50278 + Interview Questions in Physics

1.	Does it matter if one uses have instead of absolute pressure in applying Bernoulli's equation? Explain
Answer» Does it matter if one uses have instead of absolute pressure in applying Bernoulli's equation? Explain

Discussion

2.	These are three pots and four coins. All these coins are to be distributed into these pots where any pot can contain any number of coins. Column1Column2(A)The number of ways in which all these coins can be(P)3distributed if all coins are identical but all pots are different(B)The number of ways in which all these coins can be(Q)6distributed if all coins are different but all pots are identical(C)The number of ways all these coins can be distributed such(R)15that no pot is empty if all coins are different but all pots areidentical.(D)The number of ways all these coins can be distributed(S)14such that no pot is empty is all coins are identical but all pots are different.
Answer» These are three pots and four coins. All these coins are to be distributed into these pots where any pot can contain any number of coins. $\begin{matrix} C o l u m n 1 & C o l u m n 2 (A) & T h e n u m b e r o f w a y s i n w h i c h a l l t h e s e c o i n s c a n b e & (P) & 3 d i s t r i b u t e d i f a l l c o i n s a r e i d e n t i c a l b u t a l l p o t s a r e d i f f e r e n t (B) & T h e n u m b e r o f w a y s i n w h i c h a l l t h e s e c o i n s c a n b e & (Q) & 6 d i s t r i b u t e d i f a l l c o i n s a r e d i f f e r e n t b u t a l l p o t s a r e i d e n t i c a l (C) & T h e n u m b e r o f w a y s a l l t h e s e c o i n s c a n b e d i s t r i b u t e d s u c h & (R) & 15 t h a t n o p o t i s e m p t y i f a l l c o i n s a r e d i f f e r e n t b u t a l l p o t s a r e i d e n t i c a l . (D) & T h e n u m b e r o f w a y s a l l t h e s e c o i n s c a n b e d i s t r i b u t e d & (S) & 14 s u c h t h a t n o p o t i s e m p t y i s a l l c o i n s a r e i d e n t i c a l b u t a l l p o t s a r e d i f f e r e n t . \end{matrix}$

2.

These are three pots and four coins. All these coins are to be distributed into these pots where any pot can contain any number of coins. Column1Column2(A)The number of ways in which all these coins can be(P)3distributed if all coins are identical but all pots are different(B)The number of ways in which all these coins can be(Q)6distributed if all coins are different but all pots are identical(C)The number of ways all these coins can be distributed such(R)15that no pot is empty if all coins are different but all pots areidentical.(D)The number of ways all these coins can be distributed(S)14such that no pot is empty is all coins are identical but all pots are different.

Answer»

These are three pots and four coins. All these coins are to be distributed into these pots where any pot can contain any number of coins.

$\begin{matrix} C o l u m n 1 & C o l u m n 2 (A) & T h e n u m b e r o f w a y s i n w h i c h a l l t h e s e c o i n s c a n b e & (P) & 3 d i s t r i b u t e d i f a l l c o i n s a r e i d e n t i c a l b u t a l l p o t s a r e d i f f e r e n t (B) & T h e n u m b e r o f w a y s i n w h i c h a l l t h e s e c o i n s c a n b e & (Q) & 6 d i s t r i b u t e d i f a l l c o i n s a r e d i f f e r e n t b u t a l l p o t s a r e i d e n t i c a l (C) & T h e n u m b e r o f w a y s a l l t h e s e c o i n s c a n b e d i s t r i b u t e d s u c h & (R) & 15 t h a t n o p o t i s e m p t y i f a l l c o i n s a r e d i f f e r e n t b u t a l l p o t s a r e i d e n t i c a l . (D) & T h e n u m b e r o f w a y s a l l t h e s e c o i n s c a n b e d i s t r i b u t e d & (S) & 14 s u c h t h a t n o p o t i s e m p t y i s a l l c o i n s a r e i d e n t i c a l b u t a l l p o t s a r e d i f f e r e n t . \end{matrix}$

Discussion

3.	Show that the altitude of the right circular cone of maximum volume that can be inscribed in a sphere of radius r is 4r3. Also,show that the maximum volume of the cone is 827 of the volume of the sphere.
Answer» Show that the altitude of the right circular cone of maximum volume that can be inscribed in a sphere of radius r is $\frac{4 r}{3}$ . Also,show that the maximum volume of the cone is $\frac{8}{27}$ of the volume of the sphere.

