50278 + Interview Questions in Physics Page 97 InterviewSolution

4801.	The ground state energy of hydrogen atom is –13.6 eV. What are thekinetic and potential energies of the electron in this state?
Answer» The ground state energy of hydrogen atom is –13.6 eV. What are thekinetic and potential energies of the electron in this state?

Discussion

4802.	The halogen that is used as a germicide and disinfectant is:
Answer» The halogen that is used as a germicide and disinfectant is:

Discussion

4803.	A block of mass m is moving with a constant acceleration a on a rough horizontal plane. If the coefficient of friction between the block and ground is μ, the power delivered by the external agent after a time t from the beginning of motion is
Answer» A block of mass $m$ is moving with a constant acceleration $a$ on a rough horizontal plane. If the coefficient of friction between the block and ground is $μ$ , the power delivered by the external agent after a time $t$ from the beginning of motion is

Discussion

4804.	Aparallel plate capacitor ofcapacitance 20μ F charged by a voltage source whose potential is changing at the rate of V/s. The conduction current through the connecting wires, and the displacement current through the plates of the capacitor, would be, respectively:
Answer» Aparallel plate capacitor ofcapacitance 20μ F charged by a voltage source whose potential is changing at the rate of V/s. The conduction current through the connecting wires, and the displacement current through the plates of the capacitor, would be, respectively:

Discussion

4805.	Why do stainless steel vessels in our kitchen have a copper coating on the bottom?
Answer» Why do stainless steel vessels in our kitchen have a copper coating on the bottom?

Discussion

4806.	ntan electron is revolving in the 3rd orbit of hydrogen atom . what is its frequency ?n
Answer» ntan electron is revolving in the 3rd orbit of hydrogen atom . what is its frequency ?n

Discussion

4807.	Two beams, A and B, of plane polarized light with mutually perpendicular planes of polarization are seen through a polaroid. From the position when beam A has maximum intensity (and beam B has zero intensity), a rotation of polaroid through 30∘ makes the two beams appear equally bright. If the initial intensities of the two beams are IA and IB respectively, then IBIA will be equal to
Answer» Two beams, $A$ and $B$ , of plane polarized light with mutually perpendicular planes of polarization are seen through a polaroid. From the position when beam $A$ has maximum intensity (and beam $B$ has zero intensity), a rotation of polaroid through $30^{\circ}$ makes the two beams appear equally bright. If the initial intensities of the two beams are $I_{A}$ and $I_{B}$ respectively, then $\frac{I_{B}}{I_{A}}$ will be equal to

Discussion

4808.	A spherical cavity of radius R2 is removed from a solid sphere of radius R and the sphere is placed on a rough horizontal surface as shown in the figure. The sphere is given a gentle push and the friction is large enough to prevent slipping. Find the time period of oscillation of the sphere.
Answer» A spherical cavity of radius $\frac{R}{2}$ is removed from a solid sphere of radius $R$ and the sphere is placed on a rough horizontal surface as shown in the figure. The sphere is given a gentle push and the friction is large enough to prevent slipping. Find the time period of oscillation of the sphere.

Discussion

4809.	Morning breakfast gives 5000 cal to a 60 kg person. The efficiency of the person is 30 %. The height upto which the person can climb by using the energy obtained from breakfast is [Take g=10 m/s2]
Answer» Morning breakfast gives $5000 cal$ to a $60 kg$ person. The efficiency of the person is $30 %$ . The height upto which the person can climb by using the energy obtained from breakfast is [Take $g = 10 {m/s}^{2}$ ]

Discussion

4810.	A concrete sphere of radius R has a spherical cavity of radius r which is packed with sawdust. The specific gravities of concrete and sawdust are respectively 2.4 and 0.3. For this sphere to float with its entire volume submerged under water, ratio of mass of concrete to the mass of sawdust will be
Answer» A concrete sphere of radius $R$ has a spherical cavity of radius $r$ which is packed with sawdust. The specific gravities of concrete and sawdust are respectively $2.4$ and $0.3$ . For this sphere to float with its entire volume submerged under water, ratio of mass of concrete to the mass of sawdust will be

Discussion

4811.	Angular velocity of a body moving on a circular track is given by →ω=^i+^j+^k and the radius vector →r=2^i−2^j−2^k at the instant of time ‘t′. Then the magnitude of linear velocity of the body at that instant is.
Answer» Angular velocity of a body moving on a circular track is given by $\to ω =^i +^j +^k$ and the radius vector $\to r = 2^i - 2^j - 2^k$ at the instant of time $‘ t^{'}$ . Then the magnitude of linear velocity of the body at that instant is.

Discussion

4812.	A ball of mass 1 kg moves inside a smooth fixed spherical shell of radius 1 m with an initial velocity v=5 m/s from the bottom. What is the total force acting on the particle at point B?
Answer» A ball of mass $1 kg$ moves inside a smooth fixed spherical shell of radius $1 m$ with an initial velocity $v = 5 m/s$ from the bottom. What is the total force acting on the particle at point $B$ ?

Discussion

4813.	82.The ratio of height of image produced by concave lens to a height of object is 0.5.Assume focal length of the lens is 10 cm.find the distance of image from the lens
Answer» 82.The ratio of height of image produced by concave lens to a height of object is 0.5.Assume focal length of the lens is 10 cm.find the distance of image from the lens

Discussion

4814.	A fluid while flowing through a tube as shown passes through points A and B. Find the velocity of the fluid at point B.
Answer» A fluid while flowing through a tube as shown passes through points A and B. Find the velocity of the fluid at point B.

