50278 + Interview Questions in Physics Page 271 InterviewSolution

13501.	Two similar springs P and Q have spring constants kP and kQ, such that kP>kQ. They are stretched, first by the same amount (case a ), then by the same force (case b ). The work done by the springs WP and WQ are related as, in case (a) and case (b), respectively
Answer» Two similar springs $P$ and $Q$ have spring constants $k_{P}$ and $k_{Q}$ , such that $k_{P} > k_{Q}$ . They are stretched, first by the same amount (case a ), then by the same force (case b ). The work done by the springs $W_{P}$ and $W_{Q}$ are related as, in case (a) and case (b), respectively

Discussion

13502.	The magnetic field in a region is given by B=3r, where r is the distance from the origin. The direction of the magnetic field is along the negative z-axis. A conducting rod of length 20 cm lies as shown in the figure. If the rod is rotating with an angular velocity of 4 rad/s, find the emf induced between the ends of the rod.
Answer» The magnetic field in a region is given by $B = 3 r$ , where $r$ is the distance from the origin. The direction of the magnetic field is along the negative $z-axis$ . A conducting rod of length $20 cm$ lies as shown in the figure. If the rod is rotating with an angular velocity of $4 rad/s$ , find the emf induced between the ends of the rod.

Discussion

13503.	A conducting rod AC of length 4l is rotated about a point O in a uniform magnetic field B as shown in the figure. If AO=l and OC=3l then
Answer» A conducting rod $AC$ of length $4 l$ is rotated about a point $O$ in a uniform magnetic field $B$ as shown in the figure. If $A O = l$ and $O C = 3 l$ then

Discussion

13504.	A 15 kg mass fastened to the end office Steel wire of unstretched length one metre is whirled in a vertical circle with angular velocity of 4 radian per second at the bottom of the circle the cross section area of the wire is 0.065 z square elongation of the wire when the mass is at the lowest point is
Answer» A 15 kg mass fastened to the end office Steel wire of unstretched length one metre is whirled in a vertical circle with angular velocity of 4 radian per second at the bottom of the circle the cross section area of the wire is 0.065 z square elongation of the wire when the mass is at the lowest point is

Discussion

13505.	an Alpha particle completes 40,000 revolutions in a cyclotron before exiting from . if potential difference between the dees is 5000 volt then energy gained by particle is1. 8MeV2. 800MeV
Answer» an Alpha particle completes 40,000 revolutions in a cyclotron before exiting from . if potential difference between the dees is 5000 volt then energy gained by particle is 1. 8MeV 2. 800MeV

Discussion

13506.	The contribution in the total current flowing through a semiconductor due to electrons and holes are <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}-->34 and <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}-->14 respectively. If the drift velocity of electrons is <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}-->52 times that of holes at this temperature, then the ratio of concentration of electrons and holes is
Answer» The contribution in the total current flowing through a semiconductor due to electrons and holes are <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> $\frac{3}{4}$ and <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> $\frac{1}{4}$ respectively. If the drift velocity of electrons is <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> $\frac{5}{2}$ times that of holes at this temperature, then the ratio of concentration of electrons and holes is

Discussion

13507.	The specific heat of a substance varies with temperature according to the function S=0.20+0.14T+0.023T2 with T in ∘C and S in cal/g∘C. What is the energy required to raise the temperature of 2.0 g of this substance from 5∘C to 15∘C?
Answer» The specific heat of a substance varies with temperature according to the function $S = 0.20 + 0.14 T + 0.023 T^{2}$ with $T$ in $^{\circ} C$ and $S$ in ${cal/g}^{\circ} C .$ What is the energy required to raise the temperature of $2.0 g$ of this substance from $5^{\circ} C$ to $15^{\circ} C$ ?

Discussion

13508.	A ball of mass 2 kg, travelling with a velocity 2^i+3^j+4^k m/s receives an impulse of 4^i+2^j N-s. What is the velocity of the ball immediately after the impulse is imparted?
Answer» A ball of mass $2 kg$ , travelling with a velocity $2^i + 3^j + 4^k m/s$ receives an impulse of $4^i + 2^j N-s$ . What is the velocity of the ball immediately after the impulse is imparted?