Discussion

4.	In a Young's double slit experiment, a sheet of thickness 100 µm and refractive index 1.5 is introduced as shown in the figure. A sheet of thickness t and refractive index 2 is introduced in lower ray's path. It is observed that there is no displacement in the fringes. The value of t is
Answer» In a Young's double slit experiment, a sheet of thickness 100 µm and refractive index $1.5$ is introduced as shown in the figure. A sheet of thickness t and refractive index $2$ is introduced in lower ray's path. It is observed that there is no displacement in the fringes. The value of $t$ is

Discussion

5.	A solid hemisphere of radius R is placed on an inclined plane of inclination θ. What will be the maximum value of θ for which the hemisphere will not topple? (Assume that the solid hemisphere will not slide)
Answer» A solid hemisphere of radius $R$ is placed on an inclined plane of inclination $θ .$ What will be the maximum value of $θ$ for which the hemisphere will not topple? (Assume that the solid hemisphere will not slide)

Discussion

6.	"choke is used to cut currents with minimal power loss" is this statement even true? Considering the fact that when power factor is unity it has less line loss, a choke seems to only create more power loss by decreasing the power factor? Or does choke have no relation to power factor?
Answer» "choke is used to cut currents with minimal power loss" is this statement even true? Considering the fact that when power factor is unity it has less line loss, a choke seems to only create more power loss by decreasing the power factor? Or does choke have no relation to power factor?

Discussion

7.	If and are the wave length (in A∘) of x - rays and infra red radiations respectively, then the relation between them is
Answer» If and are the wave length (in $A^{\circ})$ of x - rays and infra red radiations respectively, then the relation between them is

Discussion

8.	Two bodies of equal masses revolve in circular orbits of radii R1 and R2 with the same period. Their centripetal forces are in the ratio
Answer» Two bodies of equal masses revolve in circular orbits of radii $R_{1}$ and $R_{2}$ with the same period. Their centripetal forces are in the ratio

Discussion

9.	A magnet of magnetic moment 50^iA−m2 is placed along the x - axis in a magnetic field →B=(0.5^i+3.0^j)T.The torque acting on the magnet is
Answer» A magnet of magnetic moment $50^i A - m^{2}$ is placed along the x - axis in a magnetic field $\to B = (0.5^i + 3.0^j) T$ .The torque acting on the magnet is

Discussion

10.	A rifle bullet loses 1/20th of its velocity in passing through a plank. The least number of such planks required just to stop the bullet is
Answer» A rifle bullet loses $1 / 20^{t h}$ of its velocity in passing through a plank. The least number of such planks required just to stop the bullet is

10.

A rifle bullet loses 1/20th of its velocity in passing through a plank. The least number of such planks required just to stop the bullet is

Answer»

A rifle bullet loses $1 / 20^{t h}$ of its velocity in passing through a plank. The least number of such planks required just to stop the bullet is

Discussion

11.	A drop of liquid of diameter 2.8 mm breaks up into 125 identical drops. The change in energy is nearly (S.T. of liquid =75 dynes/cm)
Answer» A drop of liquid of diameter 2.8 mm breaks up into 125 identical drops. The change in energy is nearly (S.T. of liquid =75 dynes/cm)

11.

A drop of liquid of diameter 2.8 mm breaks up into 125 identical drops. The change in energy is nearly (S.T. of liquid =75 dynes/cm)

Answer»

A drop of liquid of diameter 2.8 mm breaks up into 125 identical drops.

The change in energy is nearly (S.T. of liquid =75 dynes/cm)

Discussion

12.	Three identical small ball each of mass m=1 kg and Q=10−4C are connected by insulating string of length L=1 m and are placed on frictionless horizontal surface as shown in figure. Middle ball B is given velocity V=10 m/s, then minimum seperation between ball A and C can be
Answer» Three identical small ball each of mass m=1 kg and $Q = 10^{- 4} C$ are connected by insulating string of length L=1 m and are placed on frictionless horizontal surface as shown in figure. Middle ball B is given velocity V=10 m/s, then minimum seperation between ball A and C can be

