50278 + Interview Questions in Physics

1.	Magnetic field associated with loop is given by graphs below. [Take anticlockwise current positive]
Answer» Magnetic field associated with loop is given by graphs below. [Take anticlockwise current positive]

Discussion

2.	A plank with a mass M= 6.00 kg rests on top of two identical solid cylindrical rollers that have R=5.00 cm and m=2.00 kg (figure). The plank is pulled by a constant horizontal force →F of magnitude 6.00 N applied to the end of the plank and perpendicular to the axes of the cylinders(which are parallel). The cylinders roll without slipping on a flat surface. There is also no slipping between the cylinders and the plank. All surfaces are rough. The initial acceleration of the plank at the moment when the rollers are equidistant from the ends of the plank is m/s2.
Answer» A plank with a mass $M = 6.00 k g$ rests on top of two identical solid cylindrical rollers that have $R = 5.00 c m$ and $m = 2.00 k g$ (figure). The plank is pulled by a constant horizontal force $\to F$ of magnitude $6.00$ $N$ applied to the end of the plank and perpendicular to the axes of the cylinders(which are parallel). The cylinders roll without slipping on a flat surface. There is also no slipping between the cylinders and the plank. All surfaces are rough. The initial acceleration of the plank at the moment when the rollers are equidistant from the ends of the plank is $m / s^{2}$ .

Discussion

3.	Two coherent sources emit light waves which superimpose at a point and are expressed as E1=E0sin(ωt+π/4)E2=2E0sin(ωt−π/4) 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 . The resultant intensity istimes I.
Answer» Two coherent sources emit light waves which superimpose at a point and are expressed as $\begin{matrix} E_{1} = E_{0} sin (ω t + π / 4) E_{2} = 2 E_{0} sin (ω t - π / 4) \end{matrix}$ 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 $E_{1}$ . The resultant intensity istimes $I$ .

Discussion

4.	A system consists of two idential cubes each of mass m linked together by a massless spring of spring constant k. The spring is compressed by x connecting cubes by thread. Find minimum value of x for which lower cube will bounce up after the thread has been burnt.
Answer» A system consists of two idential cubes each of mass $m$ linked together by a massless spring of spring constant $k$ . The spring is compressed by $x$ connecting cubes by thread. Find minimum value of $x$ for which lower cube will bounce up after the thread has been burnt.

Discussion

5.	Three point masses, each of mass are placed at the corners of an equilateral triangle of side l. Then the moment of inertia of this system about an axis along one side of the triangle is:
Answer» Three point masses, each of mass are placed at the corners of an equilateral triangle of side l. Then the moment of inertia of this system about an axis along one side of the triangle is:

Discussion

6.	A U-tube of base length ′l′ filled with the same volume of two liquids of densities ρ and 2ρ is moving with an acceleration ′a′ on the horizontal plane. If the height difference between the two surfaces ( open to atmosphere) becomes zero, then the height h is given by
Answer» A U-tube of base length $^{'} l^{'}$ filled with the same volume of two liquids of densities $ρ$ and $2 ρ$ is moving with an acceleration $^{'} a^{'}$ on the horizontal plane. If the height difference between the two surfaces ( open to atmosphere) becomes zero, then the height $h$ is given by

Discussion

7.	A bullet hits a stationary wooden block with a velocity of 200 m/s. After the collision, the bullet lodges into it and the combined mass move together with a velocity of 10 m/s. If the mass of the block is 9 kg, then find the mass of the bullet.
Answer» A bullet hits a stationary wooden block with a velocity of $200 m/s$ . After the collision, the bullet lodges into it and the combined mass move together with a velocity of $10 m/s$ . If the mass of the block is $9 kg$ , then find the mass of the bullet.