Discussion

13509.	Integrate the following functions. ∫sec2(7−4x)dx.
Answer» Integrate the following functions. $\int s e c^{2} (7 - 4 x) d x .$

Discussion

13510.	A charge q is placed at the corner of a regular cube of side l. Find electric flux passing through each of the adjacent face
Answer» A charge q is placed at the corner of a regular cube of side l. Find electric flux passing through each of the adjacent face

Discussion

13511.	A liquid soap bowl rests on a table in the dining car of SHATABDI Express. If the train is accelerating uniformly at rate of g4 in the forward direction, the angle made by the surface of the soap contained in the bowl with the horizontal is θ. Then,
Answer» A liquid soap bowl rests on a table in the dining car of SHATABDI Express. If the train is accelerating uniformly at rate of $\frac{g}{4}$ in the forward direction, the angle made by the surface of the soap contained in the bowl with the horizontal is $θ$ . Then,

Discussion

13512.	The frequency of tuning forks A and B are respectively 3% more and 2% less than the frequency of tuning fork C. When A and B are simultaneously excited, 5 beats per second are produced. Then the frequency of the tuning fork A (in Hz) is
Answer» The frequency of tuning forks $A$ and $B$ are respectively $3 %$ more and $2 %$ less than the frequency of tuning fork $C$ . When $A$ and $B$ are simultaneously excited, $5$ beats per second are produced. Then the frequency of the tuning fork $A$ (in $H z$ ) is

Discussion

13513.	A ball is thrown from the ground to clear a wall 3 m high at a distance of 6 m and falls 18 m away from the wall, the angle of projection of ball is
Answer» A ball is thrown from the ground to clear a wall $3 m$ high at a distance of $6 m$ and falls $18 m$ away from the wall, the angle of projection of ball is

Discussion

13514.	A fixed thermally conducting cylinder has a radius R and height L0. The cylinder is open at its bottom and has a small hole at its top. A piston of mass M is held at a distance L from the top surface, as shown. The atmospheric pressure is P0. The piston is now pulled out slowly and held at a distance 2L from the top. The pressure in the cylinder between its top and the piston will be
Answer» A fixed thermally conducting cylinder has a radius R and height $L_{0}$ . The cylinder is open at its bottom and has a small hole at its top. A piston of mass M is held at a distance L from the top surface, as shown. The atmospheric pressure is $P_{0}$ . The piston is now pulled out slowly and held at a distance 2L from the top. The pressure in the cylinder between its top and the piston will be

13514.

A fixed thermally conducting cylinder has a radius R and height L0. The cylinder is open at its bottom and has a small hole at its top. A piston of mass M is held at a distance L from the top surface, as shown. The atmospheric pressure is P0. The piston is now pulled out slowly and held at a distance 2L from the top. The pressure in the cylinder between its top and the piston will be

Answer»

A fixed thermally conducting cylinder has a radius R and height $L_{0}$ . The cylinder is open at its bottom and has a small hole at its top. A piston of mass M is held at a distance L from the top surface, as shown. The atmospheric pressure is $P_{0}$ .

The piston is now pulled out slowly and held at a distance 2L from the top. The pressure in the cylinder between its top and the piston will be

Discussion

13515.	Two parallel plates are 0.03m apart. The electric field intensity between them is 3000 newton per coulomb. Calculate the potential difference between the plates?
Answer» Two parallel plates are 0.03m apart. The electric field intensity between them is 3000 newton per coulomb. Calculate the potential difference between the plates?

Discussion

13516.	A spring block arrangement is shown in the figure.The spring is stretched along the inclined plane from position A (unstretched) to position B. Find the change in potential energy of the spring.
Answer» A spring block arrangement is shown in the figure. The spring is stretched along the inclined plane from position $A$ (unstretched) to position $B$ . Find the change in potential energy of the spring.

Discussion

13517.	A beam of protons with speed 4×105ms-1 enters a uniform magnetic field of 0.3Tat an angle of 60° to the magnetic field. The pitch of the resulting helical path of protons is close to: (Mass of the proton = 1.67×10-27kgcharge of the proton =1.69×10-19C). 4cm 2cm12cm 5cm
Answer» A beam of protons with speed $4 \times 10^{5} {ms}^{- 1}$ enters a uniform magnetic field of $0.3 T$ at an angle of $60^{°}$ to the magnetic field. The pitch of the resulting helical path of protons is close to: (Mass of the proton = $1.67 \times 10^{- 27} kg$ charge of the proton = $1.69 \times 10^{- 19} C$ ). $4 cm$ $2 cm$ $12 cm$ $5 cm$

13517.