Discussion

13.	Two capillary tube of radius r1 and r2 are put vertically one each in two liquids whose relative densities are 0.6 and 0.4 and surface tension are 60 dyne/cm and 50 dyne/cm respectively. If ratio of heights of liquid in two tube is 8:10 respectively. Find r1r2. (Assume contact angle is same in both case)
Answer» Two capillary tube of radius $r_{1}$ and $r_{2}$ are put vertically one each in two liquids whose relative densities are $0.6$ and $0.4$ and surface tension are $60 dyne/cm$ and $50 dyne/cm$ respectively. If ratio of heights of liquid in two tube is $8 : 10$ respectively. Find $\frac{r_{1}}{r_{2}}$ . (Assume contact angle is same in both case)

Discussion

14.	Use Biot-Savart law to derive the expression for the magnetic field on the axis of a current carrying circular loop of radius R. Draw the magnetic field lines due to a circular wire carrying current I.
Answer» Use Biot-Savart law to derive the expression for the magnetic field on the axis of a current carrying circular loop of radius R. Draw the magnetic field lines due to a circular wire carrying current I.

Discussion

15.	How could we know about that: Acceleration's unit is m/s2 Velocity's unit is m/s.
Answer» How could we know about that: Acceleration's unit is m/s² ^{Velocity's unit is m/s.}

15.

How could we know about that: Acceleration's unit is m/s2 Velocity's unit is m/s.

Answer»

How could we know about that:

Acceleration's unit is m/s²

^{Velocity's unit is m/s.}

Discussion

16.	A container made up of insulating material contains 4 moles of an ideal diatomic gas at temperature T. Heat Q is supplied to this gas, due to which 2 moles of the gas are dissociated into atoms, but the temperature of the gas remains constant. Find the option that correctly represents the relation between Q and T.
Answer» A container made up of insulating material contains 4 moles of an ideal diatomic gas at temperature $T$ . Heat $Q$ is supplied to this gas, due to which 2 moles of the gas are dissociated into atoms, but the temperature of the gas remains constant. Find the option that correctly represents the relation between $Q$ and $T$ .

Discussion

17.	Describe fully diffraction of light at a single slit by deriving formula and explaining each step with reasons.Explain deeply about minima and maxima and also tell about primary and secondary minima and maxima.
Answer» Describe fully diffraction of light at a single slit by deriving formula and explaining each step with reasons.Explain deeply about minima and maxima and also tell about primary and secondary minima and maxima.

Discussion

18.	Find the expression of time period, velocity, frequency of charged particle when it enters perpendicular to the direction of magnetic field. (Circular path).
Answer» Find the expression of time period, velocity, frequency of charged particle when it enters perpendicular to the direction of magnetic field. (Circular path).

Discussion

19.	Right end of the string is attached to a light frictionless ring which can freely move on a vertical rod. A wave pulse is sent on the string from left propagating with speed 2.5 cm/s. Initially, the centre of pulse is 5 cm apart from the ring. At, t=2 s, the shape of string can be given as
Answer» Right end of the string is attached to a light frictionless ring which can freely move on a vertical rod. A wave pulse is sent on the string from left propagating with speed $2.5 cm/s$ . Initially, the centre of pulse is $5 cm$ apart from the ring. At, $t = 2 s$ , the shape of string can be given as

Discussion

20.	A railroad car is moving I the +x direction on a straight and level track. A person in the railroad car throws a ball. The ball follows trajectory shown, relative to the railroad car. From an inspection of the trajectory, what can be concluded about the motion of railroad car? Treat y-axis along vertical.
Answer» A railroad car is moving I the +x direction on a straight and level track. A person in the railroad car throws a ball. The ball follows trajectory shown, relative to the railroad car. From an inspection of the trajectory, what can be concluded about the motion of railroad car? Treat y-axis along vertical.

20.

A railroad car is moving I the +x direction on a straight and level track. A person in the railroad car throws a ball. The ball follows trajectory shown, relative to the railroad car. From an inspection of the trajectory, what can be concluded about the motion of railroad car? Treat y-axis along vertical.

Answer»

A railroad car is moving I the +x direction on a straight and level track. A person in the railroad car throws a ball. The ball follows trajectory shown, relative to the railroad car. From an inspection of the trajectory, what can be concluded about the motion of railroad car? Treat y-axis along vertical.

Discussion

21.	What is difference between plasticity and perfect inelastic body?
Answer» What is difference between plasticity and perfect inelastic body?

Discussion

22.	Three charges +4Q,Q and q is placed in a straight line of lenth l at points 0,l/2and l distance away from one end respectively.What should be Q in order to make the net force on q to be zero?
Answer» Three charges +4Q,Q and q is placed in a straight line of lenth l at points 0,l/2and l distance away from one end respectively.What should be Q in order to make the net force on q to be zero?