Discussion

8.	A stone of mass 1 kg is connected to a light inextensible string of length 2 m and the other end of the string is fixed. If the stone is moving in a vertical circular path, having a ratio of maximum velocity to the minimum velocity as 3. The value of kinetic energy at the bottommost point on the vertical circle is [Take g=10 m/s2]
Answer» A stone of mass $1 kg$ is connected to a light inextensible string of length $2 m$ and the other end of the string is fixed. If the stone is moving in a vertical circular path, having a ratio of maximum velocity to the minimum velocity as $3$ . The value of kinetic energy at the bottommost point on the vertical circle is [Take $g = 10 {m/s}^{2}]$

Discussion

9.	Consider the nuclear reaction A+B→C, and nuclei A and B are moving with kinetic energies of 5 MeV and 3 MeV respectively to form a nucleus C, which is in its excited state with excitation energy 10 MeV. If the K.E of C just after formation is x MeV, then the value of x is [Answer upto two decimal points] [Take mass of nuclei A, B and C are 25 Da, 10 Da and 34.995 Da respectively and 1 Da=930MeVc2]
Answer» Consider the nuclear reaction $A + B \to C$ , and nuclei $A$ and $B$ are moving with kinetic energies of 5 $M e V$ and 3 $M e V$ respectively to form a nucleus $C$ , which is in its excited state with excitation energy 10 $M e V$ . If the $K . E$ of $C$ just after formation is $x M e V$ , then the value of $x$ is [Answer upto two decimal points] [Take mass of nuclei $A$ , $B$ and $C$ are 25 $D a$ , 10 $D a$ and 34.995 $D a$ respectively and $1 D a = \frac{930 M e V}{c^{2}}$ ]

Discussion

10.	The figure shows mass m with velocity U. Ring is restricted to move on smooth fixed horizontal rod. The velocity of ring at that moment is :
Answer» The figure shows mass $m$ with velocity $U$ . Ring is restricted to move on smooth fixed horizontal rod. The velocity of ring at that moment is :

Discussion

11.	The ends of a stretched wire of length L are fixed at x = 0 and x = L. In one experiment the displacement of the wire is y1 = A sin (πxL) sinωt and energy is E1 and in another experiment its displacement is y2 = A sin(2πxL)sin 2 ωt and energy is E2. Then
Answer» The ends of a stretched wire of length $L$ are fixed at $x$ = 0 and $x$ = $L$ . In one experiment the displacement of the wire is $y_{1}$ = $A s i n (\frac{π x}{L}) s i n ω t$ and energy is $E_{1}$ and in another experiment its displacement is $y_{2}$ = $A s i n (\frac{2 π x}{L}) s i n 2 ω t$ and energy is $E_{2}$ . Then

Discussion

12.	If the frequency of sound produced by a siren increases from 400 Hz to 1200 Hz keeping the amplitude constant. The ratio of the intensity of sound produced at frequency 1200 Hz and 400 Hz will be
Answer» If the frequency of sound produced by a siren increases from $400 Hz$ to $1200 Hz$ keeping the amplitude constant. The ratio of the intensity of sound produced at frequency $1200 Hz$ and $400 Hz$ will be

Discussion

13.	In the figure, the velocities are in ground frame and the cylinder is performing pure rolling on the plank, velocity of point 'A' would be
Answer» In the figure, the velocities are in ground frame and the cylinder is performing pure rolling on the plank, velocity of point 'A' would be

13.

In the figure, the velocities are in ground frame and the cylinder is performing pure rolling on the plank, velocity of point 'A' would be

Answer»

In the figure, the velocities are in ground frame and the cylinder is performing pure rolling on the plank, velocity of point 'A' would be

Discussion

14.	What is a resistant body?
Answer» What is a resistant body?

Discussion

15.	How does light reflect?
Answer» How does light reflect?

Discussion

16.	An ideal gas at pressure 2.5×105 Pa and temperature 300 K occupies 100 cc. It is adiabatically compresses to half its original volume. Calculate (a) The final pressure (b) The final temperature and (c) The work done by the gas in the process. Take γ=1.5
Answer» An ideal gas at pressure $2.5 \times 10^{5}$ Pa and temperature 300 K occupies 100 cc. It is adiabatically compresses to half its original volume. Calculate (a) The final pressure (b) The final temperature and (c) The work done by the gas in the process. Take $γ = 1.5$

16.