A beam of protons with speed 4×105ms-1 enters a uniform magnetic field of 0.3Tat an angle of 60° to the magnetic field. The pitch of the resulting helical path of protons is close to: (Mass of the proton = 1.67×10-27kgcharge of the proton =1.69×10-19C). 4cm 2cm12cm 5cm

Answer»

A beam of protons with speed $4 \times 10^{5} {ms}^{- 1}$ enters a uniform magnetic field of $0.3 T$ at an angle of $60^{°}$ to the magnetic field. The pitch of the resulting helical path of protons is close to: (Mass of the proton = $1.67 \times 10^{- 27} kg$ charge of the proton = $1.69 \times 10^{- 19} C$ ).

$4 cm$
$2 cm$
$12 cm$
$5 cm$

Discussion

13518.	statement :electric potential energy is of a dipole in external electric field is work done in moving dipole from infinity to that point without changing ACCLERATION why without changing accleration
Answer» statement :electric potential energy is of a dipole in external electric field is work done in moving dipole from infinity to that point without changing ACCLERATION why without changing accleration

Discussion

13519.

Given a single area with two generating units. Unit Rating Speed drop R (per unit on unit base) 1 400 0.04 2 800 0.05 The units share a load of P1=200MW,P2=500MW. The units are operating in parallel to share a load of 700 MW at 50 Hz frequency. The load is increased by 130 MW with B = 0, The value of new frequency caused by steady state frequency deviation is _______ Hz.49.75

Answer» Given a single area with two generating units.

Unit	Rating	Speed drop R (per unit on unit base)
1	400	0.04
2	800	0.05

The units share a load of

P_{1} = 200 M W, P_{2} = 500 M W

. The units are operating in parallel to share a load of 700 MW at 50 Hz frequency. The load is increased by 130 MW with B = 0, The value of new frequency caused by steady state frequency deviation is _______ Hz.

49.75

Discussion

13520.	A person driving a car with a speed 72km/h, suddenly sees a boy crossing the road . If the distance moved by car, before the person applies brakes is 5m, the reaction time if the person i
Answer» A person driving a car with a speed 72km/h, suddenly sees a boy crossing the road . If the distance moved by car, before the person applies brakes is 5m, the reaction time if the person i

Discussion

13521.	A table with smooth horizontal surface is placed in a cabin which moves in a circle of a large radius R with ω. A smooth pulley of small radius is fastened to the table. Two masses m and 2m placed on the table are connected through a string going over the pulley. Initially the masses are held by a person with the strings along the outward radius and then the system is released from rest (with respect to the cabin). Find the magnitude of the initial acceleration of the masses as seen from the cabin.
Answer» A table with smooth horizontal surface is placed in a cabin which moves in a circle of a large radius R with $ω$ . A smooth pulley of small radius is fastened to the table. Two masses m and 2m placed on the table are connected through a string going over the pulley. Initially the masses are held by a person with the strings along the outward radius and then the system is released from rest (with respect to the cabin). Find the magnitude of the initial acceleration of the masses as seen from the cabin.

13521.

A table with smooth horizontal surface is placed in a cabin which moves in a circle of a large radius R with ω. A smooth pulley of small radius is fastened to the table. Two masses m and 2m placed on the table are connected through a string going over the pulley. Initially the masses are held by a person with the strings along the outward radius and then the system is released from rest (with respect to the cabin). Find the magnitude of the initial acceleration of the masses as seen from the cabin.

Answer»

A table with smooth horizontal surface is placed in a cabin which moves in a circle of a large radius R with $ω$ . A smooth pulley of small radius is fastened to the table. Two masses m and 2m placed on the table are connected through a string going over the pulley. Initially the masses are held by a person with the strings along the outward radius and then the system is released from rest (with respect to the cabin). Find the magnitude of the initial acceleration of the masses as seen from the cabin.