Discussion

23.	The plots of intensity versus wavelength for three black bodies at temperatures T1,T2 and T3 respectively are as shown. Their temperature are such that
Answer» The plots of intensity versus wavelength for three black bodies at temperatures $T_{1}, T_{2} a n d T_{3}$ respectively are as shown. Their temperature are such that

Discussion

24.	A body of 2 kg has an initial speed 5ms–1. A force acts on it for some time in the direction of motion. The force time graph is shown in figure. The final speed of the body.
Answer» A body of 2 kg has an initial speed $5 m s^{- 1} .$ A force acts on it for some time in the direction of motion. The force time graph is shown in figure. The final speed of the body.

Discussion

25.	In a series LCR circuit L = 10 mH, C = 1 μ F and R = 3Ω. It is connected to an AC voltage source. The inductive reactance of the circuit at a frequency 25% less than resonant frequency is
Answer» In a series LCR circuit L = 10 mH, C = 1 $μ$ F and R = 3 $Ω$ . It is connected to an AC voltage source. The inductive reactance of the circuit at a frequency 25% less than resonant frequency is

Discussion

26.	N resistors each of resistance R are first combined to get minimum possible resistance and then combined to get maximum possible resistance. The ratio of the minimum to maximum resistance is
Answer» N resistors each of resistance R are first combined to get minimum possible resistance and then combined to get maximum possible resistance. The ratio of the minimum to maximum resistance is

Discussion

27.	Find the centre of mass of a uniform plate having semicircular inner and outer boundaries of radii R1 and R2 (figure 9-E5).
Answer» Find the centre of mass of a uniform plate having semicircular inner and outer boundaries of radii $R_{1}$ and $R_{2}$ (figure 9-E5).

27.

Find the centre of mass of a uniform plate having semicircular inner and outer boundaries of radii R1 and R2 (figure 9-E5).

Answer»

Find the centre of mass of a uniform plate having semicircular inner and outer boundaries of radii $R_{1}$ and $R_{2}$ (figure 9-E5).

Discussion

28.	The pulleys and strings shown in the figure are smooth and of negligible mass. For the system to remain in equilibrium, the angle θ should be:
Answer» The pulleys and strings shown in the figure are smooth and of negligible mass. For the system to remain in equilibrium, the angle $θ$ should be:

Discussion

29.	If α denotes the coefficient of linear expansion of a block , L denotes length of the block and T denotes temperature, then which one of the following options is true?
Answer» If $α$ denotes the coefficient of linear expansion of a block , $L$ denotes length of the block and $T$ denotes temperature, then which one of the following options is true?

Discussion

30.	A traffic policeman sounds a whistle to stop a car-driver approaching towards him. The car-driver does not stop and takes the plea in court that because of the Doppler shift, the frequency of the whistle reaching him might have gone beyond the audible limit of 20 kHz and he did not hear it. Experiments showed that the whistle emits a sound with frequency close to 16 kHz. Assuming that the claim of the driver is true, how fast was he driving the car ? Take the speed of sound in air to be 330ms−1. Is this speed practical with today's technology ?
Answer» A traffic policeman sounds a whistle to stop a car-driver approaching towards him. The car-driver does not stop and takes the plea in court that because of the Doppler shift, the frequency of the whistle reaching him might have gone beyond the audible limit of 20 kHz and he did not hear it. Experiments showed that the whistle emits a sound with frequency close to 16 kHz. Assuming that the claim of the driver is true, how fast was he driving the car ? Take the speed of sound in air to be $330 m s^{- 1}$ . Is this speed practical with today's technology ?

Discussion

31.	The potential energy of particle of mass 'm' is given by U=12kx2 for x<0 and U = 0 for x ≥ 0. If total mechanical energy of the particle is E. Then its speed at x=√2Ek is
Answer» The potential energy of particle of mass 'm' is given by $U = \frac{1}{2} k x^{2}$ for x<0 and U = 0 for x $\geq$ 0. If total mechanical energy of the particle is E. Then its speed at $x = \sqrt{\frac{2 E}{k}}$ is