An ideal gas at pressure 2.5×105 Pa and temperature 300 K occupies 100 cc. It is adiabatically compresses to half its original volume. Calculate (a) The final pressure (b) The final temperature and (c) The work done by the gas in the process. Take γ=1.5

Answer»

An ideal gas at pressure $2.5 \times 10^{5}$ Pa and temperature 300 K occupies 100 cc. It is adiabatically compresses to half its original volume. Calculate

(a) The final pressure

(b) The final temperature and

(c) The work done by the gas in the process. Take $γ = 1.5$

Discussion

17.	White light is incident normally on a glass plate (in air) of thickness 500 nm and refractive index of 1.5. The wavelength (in nm) in the visible region (400 nm - 700 nm) that is strongly reflected by the plate is:
Answer» White light is incident normally on a glass plate (in air) of thickness 500 nm and refractive index of 1.5. The wavelength (in nm) in the visible region (400 nm - 700 nm) that is strongly reflected by the plate is:

Discussion

18.	Calculate the least amount of work that must be done to freeze 1g of water at 0°C by means of refrigerator. Temperature of surroundings is 27°C. How much heat is passed into the surroundings?
Answer» Calculate the least amount of work that must be done to freeze 1g of water at 0°C by means of refrigerator. Temperature of surroundings is 27°C. How much heat is passed into the surroundings?

Discussion

19.	How many significant number are there in 0.0023040 ?
Answer» How many significant number are there in 0.0023040 ?

Discussion

20.	I was just thinking about the case, The whole cenario is in space there was an space craft it is attached to a mirror say 1.5 108 m below the space craft by many taut rods. Space craft is moving horizontally with high constant velocity. A person in space craft throws a ray of light to the attached mirror, velocity of light is 3108 m/sec. So time taken by ray of light to come back at initial position is 1sec. There was another observer w.r.t him ray of light follows a v-shaped path where the edge of v-shaped path is 1.5108 m below so each part of path must be greater then 1.5108 m this mean overall distance is increased ! So time taken also increased! Both person start as well as stop their stop watch simultaneously. But it read different time period how? What is happening here?
Answer» I was just thinking about the case, The whole cenario is in space there was an space craft it is attached to a mirror say 1.5 10⁸ m below the space craft by many taut rods. Space craft is moving horizontally with high constant velocity. A person in space craft throws a ray of light to the attached mirror, velocity of light is 310⁸m/sec. So time taken by ray of light to come back at initial position is 1sec. There was another observer w.r.t him ray of light follows a v-shaped path where the edge of v-shaped path is 1.510⁸ m below so each part of path must be greater then 1.510⁸ m this mean overall distance is increased ! So time taken also increased! Both person start as well as stop their stop watch simultaneously. But it read different time period how? What is happening here?

20.

I was just thinking about the case, The whole cenario is in space there was an space craft it is attached to a mirror say 1.5 108 m below the space craft by many taut rods. Space craft is moving horizontally with high constant velocity. A person in space craft throws a ray of light to the attached mirror, velocity of light is 3108 m/sec. So time taken by ray of light to come back at initial position is 1sec. There was another observer w.r.t him ray of light follows a v-shaped path where the edge of v-shaped path is 1.5108 m below so each part of path must be greater then 1.5108 m this mean overall distance is increased ! So time taken also increased! Both person start as well as stop their stop watch simultaneously. But it read different time period how? What is happening here?

Answer»

I was just thinking about the case,

The whole cenario is in space there was an space craft it is attached to a mirror say 1.5 *10⁸ m below the space craft by many taut rods. Space craft is moving horizontally with high constant velocity. A person in space craft throws a ray of light to the attached mirror, velocity of light is 3*10⁸m/sec. So time taken by ray of light to come back at initial position is 1sec.

There was another observer w.r.t him ray of light follows a v-shaped path where the edge of v-shaped path is 1.5*10⁸ m below so each part of path must be greater then 1.5*10⁸ m this mean overall distance is increased ! So time taken also increased!

Both person start as well as stop their stop watch simultaneously.

But it read different time period how?

What is happening here?

Discussion

21.	1) An electron and a proton having equal momentum, enter a uniform magnetic field at right angle to the field lines. What will be the ratio of their trajectories??
Answer» 1) An electron and a proton having equal momentum, enter a uniform magnetic field at right angle to the field lines. What will be the ratio of their trajectories??