Discussion

13522.	The damping ratio of a single degree of freedom spring mass damper system with mass of 1 kg. stiffness 100 N/m and viscous damping coefficient of 5 Ns/m is
Answer» The damping ratio of a single degree of freedom spring mass damper system with mass of 1 kg. stiffness 100 N/m and viscous damping coefficient of 5 Ns/m is

Discussion

13523.	The principal section of glass prism is an isosceles ΔPQR with PQ = PR. The face PR is silvered. A ray is incident perpendicularly on face PQ, and after two reflections, it emerges from base QR, normal to it. Find the angle (in degree) of the prism.
Answer» The principal section of glass prism is an isosceles ΔPQR with PQ = PR. The face PR is silvered. A ray is incident perpendicularly on face PQ, and after two reflections, it emerges from base QR, normal to it. Find the angle (in degree) of the prism.

Discussion

13524.	A ball is thrown vertically upwards. Which of the following plots represents the speed-time graph of the ball during its flight if the air resistance is not ignored? (Assume that magnitude of resistive force is constant )
Answer» A ball is thrown vertically upwards. Which of the following plots represents the speed-time graph of the ball during its flight if the air resistance is not ignored? (Assume that magnitude of resistive force is constant )

Discussion

13525.	Find the charge through capacitor C5 in the given circuit?
Answer» Find the charge through capacitor $C_{5}$ in the given circuit?

Discussion

13526.	The energy density in a parallel plate capacitor is given by 3.8×10−9Jm3. Find the magnitude of electric field in the region between the plate.
Answer» The energy density in a parallel plate capacitor is given by $3.8 \times 10^{- 9} \frac{J}{m^{3}}$ . Find the magnitude of electric field in the region between the plate.

Discussion

13527.	what is specific charge and what is its impor†an ce
Answer» what is specific charge and what is its impor†an ce

Discussion

13528.	Solve tan2x=−cot(x+π3)
Answer» Solve $tan 2 x = - cot (x + \frac{π}{3})$

Discussion

13529.	Light of wavelength 6000 ∘A is incident along the normal on a glass plate of refractive index 1.5. What should be the smallest thickness of the plate which will make it appear darker when reflection is observed ?
Answer» Light of wavelength $6000 \circ A$ is incident along the normal on a glass plate of refractive index 1.5. What should be the smallest thickness of the plate which will make it appear darker when reflection is observed ?

Discussion

13530.	What is the y coordinate of the centre of mass of a semi-circular disc as shown in the figure? The smaller disc has been cut from the larger one. Consider the discs to have uniform density. Consider the axes and origin as shown in figure.
Answer» What is the $y$ coordinate of the centre of mass of a semi-circular disc as shown in the figure? The smaller disc has been cut from the larger one. Consider the discs to have uniform density. Consider the axes and origin as shown in figure.

Discussion

13531.	52.Two concentric spheres of radii R and 2R are carrying charges Q and -2Q respectively. If the charge on inner sphere is doubled,the potential difference between the two spheres will 1)become two times 2)become four times 3)be halved 4)reaming same
Answer» 52.Two concentric spheres of radii R and 2R are carrying charges Q and -2Q respectively. If the charge on inner sphere is doubled,the potential difference between the two spheres will 1)become two times 2)become four times 3)be halved 4)reaming same

Discussion

13532.	4.To what height a cylindrical vessel be filled with a homogeneous liquid to make to force on bottom equal to force of side? [R=radius of the vessel] A. 2R B. R C. R/2 D. 4R Click here to view details:
Answer» 4.To what height a cylindrical vessel be filled with a homogeneous liquid to make to force on bottom equal to force of side? [R=radius of the vessel] A. 2R B. R C. R/2 D. 4R Click here to view details:

Discussion

13533.	for a monochromatic radiation incident on a photosensitive surface why do all photoelectrons not come out with the same energy??
Answer» for a monochromatic radiation incident on a photosensitive surface why do all photoelectrons not come out with the same energy??

