaporization = 540 cal/g)
Answer» 0.81 0.18 0.27 0.54 Answer :B

Discussion

31.	State the importance of work energy theorem .
Answer» Solution :(1) If the change in KINETIC ENERGY `DeltaK ` of a body is zero , then the work done on the body is zero and itskinetic energy remains constantand hence the speed of the body remains constant . For example : the speed of a particle in UNIFORM CIRCULAR motion is constant and work done is zero . (2) If the displacement of a body is in the same direction of force or dispalce MENT is in direction of component of force then the work done on the body and hence the kinetic energyof body increases . For example ,free fall body . (3) If the dispalcement of a body is opposite in the direction of force or displacement is in the opposite direction of component of force then the work done by the body and hence , the kinetic energy of body decreases .

Discussion

32.	A small sphere of mass 1 kg is rolling without slipping with linear speed v=sqrt((200)/(7)) m/s. It leaves the inclined plane at point C. The ration rotational and translational kinetic energy of the sphere when it strikes the ground after leaving from point C.
Answer» `2/5` `2/3` `1/6` `1/2` ANSWER :C

Discussion

33.	In case of a metal scale
Answer» the distance between any two SCALE DIVISIONS does not vary with temperature the distance between any two scale divisions increases in the ratio of `1:(1+alphat)` at HIGHER temperature the distance between any two scale divisions is higher than the true distance in the ratio `(1+alphat):1` at a lower temperature none of the above Answer :A::B::C

Discussion

34.	A Carnot cycle has the reversible processes in the following order :
Answer» ISOTHERMAL EXPANSION, ADIABATIC expansion, isothermal COMPRESSION and adiabatic compression Isothermal compression, adibatic expansion, isothermal expansion and adiabatic compression. Isothermal expansion, adiabatic compression, isothermal compression and adibatic expansion Adiabatic expansion, isothermal expansion, adiabatic compression and isothermal compression. Answer :A

Discussion

35.	A block slides down a rough inclined plane of slope angle theta with a constant velocity. It is then projected up the same plane with an initial velocity v. The distance travelled by the block up the plane before coming to rest is
Answer» `(v^(2))/(4G sin theta)` `(v^(2))/(2g sin theta)` `(v^(2))/(g sin theta)` `(4gv^(2))/(sin theta)` Solution :`a_(d)=g(sin theta-mu_(k)COSTHETA)` `a_(u)=g(sin theta+mu_(k)cos theta), v^(2)-u^(2)=2AS`

Discussion

36.	The two thigh bones (femurs),each of cross - sectional area 10cm^(2) supportthe upper part of a human body of mass 50kg Estimate the average pressure sustained by the femurs. (g=10ms^(-2)).
Answer» SOLUTION :AVERAGE PRESSURE `=2.45xx10^(5)NM^(-2))`

Discussion

37.	Figure shows the vibration of energy with the orbit radius r of satellite ina circular energy motion. Mark the correct statement.
Answer» C SHOWS the total ENERYG. B the kientic energy and A the potential energy of the satellite. A shows the kinetic energy, B the total energy and C the potential energy of the satellite A and B are the kientic and potential energies and C total energy of the satellite C and A are the kinetic energy and potential energies respectively and B the total energy of the satellite. Answer :C

Discussion

38.	A narrow sound pulse( for example, a short pip by a whistle ) is sent across a medium(i) Does the pulse have a definite (a) frequency , (b) wevelength , ( M69)speed of propagation?(ii) If the pulse rate is 1 after every 20s , (that is the whistle is blown for a split of second after every 20 s ) , is the frequency of the note produced by the whistle equal to 1/20 or 0.05 Hz ?
Answer» SOLUTION :N/A