Discussion

22.	Between the plates of parallel plate capacitor of capacitance C, two parallel plates, of the same material and area same as per the plate of the original capacitor, are placed. If the thickness of these plates is equal to 15th of the distance between the plates of the original capacitor, then the capacitance of the new capacitor is
Answer» Between the plates of parallel plate capacitor of capacitance C, two parallel plates, of the same material and area same as per the plate of the original capacitor, are placed. If the thickness of these plates is equal to ${\frac{1}{5}}^{t h}$ of the distance between the plates of the original capacitor, then the capacitance of the new capacitor is

Discussion

23.	if a bulb is connected in series with two bulbs parallels to each other which formula should I useto find which is more bright? why can't I use heat directly proportional to power and the relation of power in series and parallel? How do I know which relation to use in a question because heat is directly proportional to resistance in one formula and inversely proportional to it in other?
Answer» if a bulb is connected in series with two bulbs parallels to each other which formula should I useto find which is more bright? why can't I use heat directly proportional to power and the relation of power in series and parallel? How do I know which relation to use in a question because heat is directly proportional to resistance in one formula and inversely proportional to it in other?

Discussion

24.	A 1500-kg car moving o a flat, horizontal road negotiates a curve as show in figure. If the radius of the curve is 20.0 m and the coefficient of static friction between the tires and dry pavement is 0.50, find the maximum speed the car can have and still make the turn successfully.
Answer» A 1500-kg car moving o a flat, horizontal road negotiates a curve as show in figure. If the radius of the curve is 20.0 m and the coefficient of static friction between the tires and dry pavement is 0.50, find the maximum speed the car can have and still make the turn successfully.

Discussion

25.	A coil of area 100 cm^2 having 500 turns carries a current of 1 m A. It is suspended in a uniform magnetic field of induction 10^-3wb/m^2. Its plane making an angle of 60° with the lines of induction. the torque acting on the coil is
Answer» A coil of area 100 cm^2 having 500 turns carries a current of 1 m A. It is suspended in a uniform magnetic field of induction 10^-3wb/m^2. Its plane making an angle of 60° with the lines of induction. the torque acting on the coil is

Discussion

26.	The mass of the moon is 1/81 of earth's mass and its radius 1/4 that of earth. If the escape velocity from the earth's surface is 11.2 km/s ,its value for the moon...
Answer» The mass of the moon is 1/81 of earth's mass and its radius 1/4 that of earth. If the escape velocity from the earth's surface is 11.2 km/s ,its value for the moon...

Discussion

27.	there are two balls of 50kg and 10kg. They both are dropped of same height. They both are spherical iron balls(volumes are not same). air resistance is there. which ball will reach the ground first and why?
Answer» there are two balls of 50kg and 10kg. They both are dropped of same height. They both are spherical iron balls(volumes are not same). air resistance is there. which ball will reach the ground first and why?

Discussion

28.	The ratio between the height H of a mountain and the depth h of a mine if a simple pendulum swings with the same period at the top of the mountain and at the bottom of the mine is?
Answer» The ratio between the height H of a mountain and the depth h of a mine if a simple pendulum swings with the same period at the top of the mountain and at the bottom of the mine is?

Discussion

29.	a source of sound frequency 600 hz is placed inside water .the speed of sound in water is 1500m/s and in air is 300m/s.the frequency if sound recorded by an observer ,who is standing in air is.
Answer» a source of sound frequency 600 hz is placed inside water .the speed of sound in water is 1500m/s and in air is 300m/s.the frequency if sound recorded by an observer ,who is standing in air is.

Discussion

30.	Give 5 major characteristics of electromagnetic wave.
Answer» Give 5 major characteristics of electromagnetic wave.

Discussion

31.	A swimmer jumps from a bridge over a canal and swims 1 km upstream. After that first km, he passes a floating cork. He continues swimming for half an hour and then turns around swims back to the bridge. The swimmer and the cork reach the bridge at the same time. The swimmer has been swimming at a constant speed w.r.t water. If speed of water in canal is X km/hr., then X is
Answer» A swimmer jumps from a bridge over a canal and swims 1 km upstream. After that first km, he passes a floating cork. He continues swimming for half an hour and then turns around swims back to the bridge. The swimmer and the cork reach the bridge at the same time. The swimmer has been swimming at a constant speed w.r.t water. If speed of water in canal is X km/hr., then X is

Discussion

32.	In the figure the pulley P1 is fixed and the pulley P2 is movable. If W1=W2=100 N, what is the angle ∠AP2P1? The pulleys are frictionless.
Answer» In the figure the pulley $P_{1}$ is fixed and the pulley $P_{2}$ is movable. If $W_{1} = W_{2} = 100 N$ , what is the angle $∠ A P_{2} P_{1}$ ? The pulleys are frictionless.