Discussion

32.	Two gases occupy two containers A and B. The gas in A, of volume 0.10 m3, exerts a pressure of 1.40 MPa and that in B, of volume 0.15 m3, exerts a pressure of 0.7 MPa. The two containers are joined by a tube of negligible volume and the gases are allowed to intermingle. Then, if the temperature remains constant, the final pressure in the containers will be ( in MPa):
Answer» Two gases occupy two containers A and B. The gas in A, of volume $0.10 m^{3}$ , exerts a pressure of $1.40 MPa$ and that in B, of volume $0.15 m^{3}$ , exerts a pressure of $0.7 MPa$ . The two containers are joined by a tube of negligible volume and the gases are allowed to intermingle. Then, if the temperature remains constant, the final pressure in the containers will be $(in MPa)$ :

Discussion

33.	Where will a body weigh more 1 km above the surface of the earth or 1 km below the surface of the earth?
Answer» Where will a body weigh more 1 km above the surface of the earth or 1 km below the surface of the earth?

Discussion

34.	Two thin convex lenses of focal length f1and f2 are separated by a horizontal distance d (where d<f1,d<f2) and their centers are displaced by a vertical separation Δ as shown in figure. Taking the origin of coordinates O at the center of the first lens, the x and y coordinates of the focal point of this lens system, for a parallel beam of rays coming from the left, are given by:
Answer» Two thin convex lenses of focal length $f_{1} a n d f_{2}$ are separated by a horizontal distance d (where $d < f_{1}, d < f_{2}$ ) and their centers are displaced by a vertical separation $Δ$ as shown in figure. Taking the origin of coordinates O at the center of the first lens, the x and y coordinates of the focal point of this lens system, for a parallel beam of rays coming from the left, are given by:

Discussion

35.	If i push a block with 10N force,the block moves ahead. According to Newton's third law the block also exerts equal amount of force on me.So how the block moves ahead?
Answer» If i push a block with 10N force,the block moves ahead. According to Newton's third law the block also exerts equal amount of force on me.So how the block moves ahead?

Discussion

36.	why do fitzgerald contraction occur/
Answer» why do fitzgerald contraction occur/

Discussion

37.	In a triangle ABC, ∠B=90∘ and a+b=4. The area of the triangle is maximum when ∠C is
Answer» In a triangle ABC, $∠ B = 90^{\circ}$ and $a + b = 4.$ The area of the triangle is maximum when $∠ C$ is

Discussion

38.	What are the limitations of cyclotron
Answer» What are the limitations of cyclotron

Discussion

39.	Three negative point charges - q each, and three positive point charges + q. + q and + Q are placed at the vertices of a regular hexagon as shown in Fig. 20.16. For what value of Q will the electric field at centre O due to the five charges at A, B, D, E and F be twice the electric field at centre O due to charge Q at C alone?
Answer» Three negative point charges - q each, and three positive point charges + q. + q and + Q are placed at the vertices of a regular hexagon as shown in Fig. 20.16. For what value of Q will the electric field at centre O due to the five charges at A, B, D, E and F be twice the electric field at centre O due to charge Q at C alone?

Discussion

40.	Suppose while sitting in a parked car, you notice a jogger approaching towards you in the side view mirror of R= 2m. If the jogger is running at a speed of 5ms-1 , how fast the image of the jogger appear to move when the jogger is 39m away?
Answer» Suppose while sitting in a parked car, you notice a jogger approaching towards you in the side view mirror of R= 2m. If the jogger is running at a speed of 5ms^-1 , how fast the image of the jogger appear to move when the jogger is 39m away?

Discussion

41.	A ball is in a hot air balloon that starts from rest at t = 0 and accelerates upwards at 2m/s2. After 10s, the ball is dropped from the balloon Draw the a-t graph of the ball from t = θ
Answer» A ball is in a hot air balloon that starts from rest at t = 0 and accelerates upwards at 2m/s². After 10s, the ball is dropped from the balloon Draw the a-t graph of the ball from t = $θ$

41.

A ball is in a hot air balloon that starts from rest at t = 0 and accelerates upwards at 2m/s2. After 10s, the ball is dropped from the balloon Draw the a-t graph of the ball from t = θ

Answer»

A ball is in a hot air balloon that starts from rest at t = 0 and accelerates upwards at 2m/s². After 10s, the ball is dropped from the balloon