Discussion

39.	What is the excess pressure inside a bubble of soap solution of radius 5.00 mm , given that the surface of soap solution at the temperature (20^(@)C) is 2.50xx10^(-2)Nm^(-1) ?If an air bubble of the same dimension were formed at depth of40.0 cm inside a container containing the soap solution (of relative density 1.20) , what would be the pressure is 1.01xx10^(5)Pa).
Answer» SOLUTION :Excess pressure inside soap bubble , `P_(i)-P_(o)=(4S)/(R)=(4xx2.5XX10^(-2))/(5xx10^(-3))=20Pa` Excess pressure inside the soap bubble in air, `P_(i)-P_(o)=(2S)/(R)=(2xx2.5xx10^(-2))/(5xx10^(-3))=10Pa` Inside pressure air bubble at depth of 40 cm , `P_(i)=P_(0)+(2S)/(r)` `=1.01xx10^(5)+hrhog+(2S)/(r)` `=1.01xx10^(5)+0.4xx1.2xx10^(3)xx9.8+10` `=1.01xx10^(5)+4.704xx10^(3)+10` `1.01xx10^(5)+0.04704xx10^(5)+10` `=1.05704xx10^(5)PA+10Pa` `=1.06xx10^(5)Pa+0.00010xx10^(5)Pa` `=1.0601xx10^(5)Pa` `=1.06xx10^(5)Pa`

Discussion

40.	Figure. gives a speed-time graph of a particle in motion along a constant direction. Three equal intervals of time are shown. In which interval is the average acceleration greatest in magnitude ? In which interval is the average speed greatest ? Choosing the positive direction as the constant direction of motion, give the signs of v and a in the three intervals. What are the accelerations at the points A, B, C and D ?
Answer» SOLUTION :ACCELERATION magnitude greatest in 2, speed greatest in 3, `upsilon gt 0` in 1, 2 and 3, `a gt 0` in 1 and 3, `a lt 0` in 2, a = 0 at A, B, C, D.

Discussion

41.	A wheel rotating at angular speed of 20rads^(-1), is brought to rest by a constant torque in 4s. If the M.I is 0.2kgm^(2), the work done in first 2s is
Answer» `50J` `30J` `20J` `10J` ANSWER :B

Discussion

42.	The resultant of two forces whose magnitudes are in the ratio 3:5 is 28N. If the angle of their inclination is 60^(@), then find the magnitude of each force.
Answer» Solution :Let`F_(1)"and " F_(2)` be the two forces. Then `F_(1)=3x, F_(2)=5x, R=28N"and"theta= 60^(0)` `R=sqrt(F_(1)^(2)+F_(2)^(2)+2F_(1)F_(2)COS theta)` `rArr28=sqrt((3x)^(2)+(5x)^(2)+2(3x)(5x)cos60^(@))` `rArr 28=sqrt(9x^(2)+25X^(2)+15x^(2))=7x` `rArrx=(28)/7=4,:. F_(1)=3xx4=12N,F_(2)=5xx4=20N`.

Discussion

43.	The first law of thermodynamics is concerned with the conservation of …………………… .
Answer» NUMBER of molecules energy number of moles temperature Answer :B

Discussion

44.	Let vec(A), vec(B) and vec(C ) be unit vectors. Suppose vec(A).vec(B) = vec(A).vec(C ) = 0 and that the angle between vec(B) and vec(C ) is (pi)/(6) " then " vec(A) = +- n[vec(B) xx vec(C )] find the n
Answer» ANSWER :2

Discussion

45.	Derive an expression for potential energy near the surface of the earth
Answer» SOLUTION :The gravitatinal potenetial energy (U) at the same height h is equalto the amount of work requried to take the object from ground to the height h with constant veocity. Let us consider a body of MASS m being moved from ground to the height h aginst the gravitational force as shown. The gravitational force `vecF_(2)`, ACTING on the body is, `vecF_(g)=-mghatj` (as the force is in y direction unit vector `hatj` is used). Herenegative sign implies that the force is acting vertically downwards were the body without acceleration (or with constant velocity), an external applied weapol in magnitude but opposite to that of gravitational force `vecF_(g)`, has to be applied on the body i,.e `vecF_(a)=-vecF_(g)` . This implies that F, = + mg). The positive sign implies that sign implies that the applied forceis in vertically upward direction. Hence, when the body is lifted up its velocity remains unchanged and thus its kinetic energy also remains constant The gravitational potential energy (U) at some height h is equal to the amount of work required to take the object from the ground to that height it. `U=intvecF_(a).dvecr=underset(0)overset(h)int\|vecF_(a)\|\|dvecr\|costheta` Since the displacement and the applied force are in the same upward direction, the angle between them, ` theta= 0^(@)" Hence " cos0^(@) = 1 and \|vecF_(a)\|= mg and \|dvecr\| = dr.` `U=mgunderset(0)overset(h)intdr` `U=mg[R]_(0)^(h)=MGH`