Discussion

33.	The distance of a geostationary satellite from the centre of the earth(R=6400km) is nearest to
Answer» The distance of a geostationary satellite from the centre of the earth(R=6400km) is nearest to

Discussion

34.	A barometer having a cross - sectional area of 1.00 cm2 at sea level measures a pressure of 76.0 cm of Hg. The pressure exerted by this column of mercury is equal to the pressure exerted by the air on 1 cm2 of the earth's surface. The total mass of earth's atmosphere is___. (Average radius of earth is p km and density of mercury is 13.6 g/ml)
Answer» A barometer having a cross - sectional area of $1.00 c m^{2}$ at sea level measures a pressure of 76.0 cm of Hg. The pressure exerted by this column of mercury is equal to the pressure exerted by the air on $1 c m^{2}$ of the earth's surface. The total mass of earth's atmosphere is___. (Average radius of earth is p km and density of mercury is 13.6 g/ml)

Discussion

35.	A beaker of volume 140 cc. contains mercury so that the volume of the empty space above mercury is constant at all temperatures. What is the volume of mercury in cc in the beaker, if the linear coefficient of expansion of glass is 0.000009 K−1and the volume coefficient of mercury is 0.000189 K−1?.
Answer» A beaker of volume $140 c c$ . contains mercury so that the volume of the empty space above mercury is constant at all temperatures. What is the volume of mercury in cc in the beaker, if the linear coefficient of expansion of glass is $0.000009 K^{- 1}$ and the volume coefficient of mercury is $0.000189 K^{- 1}$ ?.

Discussion

36.	A circular plate of uniform thickness has a diameter of 28 cm. A circular portion of diameter 21 cm is removed from the plate as shown. Take the origin at the center of mass of the complete plate. The position of the center of mass of the remaining portion will shift towards left from the origin by
Answer» A circular plate of uniform thickness has a diameter of $28 cm$ . A circular portion of diameter $21 cm$ is removed from the plate as shown. Take the origin at the center of mass of the complete plate. The position of the center of mass of the remaining portion will shift towards left from the origin by

Discussion

37.	If α,β,γ are the roots of x3+px2+qx+r=0 , then (α- 1βγ) (β – 1γα) (γ – 1αβ) =
Answer» If α,β,γ are the roots of $x 3$ +p $x^{2}$ +qx+r=0 , then (α- $\frac{1}{β γ}$ ) (β – $\frac{1}{γ α}$ ) (γ – $\frac{1}{α β}$ ) =

Discussion

38.	In a Searle's experiment, the diameter of the wire as measured by a screw gauge with least count 0.001 cm is 0.050 cm. The length, measured by a scale of least count 0.1 cm, is 110.0 cm. When a weight of 50 N is suspended from the wire, the extension is measured to be 0.125 cm by a micrometer of least count 0.001 cm. Find the maximum error in the measurement of Young's modulus of the material of the wire from these data. y=WA×LX Where W is the weight suspended from the wire, A is the cross section area, L is the length and X is the extension in the wire. [IIT JEE 2004]
Answer» In a Searle's experiment, the diameter of the wire as measured by a screw gauge with least count 0.001 cm is 0.050 cm. The length, measured by a scale of least count 0.1 cm, is 110.0 cm. When a weight of 50 N is suspended from the wire, the extension is measured to be 0.125 cm by a micrometer of least count 0.001 cm. Find the maximum error in the measurement of Young's modulus of the material of the wire from these data. $y = \frac{W}{A} \times \frac{L}{X}$ Where W is the weight suspended from the wire, A is the cross section area, L is the length and X is the extension in the wire. [IIT JEE 2004]

38.