Draw the a-t graph of the ball from t = $θ$

Discussion

42.	What is the meaning of magnitude?
Answer» What is the meaning of magnitude?

Discussion

43.	The isotope 125B having a mass 12.014 u undergoes β -decay to 126C , 126C has an excited state of the nucleus (125C∗ ) at 4.041 MeV above its ground state. If 125B decays to 126C∗, the maximum kinetic energy of the β-particle in units of MeV is(1 u=931.5MeV/c2, where c is the speed of light in vacuum).
Answer» The isotope $_{5}^{12} B$ having a mass 12.014 u undergoes $β$ -decay to $_{6}^{12} C$ , $_{6}^{12} C$ has an excited state of the nucleus ( $_{5}^{12} C^{}$ ) at $4.041 M e V$ above its ground state. If $_{5}^{12} B$ decays to $_{6}^{12} C^{}$ , the maximum kinetic energy of the $β$ -particle in units of $M e V$ is ( $1 u = 931.5 M e V / c^{2}$ , where c is the speed of light in vacuum).

Discussion

44.	Figure shows a vessel partitioned by a fixed diathermic separation. Different ideal gases are filled in the two parts. The rms speed of the molecules in the left pat equals the mean speed of the molecules in the right part. Calculate the ratio of the mass of a molecule in the left part to the mass of a molecule in the right part.
Answer» Figure shows a vessel partitioned by a fixed diathermic separation. Different ideal gases are filled in the two parts. The rms speed of the molecules in the left pat equals the mean speed of the molecules in the right part. Calculate the ratio of the mass of a molecule in the left part to the mass of a molecule in the right part.

Discussion

45.	Define the focal plane of a Spherical Mirror.
Answer» Define the focal plane of a Spherical Mirror.

Discussion

46.	Using differentials, find the approximate value of the following up to 3 places of decimal. (15)14
Answer» Using differentials, find the approximate value of the following up to 3 places of decimal. $(15)^{\frac{1}{4}}$

Discussion

47.	To keep valuable instruments away from the earth's magnetic field, they are enclosed in iron boxes. Explain.
Answer» To keep valuable instruments away from the earth's magnetic field, they are enclosed in iron boxes. Explain.

Discussion

48.	define the counter current mechanism.
Answer» define the counter current mechanism.

Discussion

49.	Partial charges are involved in:
Answer» Partial charges are involved in:

Discussion

50.	Two cars are moving on two perpendicular roads towards a crossing with uniform speeds of 72 km/hr and 36 km/hr. If first car blows horn of frequency 280 Hz, then the frequency of horn heard by the driver of second car when line joining the cars make 45∘ angle with the roads; will be
Answer» Two cars are moving on two perpendicular roads towards a crossing with uniform speeds of 72 km/hr and 36 km/hr. If first car blows horn of frequency 280 Hz, then the frequency of horn heard by the driver of second car when line joining the cars make $45^{\circ}$ angle with the roads; will be

50.

Two cars are moving on two perpendicular roads towards a crossing with uniform speeds of 72 km/hr and 36 km/hr. If first car blows horn of frequency 280 Hz, then the frequency of horn heard by the driver of second car when line joining the cars make 45∘ angle with the roads; will be

Answer»

Two cars are moving on two perpendicular roads towards a crossing with uniform speeds of 72 km/hr and 36 km/hr. If first car blows horn of frequency 280 Hz, then the frequency of horn heard by the driver of second car when line joining the cars make $45^{\circ}$ angle with the roads; will be

Discussion

Explore topic-wise InterviewSolutions in Current Affairs.

Does it matter if one uses have instead of absolute pressure in applying Bernoulli's equation? Explain

Show that the altitude of the right circular cone of maximum volume that can be inscribed in a sphere of radius r is 4r3. Also,show that the maximum volume of the cone is 827 of the volume of the sphere.

In a Young's double slit experiment, a sheet of thickness 100 µm and refractive index 1.5 is introduced as shown in the figure. A sheet of thickness t and refractive index 2 is introduced in lower ray's path. It is observed that there is no displacement in the fringes. The value of t is

A solid hemisphere of radius R is placed on an inclined plane of inclination θ. What will be the maximum value of θ for which the hemisphere will not topple? (Assume that the solid hemisphere will not slide)

"choke is used to cut currents with minimal power loss" is this statement even true? Considering the fact that when power factor is unity it has less line loss, a choke seems to only create more power loss by decreasing the power factor? Or does choke have no relation to power factor?