Discussion

46.	The displacement of a particle varies according to the relation X=3 sin 100t+8 cos^(2)50t. Which of the following is//are correct about this motion.
Answer» the motion of the PARTICLE is not `S,H.M`. the amplitude of the `S.H.M.` of the particle is`5` units the amplitude of the resulting `S.H.M.` SI `sqrt(73)` units the maximum displacement of the particle from the origin is `9` units. Solution :FIGURE

Discussion

47.	Under the action of a force, a 3 kg body moves such that x= (t^2)/(2), where position x is in metre and t is in second. What is the work done by the force in first 3 second?
Answer» Solution :`x =(t^2)/2` `V = (DX)/(DT) = (2t)/2 = t, ((dx)/(dt))_(t=0) = 0 and ((dx)/(dt))_(t=3) = 3 ms^(-1)` `W = DELTA k = 1/2 m(v^2 - u^2) = 1/2 xx 3 xx [3^2 - 0^2] = 13.5 J`.

Discussion

48.	A body executes simple harmonic motion. The potential energy (PE), kinetic energy (KE) and total energy (TE) are measured as a function of displacement x. Which of the following statements is true ?
Answer» TE is ZERO when x = 0 PE is MAXIMUM when x = 0 KE is maximum when x = 0 KE is maximum when x is maximum ANSWER :C

Discussion

49.	What will happen if the upper part of a ship is made heavier than its lower part?
Answer» Solution :If the upper PART of a ship is made heavier than its lower part, then the CENTRE of gravity of the ship lies above the centre of gravity of the water displaced by the ship. As a result, if the ship is tilted a LITTLE, then, due to the couple that DEVELOPS due to the weight of the ship and the buoyant force, the ship tilts more and HENCE it may turn over.

Discussion

50.	When an angular momentum of the object will be zero?
Answer» Solution :If the straight PATH of the particle PASSES through the ORIGIN, then the ANGULAR momentum is zero, which is also a constant.

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

Can we use pendulum clock inside an artifical statellite ?

Does the absolute value of potential energy have any physical significance ?

barF=abari+3barj+6bark and barr=2bari-6barj-12bark. The value of 'a' for which the angular momentum is conserved is

A cylinder of mass 5 kg and radius 30 cm, free to rotate about its axis, receives an angular impulse of 3 kg ms^(-1) initially followed by a similar impulse after every 4s. What is the angular speed of the cylinder 30 s after the initial impulse if the cylinder is at rest initially ?

Can we determine the gravitational mass of a body inside an artificial satellite?

A block rests on a rough inclined plane making an angle of 30° with the horizontal. The coefficient of static friction between the block and the plane is 0.8. If the frictional force on the block is 10 N, the mass of the block ((in kg) is .......... (Take g = 10 m//s^(2))

A uniform solid sphere of mass 0.5 kg rolls on a horizontal surface without slipping. If the velocity of centre of mass is 4 cm s^(-1), the work done in stopping sphere is

A nail is located below the point of suspension of a simple pendulum of length l. The bob is released from horizontal position. If the bob loops a verticle circle with nail as centre, find the distance of nail from point of suspension.

Mass of an electron ........

On a hypothetical scale X, the ice point is 40^(0) and the steam point is 120^(0). For another scale Y the ice point and steam points are -30^(0) and 130^(0) respectively. If X-reads 50^(0) The reading of Y is

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The linear variable of all particles are same in rotational motion of rigid body.