In a Searle's experiment, the diameter of the wire as measured by a screw gauge with least count 0.001 cm is 0.050 cm. The length, measured by a scale of least count 0.1 cm, is 110.0 cm. When a weight of 50 N is suspended from the wire, the extension is measured to be 0.125 cm by a micrometer of least count 0.001 cm. Find the maximum error in the measurement of Young's modulus of the material of the wire from these data. y=WA×LX Where W is the weight suspended from the wire, A is the cross section area, L is the length and X is the extension in the wire. [IIT JEE 2004]

Answer»

In a Searle's experiment, the diameter of the wire as measured by a screw gauge with least count 0.001 cm is 0.050 cm. The length, measured by a scale of least count 0.1 cm, is 110.0 cm. When a weight of 50 N is suspended from the wire, the extension is measured to be 0.125 cm by a micrometer of least count 0.001 cm. Find the maximum error in the measurement of Young's modulus of the material of the wire from these data.

$y = \frac{W}{A} \times \frac{L}{X}$
Where W is the weight suspended from the wire, A is the cross section area, L is the length and X is the extension in the wire.

[IIT JEE 2004]

Discussion

39.	A particle with a charge 2μC is hanging in air above a similarly charged conducting surface whose surface charge density is 43.3×10−12C/m2. The mass of particle is
Answer» A particle with a charge 2μC is hanging in air above a similarly charged conducting surface whose surface charge density is $43.3 \times 10^{- 12} C / m^{2}$ . The mass of particle is

Discussion

40.	A mass of 10 kg is moving with constant velocity 0.5 m/s parallel to x-axis. The shortest distance of the mass from the origin during its motion is 20 cm. What will be the angular momentum of the mass about the origin in SI unit?
Answer» A mass of 10 kg is moving with constant velocity 0.5 m/s parallel to x-axis. The shortest distance of the mass from the origin during its motion is 20 cm. What will be the angular momentum of the mass about the origin in SI unit?

Discussion

41.	A solid disc and a ring, both of radius 10 cm are placed on a horizontal table simultaneously, with initial angular speed equal to 10πrads−1. Which of the two will start to roll earlier? The co-efficient of kinetic friction is μk=0.2.
Answer» A solid disc and a ring, both of radius 10 cm are placed on a horizontal table simultaneously, with initial angular speed equal to $10 π r a d s^{- 1}$ . Which of the two will start to roll earlier? The co-efficient of kinetic friction is $μ_{k} = 0.2$ .

Discussion

42.	An earth satellite is moving around the earth in a circular orbit. In such case, what is conserved?
Answer» An earth satellite is moving around the earth in a circular orbit. In such case, what is conserved?

Discussion

43.	A voltage V=V0 sin ωt is applied to a series LCR circuit. Derive the expression for the average power dissipated over a cycle. Under what condition is (i) no power dissipated even though the current flows through the circuit, (ii) maximum power dissipated in the circuit?
Answer» A voltage $V = V_{0} s i n ω t$ is applied to a series LCR circuit. Derive the expression for the average power dissipated over a cycle. Under what condition is (i) no power dissipated even though the current flows through the circuit, (ii) maximum power dissipated in the circuit?

Discussion

44.	In the propagation of electromagnetic waves, the angle between the direction of propagation and plane of polarization is
Answer» In the propagation of electromagnetic waves, the angle between the direction of propagation and plane of polarization is

Discussion

45.	In 1.0 s, a particle goes from point A to point B, moving in a semicircle of radius 1.0 m (see figure). The magnitude of the average velocity is
Answer» In 1.0 s, a particle goes from point A to point B, moving in a semicircle of radius 1.0 m (see figure). The magnitude of the average velocity is

Discussion

46.	If →a is a collinear vector with →b=3^i+6^j+6^k and →a.→b=27. Then, →a is
Answer» If $\to a$ is a collinear vector with $\to b = 3^i + 6^j + 6^k$ and $\to a . \to b = 27$ . Then, $\to a$ is

Discussion

47.	A 50 kg boy stands on a platform spring scale in a lift that is going down with a constant speed 3 m/s. If the lift is brought to rest by a constant deceleration in a distance of 9 m, what does the scale read (in Newtons) during this period? (g=9.8 m/s2)
Answer» A 50 kg boy stands on a platform spring scale in a lift that is going down with a constant speed $3 m/s$ . If the lift is brought to rest by a constant deceleration in a distance of $9 m$ , what does the scale read (in Newtons) during this period? $(g = 9.8 {m/s}^{2})$

Discussion

48.	Rutherford's scattering experiment is related to the size of the
Answer» Rutherford's scattering experiment is related to the size of the

48.