Discussion

13534.	A screw gauge has the least count of 0.01 mm and there are 50 divisions in its circular scale. The pitch of the screw gauge is :
Answer» A screw gauge has the least count of $0.01 mm$ and there are $50$ divisions in its circular scale. The pitch of the screw gauge is :

Discussion

13535.	nta stone of mass 2kg is attached with a string of length 2m rotated in a vertical circlen nttension in the string at highest poinnt is 44N.Calculate tension:-n nt1)at lowest pointn nt2)when string is 60degree with vertical in lower half circlen nt3)when string is 60degree with vertical in upper half circlen nt4)when string become horizontaln
Answer» nta stone of mass 2kg is attached with a string of length 2m rotated in a vertical circlen nttension in the string at highest poinnt is 44N.Calculate tension:-n nt1)at lowest pointn nt2)when string is 60degree with vertical in lower half circlen nt3)when string is 60degree with vertical in upper half circlen nt4)when string become horizontaln

Discussion

13536.	A point object is placed mid-way between two plane mirrors which are a distance apart. The plane mirrors forms an infinite number of images due to multiple reflections. The distance between the nth order image (i.e nth image in both the mirrors) formed in the two mirrors is
Answer» A point object is placed mid-way between two plane mirrors which are $a$ distance apart. The plane mirrors forms an infinite number of images due to multiple reflections. The distance between the $n^{th}$ order image (i.e $n^{t h}$ image in both the mirrors) formed in the two mirrors is

Discussion

13537.	A Carnot engine whose sink is at 300 K has anefficiency of 40%. By how much should thetemperature of source be increased to as toincrease its efficiency by 50% of original efficiency?(1) 150 K(3) 300 K(2) 250 K(4) 450 K
Answer» A Carnot engine whose sink is at 300 K has anefficiency of 40%. By how much should thetemperature of source be increased to as toincrease its efficiency by 50% of original efficiency?(1) 150 K(3) 300 K(2) 250 K(4) 450 K

Discussion

13538.	32. a ball is bouncing elastically with a speed of 1 m/s between walls of a railway compartment of size 10m in a direction perpendicular to the walls . the train is moving at a constant velocity of 10 m/s parallel to the direction of motion of the ball. as seen from the ground, 1. the direction of motion of the ball changes every 10 seconds 2. the speed of the ball changes every 10 seconds. 3.average speed of the ball over any 20 second interval is fixed. 4.the acceleration fo the ball is the same as from the train
Answer» 32. a ball is bouncing elastically with a speed of 1 m/s between walls of a railway compartment of size 10m in a direction perpendicular to the walls . the train is moving at a constant velocity of 10 m/s parallel to the direction of motion of the ball. as seen from the ground, 1. the direction of motion of the ball changes every 10 seconds 2. the speed of the ball changes every 10 seconds. 3.average speed of the ball over any 20 second interval is fixed. 4.the acceleration fo the ball is the same as from the train

Discussion

13539.	The magnitude of potential energy per unit mass of an object at the surface of earth is E, the escape velocity of the object is
Answer» The magnitude of potential energy per unit mass of an object at the surface of earth is $E$ , the escape velocity of the object is

Discussion

13540.	A uniformly charged ring has linear charge density 4Cm. What is the electric potential at its centre?
Answer» A uniformly charged ring has linear charge density $4 \frac{C}{m}$ . What is the electric potential at its centre?

Discussion

13541.	A body is thrown vertically upwards at a velocity of 4.9m/s . another body is thrown vertically downwards at the same initial speed simultaneously from the max height that can be achieved by first body.determine when and where the bodies meet
Answer» A body is thrown vertically upwards at a velocity of 4.9m/s . another body is thrown vertically downwards at the same initial speed simultaneously from the max height that can be achieved by first body.determine when and where the bodies meet

Discussion

13542.	76. In the displacement method using a convex lens we obtained two images corresponding to a seperation d of the lens . One image is magnified as much as the other is diminished . If m is the magnification of one image ,find focal length of lens
Answer» 76. In the displacement method using a convex lens we obtained two images corresponding to a seperation d of the lens . One image is magnified as much as the other is diminished . If m is the magnification of one image ,find focal length of lens

Discussion

13543.	"two positively charged identical plates placed parallel to each other form parallel plate capacitor" it is possible or not ?
Answer» "two positively charged identical plates placed parallel to each other form parallel plate capacitor" it is possible or not ?

Discussion

13544.	What is the value of a force which has two rec†an gular components of 15 N and 8 N
Answer» What is the value of a force which has two rec†an gular components of 15 N and 8 N

Discussion

13545.	24. A block of mass m is projrctedhorizontally on a conveyer belt of lenght L on two small rollers moving at speed v . Find the speed with which the block is projected so that the heat dissipated against friction will be maximum.
Answer» 24. A block of mass m is projrctedhorizontally on a conveyer belt of lenght L on two small rollers moving at speed v . Find the speed with which the block is projected so that the heat dissipated against friction will be maximum.