The force constant of a particle of mass 1kg is SHM of amplitude 4cm is 100N//m when particle is at mean position at t = 0 then find maximum speed.

Surface tension does not depends on ……… .

One body is displaced in the direction of X - axis up to 4 meter under influence of (-1,2,3) N force. Find work done by the force .

A projectile moving vertically upwards with a velocity of 200 m/s breaks into two equal parts at the height of 490 m. One part starts moving vertically upwards with a velocity of 400 m/s. How much time after the break up will the other part hit the ground?

Assertion :The amplitude of forced oscillation are constant. Reason : No external force acts on forced oscillator.

A simple pendulum of length 'l' carries a bob of mass 'm'. The bob is released from horizontal position. The tension in the string at the lowest point would be

A vertical U - tube of uniform cross - section contains water in both the arms. A 10 cm glycerine column (R.D. = 1.2) is added to one of the limbs. What is the level difference between the two free surface in the two limbs?

Establish Newton's third law from Newton's second law.

Two bodies of masses 10 kg and 20 kg respectively kept on a smooth, horizontal surface are tied to the ends of a light string. A horizontal force F = 600 N is applied to (i) A, (ii) B along the direction of string. What is the tension in the string in each case?

Which is greater , the attreaction of the earth ona1kg body or the attraction of the 1kg body on the earth ?

A moving shere P collides another shere Q at rest. If the collision takes place along the line joining their centres of mass such that their total kinetic energy is conserved and the fraction of K.E transferred by the colliding particle is 8"/"9, the ratio of mass of P and the mass of Q is

Water is flowing with a speed of 2 ms^(-1) in a horizontal pipe with cross-sectional area decreasing from 2 xx 10^(-2) m^(2) to 0.01 m^2 at pressure 4 xx 10^4 Pa. What will be the pressure at small cross-section ?

Why does a flag flutter when there is wind ?

Three sound waves of equal amplitude have frequencies (n-1), n, (n + 1). They superimpose to give beats. The number of beats produced per second will be ?

State the importance of work energy theorem .

A small sphere of mass 1 kg is rolling without slipping with linear speed v=sqrt((200)/(7)) m/s. It leaves the inclined plane at point C. The ration rotational and translational kinetic energy of the sphere when it strikes the ground after leaving from point C.

In case of a metal scale

A Carnot cycle has the reversible processes in the following order :

A block slides down a rough inclined plane of slope angle theta with a constant velocity. It is then projected up the same plane with an initial velocity v. The distance travelled by the block up the plane before coming to rest is

The two thigh bones (femurs),each of cross - sectional area 10cm^(2) supportthe upper part of a human body of mass 50kg Estimate the average pressure sustained by the femurs. (g=10ms^(-2)).

Figure shows the vibration of energy with the orbit radius r of satellite ina circular energy motion. Mark the correct statement.

A wheel rotating at angular speed of 20rads^(-1), is brought to rest by a constant torque in 4s. If the M.I is 0.2kgm^(2), the work done in first 2s is

The resultant of two forces whose magnitudes are in the ratio 3:5 is 28N. If the angle of their inclination is 60^(@), then find the magnitude of each force.

The first law of thermodynamics is concerned with the conservation of …………………… .

Let vec(A), vec(B) and vec(C ) be unit vectors. Suppose vec(A).vec(B) = vec(A).vec(C ) = 0 and that the angle between vec(B) and vec(C ) is (pi)/(6) " then " vec(A) = +- n[vec(B) xx vec(C )] find the n

Derive an expression for potential energy near the surface of the earth

The displacement of a particle varies according to the relation X=3 sin 100t+8 cos^(2)50t. Which of the following is//are correct about this motion.

Under the action of a force, a 3 kg body moves such that x= (t^2)/(2), where position x is in metre and t is in second. What is the work done by the force in first 3 second?

A body executes simple harmonic motion. The potential energy (PE), kinetic energy (KE) and total energy (TE) are measured as a function of displacement x. Which of the following statements is true ?

What will happen if the upper part of a ship is made heavier than its lower part?

When an angular momentum of the object will be zero?