Rutherford's scattering experiment is related to the size of the

Answer»

Rutherford's scattering experiment is related to the size of the

Discussion

49.	Two steel rods and an aluminium rod of equal length l0 and equal cross section are joined rigidly at their ends as shown in the figure below. All the rods are in a state of zero tension at 0∘ C. Find the length of the system when the temperature is raised to θ. Coefficient of linear expansion of aluminium and steel are αa and αs respectively. Young's modulus of aluminium is Ya and of steel is Ys. SteelAluminiumSteel
Answer» Two steel rods and an aluminium rod of equal length $l_{0}$ and equal cross section are joined rigidly at their ends as shown in the figure below. All the rods are in a state of zero tension at $0^{\circ} C$ . Find the length of the system when the temperature is raised to $θ$ . Coefficient of linear expansion of aluminium and steel are $α_{a}$ and $α_{s}$ respectively. Young's modulus of aluminium is $Y_{a}$ and of steel is $Y_{s}$ . $\begin{matrix} Steel Aluminium Steel \end{matrix}$

49.

Two steel rods and an aluminium rod of equal length l0 and equal cross section are joined rigidly at their ends as shown in the figure below. All the rods are in a state of zero tension at 0∘ C. Find the length of the system when the temperature is raised to θ. Coefficient of linear expansion of aluminium and steel are αa and αs respectively. Young's modulus of aluminium is Ya and of steel is Ys. SteelAluminiumSteel

Answer»

Two steel rods and an aluminium rod of equal length $l_{0}$ and equal cross section are joined rigidly at their ends as shown in the figure below. All the rods are in a state of zero tension at $0^{\circ} C$ . Find the length of the system when the temperature is raised to $θ$ . Coefficient of linear expansion of aluminium and steel are $α_{a}$ and $α_{s}$ respectively. Young's modulus of aluminium is $Y_{a}$ and of steel is $Y_{s}$ .

$\begin{matrix} Steel Aluminium Steel \end{matrix}$

Discussion

50.	A car of 800 kg negotiates a banked curve of radius 160 m on a smooth road. If the banking angle is 60∘, find the normal force between the tyres and the road. (g=10 m/s2)
Answer» A car of $800 k g$ negotiates a banked curve of radius $160 m$ on a smooth road. If the banking angle is $60^{\circ}$ , find the normal force between the tyres and the road. $(g = 10 m / s^{2})$

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

Magnetic field associated with loop is given by graphs below. [Take anticlockwise current positive]

A system consists of two idential cubes each of mass m linked together by a massless spring of spring constant k. The spring is compressed by x connecting cubes by thread. Find minimum value of x for which lower cube will bounce up after the thread has been burnt.

Three point masses, each of mass are placed at the corners of an equilateral triangle of side l. Then the moment of inertia of this system about an axis along one side of the triangle is:

A U-tube of base length ′l′ filled with the same volume of two liquids of densities ρ and 2ρ is moving with an acceleration ′a′ on the horizontal plane. If the height difference between the two surfaces ( open to atmosphere) becomes zero, then the height h is given by

A bullet hits a stationary wooden block with a velocity of 200 m/s. After the collision, the bullet lodges into it and the combined mass move together with a velocity of 10 m/s. If the mass of the block is 9 kg, then find the mass of the bullet.

The figure shows mass m with velocity U. Ring is restricted to move on smooth fixed horizontal rod. The velocity of ring at that moment is :

The ends of a stretched wire of length L are fixed at x = 0 and x = L. In one experiment the displacement of the wire is y1 = A sin (πxL) sinωt and energy is E1 and in another experiment its displacement is y2 = A sin(2πxL)sin 2 ωt and energy is E2. Then

If the frequency of sound produced by a siren increases from 400 Hz to 1200 Hz keeping the amplitude constant. The ratio of the intensity of sound produced at frequency 1200 Hz and 400 Hz will be

In the figure, the velocities are in ground frame and the cylinder is performing pure rolling on the plank, velocity of point 'A' would be

What is a resistant body?

How does light reflect?