Discussion

13546.	What should be the orientation of an electric dipole in a uniform electric field, that corresponds to stable equilibrium ?
Answer» What should be the orientation of an electric dipole in a uniform electric field, that corresponds to stable equilibrium ?

Discussion

13547.	Two sound waves travelling in opposite direction interfere to produce a standing wave in resonance column tube. The equation of standing wave is y = 2 sin (2x) cos(100t),where x is in metre and t is in seconds. What is the distance of first pressure node from closed end of tube6.9 cm7.85cm✓
Answer» Two sound waves travelling in opposite direction interfere to produce a standing wave in resonance column tube. The equation of standing wave is y = 2 sin (2x) cos(100t),where x is in metre and t is in seconds. What is the distance of first pressure node from closed end of tube 6.9 cm 7.85cm✓

Discussion

13548.	23.Find the net force on a point charge +q not and that value for y is much less than a ?
Answer» 23.Find the net force on a point charge +q not and that value for y is much less than a ?

Discussion

13549.	why is it that when theta is 90 degree the particle moves in a circle and what if theta is 15 degree?
Answer» why is it that when theta is 90 degree the particle moves in a circle and what if theta is 15 degree?

Discussion

13550.	The energy (E) of a photon of light is related to its frequency (f) as E = hf. Here, h is Planck's constant. The value of Planck's constant is h = 6.62×10−34 J-s in Sl units. Convert it into CGS system of units
Answer» The energy (E) of a photon of light is related to its frequency (f) as E = hf. Here, h is Planck's constant. The value of Planck's constant is h = $6.62 \times 10^{- 34}$ J-s in Sl units. Convert it into CGS system of units

Discussion

Explore topic-wise InterviewSolutions in .

Two similar springs P and Q have spring constants kP and kQ, such that kP&gt;kQ. They are stretched, first by the same amount (case a ), then by the same force (case b ). The work done by the springs WP and WQ are related as, in case (a) and case (b), respectively

A conducting rod AC of length 4l is rotated about a point O in a uniform magnetic field B as shown in the figure. If AO=l and OC=3l then

an Alpha particle completes 40,000 revolutions in a cyclotron before exiting from . if potential difference between the dees is 5000 volt then energy gained by particle is1. 8MeV2. 800MeV

The specific heat of a substance varies with temperature according to the function S=0.20+0.14T+0.023T2 with T in ∘C and S in cal/g∘C. What is the energy required to raise the temperature of 2.0 g of this substance from 5∘C to 15∘C?

A ball of mass 2 kg, travelling with a velocity 2^i+3^j+4^k m/s receives an impulse of 4^i+2^j N-s. What is the velocity of the ball immediately after the impulse is imparted?

Integrate the following functions. ∫sec2(7−4x)dx.

A charge q is placed at the corner of a regular cube of side l. Find electric flux passing through each of the adjacent face

A liquid soap bowl rests on a table in the dining car of SHATABDI Express. If the train is accelerating uniformly at rate of g4 in the forward direction, the angle made by the surface of the soap contained in the bowl with the horizontal is θ. Then,

The frequency of tuning forks A and B are respectively 3% more and 2% less than the frequency of tuning fork C. When A and B are simultaneously excited, 5 beats per second are produced. Then the frequency of the tuning fork A (in Hz) is

A ball is thrown from the ground to clear a wall 3 m high at a distance of 6 m and falls 18 m away from the wall, the angle of projection of ball is

Two parallel plates are 0.03m apart. The electric field intensity between them is 3000 newton per coulomb. Calculate the potential difference between the plates?

A spring block arrangement is shown in the figure.The spring is stretched along the inclined plane from position A (unstretched) to position B. Find the change in potential energy of the spring.