If and are the wave length (in A∘) of x - rays and infra red radiations respectively, then the relation between them is

Two bodies of equal masses revolve in circular orbits of radii R1 and R2 with the same period. Their centripetal forces are in the ratio

A magnet of magnetic moment 50^iA−m2 is placed along the x - axis in a magnetic field →B=(0.5^i+3.0^j)T.The torque acting on the magnet is

A rifle bullet loses 1/20th of its velocity in passing through a plank. The least number of such planks required just to stop the bullet is

A drop of liquid of diameter 2.8 mm breaks up into 125 identical drops. The change in energy is nearly (S.T. of liquid =75 dynes/cm)

Three identical small ball each of mass m=1 kg and Q=10−4C are connected by insulating string of length L=1 m and are placed on frictionless horizontal surface as shown in figure. Middle ball B is given velocity V=10 m/s, then minimum seperation between ball A and C can be

Use Biot-Savart law to derive the expression for the magnetic field on the axis of a current carrying circular loop of radius R. Draw the magnetic field lines due to a circular wire carrying current I.

How could we know about that: Acceleration's unit is m/s2 Velocity's unit is m/s.

Describe fully diffraction of light at a single slit by deriving formula and explaining each step with reasons.Explain deeply about minima and maxima and also tell about primary and secondary minima and maxima.

Find the expression of time period, velocity, frequency of charged particle when it enters perpendicular to the direction of magnetic field. (Circular path).

Right end of the string is attached to a light frictionless ring which can freely move on a vertical rod. A wave pulse is sent on the string from left propagating with speed 2.5 cm/s. Initially, the centre of pulse is 5 cm apart from the ring. At, t=2 s, the shape of string can be given as

What is difference between plasticity and perfect inelastic body?

Three charges +4Q,Q and q is placed in a straight line of lenth l at points 0,l/2and l distance away from one end respectively.What should be Q in order to make the net force on q to be zero?

The plots of intensity versus wavelength for three black bodies at temperatures T1,T2 and T3 respectively are as shown. Their temperature are such that

A body of 2 kg has an initial speed 5ms–1. A force acts on it for some time in the direction of motion. The force time graph is shown in figure. The final speed of the body.

In a series LCR circuit L = 10 mH, C = 1 μ F and R = 3Ω. It is connected to an AC voltage source. The inductive reactance of the circuit at a frequency 25% less than resonant frequency is

N resistors each of resistance R are first combined to get minimum possible resistance and then combined to get maximum possible resistance. The ratio of the minimum to maximum resistance is

Find the centre of mass of a uniform plate having semicircular inner and outer boundaries of radii R1 and R2 (figure 9-E5).

The pulleys and strings shown in the figure are smooth and of negligible mass. For the system to remain in equilibrium, the angle θ should be:

If α denotes the coefficient of linear expansion of a block , L denotes length of the block and T denotes temperature, then which one of the following options is true?

The potential energy of particle of mass 'm' is given by U=12kx2 for x&lt;0 and U = 0 for x ≥ 0. If total mechanical energy of the particle is E. Then its speed at x=√2Ek is

Where will a body weigh more 1 km above the surface of the earth or 1 km below the surface of the earth?

If i push a block with 10N force,the block moves ahead. According to Newton's third law the block also exerts equal amount of force on me.So how the block moves ahead?

why do fitzgerald contraction occur/

In a triangle ABC, ∠B=90∘ and a+b=4. The area of the triangle is maximum when ∠C is

What are the limitations of cyclotron

Suppose while sitting in a parked car, you notice a jogger approaching towards you in the side view mirror of R= 2m. If the jogger is running at a speed of 5ms-1 , how fast the image of the jogger appear to move when the jogger is 39m away?

A ball is in a hot air balloon that starts from rest at t = 0 and accelerates upwards at 2m/s2. After 10s, the ball is dropped from the balloon Draw the a-t graph of the ball from t = θ

What is the meaning of magnitude?

Define the focal plane of a Spherical Mirror.

Using differentials, find the approximate value of the following up to 3 places of decimal. (15)14

To keep valuable instruments away from the earth's magnetic field, they are enclosed in iron boxes. Explain.

define the counter current mechanism.

Partial charges are involved in:

Two cars are moving on two perpendicular roads towards a crossing with uniform speeds of 72 km/hr and 36 km/hr. If first car blows horn of frequency 280 Hz, then the frequency of horn heard by the driver of second car when line joining the cars make 45∘ angle with the roads; will be

The potential energy of particle of mass 'm' is given by U=12kx2 for x<0 and U = 0 for x ≥ 0. If total mechanical energy of the particle is E. Then its speed at x=√2Ek is