An ideal gas at pressure 2.5×105 Pa and temperature 300 K occupies 100 cc. It is adiabatically compresses to half its original volume. Calculate (a) The final pressure (b) The final temperature and (c) The work done by the gas in the process. Take γ=1.5

White light is incident normally on a glass plate (in air) of thickness 500 nm and refractive index of 1.5. The wavelength (in nm) in the visible region (400 nm - 700 nm) that is strongly reflected by the plate is:

Calculate the least amount of work that must be done to freeze 1g of water at 0°C by means of refrigerator. Temperature of surroundings is 27°C. How much heat is passed into the surroundings?

How many significant number are there in 0.0023040 ?

1) An electron and a proton having equal momentum, enter a uniform magnetic field at right angle to the field lines. What will be the ratio of their trajectories??

A 1500-kg car moving o a flat, horizontal road negotiates a curve as show in figure. If the radius of the curve is 20.0 m and the coefficient of static friction between the tires and dry pavement is 0.50, find the maximum speed the car can have and still make the turn successfully.

A coil of area 100 cm^2 having 500 turns carries a current of 1 m A. It is suspended in a uniform magnetic field of induction 10^-3wb/m^2. Its plane making an angle of 60° with the lines of induction. the torque acting on the coil is

The mass of the moon is 1/81 of earth's mass and its radius 1/4 that of earth. If the escape velocity from the earth's surface is 11.2 km/s ,its value for the moon...

there are two balls of 50kg and 10kg. They both are dropped of same height. They both are spherical iron balls(volumes are not same). air resistance is there. which ball will reach the ground first and why?

The ratio between the height H of a mountain and the depth h of a mine if a simple pendulum swings with the same period at the top of the mountain and at the bottom of the mine is?

a source of sound frequency 600 hz is placed inside water .the speed of sound in water is 1500m/s and in air is 300m/s.the frequency if sound recorded by an observer ,who is standing in air is.

Give 5 major characteristics of electromagnetic wave.

In the figure the pulley P1 is fixed and the pulley P2 is movable. If W1=W2=100 N, what is the angle ∠AP2P1? The pulleys are frictionless.

The distance of a geostationary satellite from the centre of the earth(R=6400km) is nearest to

A circular plate of uniform thickness has a diameter of 28 cm. A circular portion of diameter 21 cm is removed from the plate as shown. Take the origin at the center of mass of the complete plate. The position of the center of mass of the remaining portion will shift towards left from the origin by

If α,β,γ are the roots of x3+px2+qx+r=0 , then (α- 1βγ) (β – 1γα) (γ – 1αβ) =

A particle with a charge 2μC is hanging in air above a similarly charged conducting surface whose surface charge density is 43.3×10−12C/m2. The mass of particle is

A mass of 10 kg is moving with constant velocity 0.5 m/s parallel to x-axis. The shortest distance of the mass from the origin during its motion is 20 cm. What will be the angular momentum of the mass about the origin in SI unit?

A solid disc and a ring, both of radius 10 cm are placed on a horizontal table simultaneously, with initial angular speed equal to 10πrads−1. Which of the two will start to roll earlier? The co-efficient of kinetic friction is μk=0.2.

An earth satellite is moving around the earth in a circular orbit. In such case, what is conserved?

A voltage V=V0 sin ωt is applied to a series LCR circuit. Derive the expression for the average power dissipated over a cycle. Under what condition is (i) no power dissipated even though the current flows through the circuit, (ii) maximum power dissipated in the circuit?

In the propagation of electromagnetic waves, the angle between the direction of propagation and plane of polarization is

In 1.0 s, a particle goes from point A to point B, moving in a semicircle of radius 1.0 m (see figure). The magnitude of the average velocity is

If →a is a collinear vector with →b=3^i+6^j+6^k and →a.→b=27. Then, →a is

A 50 kg boy stands on a platform spring scale in a lift that is going down with a constant speed 3 m/s. If the lift is brought to rest by a constant deceleration in a distance of 9 m, what does the scale read (in Newtons) during this period? (g=9.8 m/s2)

Rutherford's scattering experiment is related to the size of the

A car of 800 kg negotiates a banked curve of radius 160 m on a smooth road. If the banking angle is 60∘, find the normal force between the tyres and the road. (g=10 m/s2)