A beam of protons with speed 4×105ms-1 enters a uniform magnetic field of 0.3Tat an angle of 60° to the magnetic field. The pitch of the resulting helical path of protons is close to: (Mass of the proton = 1.67×10-27kgcharge of the proton =1.69×10-19C). 4cm 2cm12cm 5cm

statement :electric potential energy is of a dipole in external electric field is work done in moving dipole from infinity to that point without changing ACCLERATION why without changing accleration

A person driving a car with a speed 72km/h, suddenly sees a boy crossing the road . If the distance moved by car, before the person applies brakes is 5m, the reaction time if the person i

The damping ratio of a single degree of freedom spring mass damper system with mass of 1 kg. stiffness 100 N/m and viscous damping coefficient of 5 Ns/m is

The principal section of glass prism is an isosceles ΔPQR with PQ = PR. The face PR is silvered. A ray is incident perpendicularly on face PQ, and after two reflections, it emerges from base QR, normal to it. Find the angle (in degree) of the prism.

A ball is thrown vertically upwards. Which of the following plots represents the speed-time graph of the ball during its flight if the air resistance is not ignored? (Assume that magnitude of resistive force is constant )

Find the charge through capacitor C5 in the given circuit?

The energy density in a parallel plate capacitor is given by 3.8×10−9Jm3. Find the magnitude of electric field in the region between the plate.

what is specific charge and what is its impor†an ce

Solve tan2x=−cot(x+π3)

Light of wavelength 6000 ∘A is incident along the normal on a glass plate of refractive index 1.5. What should be the smallest thickness of the plate which will make it appear darker when reflection is observed ?

What is the y coordinate of the centre of mass of a semi-circular disc as shown in the figure? The smaller disc has been cut from the larger one. Consider the discs to have uniform density. Consider the axes and origin as shown in figure.

52.Two concentric spheres of radii R and 2R are carrying charges Q and -2Q respectively. If the charge on inner sphere is doubled,the potential difference between the two spheres will 1)become two times 2)become four times 3)be halved 4)reaming same

4.To what height a cylindrical vessel be filled with a homogeneous liquid to make to force on bottom equal to force of side? [R=radius of the vessel] A. 2R B. R C. R/2 D. 4R Click here to view details:

for a monochromatic radiation incident on a photosensitive surface why do all photoelectrons not come out with the same energy??

A screw gauge has the least count of 0.01 mm and there are 50 divisions in its circular scale. The pitch of the screw gauge is :

A point object is placed mid-way between two plane mirrors which are a distance apart. The plane mirrors forms an infinite number of images due to multiple reflections. The distance between the nth order image (i.e nth image in both the mirrors) formed in the two mirrors is

A Carnot engine whose sink is at 300 K has anefficiency of 40%. By how much should thetemperature of source be increased to as toincrease its efficiency by 50% of original efficiency?(1) 150 K(3) 300 K(2) 250 K(4) 450 K

The magnitude of potential energy per unit mass of an object at the surface of earth is E, the escape velocity of the object is

A uniformly charged ring has linear charge density 4Cm. What is the electric potential at its centre?

A body is thrown vertically upwards at a velocity of 4.9m/s . another body is thrown vertically downwards at the same initial speed simultaneously from the max height that can be achieved by first body.determine when and where the bodies meet

76. In the displacement method using a convex lens we obtained two images corresponding to a seperation d of the lens . One image is magnified as much as the other is diminished . If m is the magnification of one image ,find focal length of lens

"two positively charged identical plates placed parallel to each other form parallel plate capacitor" it is possible or not ?

What is the value of a force which has two rec†an gular components of 15 N and 8 N

24. A block of mass m is projrctedhorizontally on a conveyer belt of lenght L on two small rollers moving at speed v . Find the speed with which the block is projected so that the heat dissipated against friction will be maximum.

What should be the orientation of an electric dipole in a uniform electric field, that corresponds to stable equilibrium ?

Two sound waves travelling in opposite direction interfere to produce a standing wave in resonance column tube. The equation of standing wave is y = 2 sin (2x) cos(100t),where x is in metre and t is in seconds. What is the distance of first pressure node from closed end of tube6.9 cm7.85cm✓

23.Find the net force on a point charge +q not and that value for y is much less than a ?

why is it that when theta is 90 degree the particle moves in a circle and what if theta is 15 degree?

The energy (E) of a photon of light is related to its frequency (f) as E = hf. Here, h is Planck's constant. The value of Planck's constant is h = 6.62×10−34 J-s in Sl units. Convert it into CGS system of units

Two similar springs P and Q have spring constants kP and kQ, such that kP>kQ. They are stretched, first by the same amount (case a ), then by the same force (case b ). The work done by the springs WP and WQ are related as, in case (a) and case (b), respectively