Discussion

4815.	In the shown figure a mass m slides down the frictionless surface from height h and collides with a uniform vertical rod of length L and mass M. After a collision, mass m sticks to the rod. The rod is free to rotate in a vertical plane about a fixed axis through O. Find the maximum angular deflection of the rod from its initial position
Answer» In the shown figure a mass m slides down the frictionless surface from height h and collides with a uniform vertical rod of length L and mass M. After a collision, mass m sticks to the rod. The rod is free to rotate in a vertical plane about a fixed axis through O. Find the maximum angular deflection of the rod from its initial position

4815.

In the shown figure a mass m slides down the frictionless surface from height h and collides with a uniform vertical rod of length L and mass M. After a collision, mass m sticks to the rod. The rod is free to rotate in a vertical plane about a fixed axis through O. Find the maximum angular deflection of the rod from its initial position

Answer»

In the shown figure a mass m slides down the frictionless surface from height h and collides with a uniform vertical rod of length L and mass M. After a collision, mass m sticks to the rod. The rod is free to rotate in a vertical plane about a fixed axis through O. Find the maximum angular deflection of the rod from its initial position

Discussion

4816.	25.Two soap bubbles of radii 2 cm and 4cm join to form a double bubble in air,then the radius of curvature of interface is 2cm 4cm 2\sqrt{}3cm 2\sqrt{}5cm
Answer» 25.Two soap bubbles of radii 2 cm and 4cm join to form a double bubble in air,then the radius of curvature of interface is 2cm 4cm 2\sqrt{}3cm 2\sqrt{}5cm

Discussion

4817.	Answerthe following:(a) The triple-point of water is a standardfixed point in modern thermometry. Why? What is wrong in taking themelting point of ice and the boiling point of water as standard fixedpoints (as was originally done in the Celsius scale)?(b) There were two fixed points in the originalCelsius scale as mentioned above which were assigned the number 0 °Cand 100 °C respectively. On the absolute scale, one of the fixedpoints is the triple-point of water, which on the Kelvin absolutescale is assigned the number 273.16 K. What is the other fixed pointon this (Kelvin) scale?(c) The absolute temperature (Kelvin scale) Tis related to the temperature tcon the Celsius scale by tc= T –273.15Whydo we have 273.15 in this relation, and not 273.16?(d) What is the temperature of the triple-pointof water on an absolute scale whose unit interval size is equal tothat of the Fahrenheit scale?
Answer» Answer the following: (a) The triple-point of water is a standard fixed point in modern thermometry. Why? What is wrong in taking the melting point of ice and the boiling point of water as standard fixed points (as was originally done in the Celsius scale)? (b) There were two fixed points in the original Celsius scale as mentioned above which were assigned the number 0 °C and 100 °C respectively. On the absolute scale, one of the fixed points is the triple-point of water, which on the Kelvin absolute scale is assigned the number 273.16 K. What is the other fixed point on this (Kelvin) scale? (c) The absolute temperature (Kelvin scale) T is related to the temperature t_c on the Celsius scale by t_c = T – 273.15 Why do we have 273.15 in this relation, and not 273.16? (d) What is the temperature of the triple-point of water on an absolute scale whose unit interval size is equal to that of the Fahrenheit scale?

4817.

Answerthe following:(a) The triple-point of water is a standardfixed point in modern thermometry. Why? What is wrong in taking themelting point of ice and the boiling point of water as standard fixedpoints (as was originally done in the Celsius scale)?(b) There were two fixed points in the originalCelsius scale as mentioned above which were assigned the number 0 °Cand 100 °C respectively. On the absolute scale, one of the fixedpoints is the triple-point of water, which on the Kelvin absolutescale is assigned the number 273.16 K. What is the other fixed pointon this (Kelvin) scale?(c) The absolute temperature (Kelvin scale) Tis related to the temperature tcon the Celsius scale by tc= T –273.15Whydo we have 273.15 in this relation, and not 273.16?(d) What is the temperature of the triple-pointof water on an absolute scale whose unit interval size is equal tothat of the Fahrenheit scale?

Answer»

Answer
the following:

(a) The triple-point of water is a standard
fixed point in modern thermometry. Why? What is wrong in taking the
melting point of ice and the boiling point of water as standard fixed
points (as was originally done in the Celsius scale)?

(b) There were two fixed points in the original
Celsius scale as mentioned above which were assigned the number 0 °C
and 100 °C respectively. On the absolute scale, one of the fixed
points is the triple-point of water, which on the Kelvin absolute
scale is assigned the number 273.16 K. What is the other fixed point
on this (Kelvin) scale?

(c) The absolute temperature (Kelvin scale) T
is related to the temperature t_c
on the Celsius scale by

t_c
= T –
273.15

Why
do we have 273.15 in this relation, and not 273.16?

(d) What is the temperature of the triple-point
of water on an absolute scale whose unit interval size is equal to
that of the Fahrenheit scale?

Discussion

4818.	In the circuit of figure, V0 is ___V.15
Answer» In the circuit of figure, $V_{0}$ is ___V. 15

Discussion

4819.	In an electrical circuit, two resistors of 2 Ω and 4 Ω respectively are connected in series to a 6 V battery. The heat dissipated by the 4 Ω resistor in 5 s will be:
Answer» In an electrical circuit, two resistors of $2 Ω$ and $4 Ω$ respectively are connected in series to a $6 V$ battery. The heat dissipated by the 4 $Ω$ resistor in $5 s$ will be:

Discussion

4820.	A magnetic needle is kept in a non-uniform magnetic field. It experiences:
Answer» A magnetic needle is kept in a non-uniform magnetic field. It experiences:

Discussion

4821.	A person can swim in still water at 5m/s. How much time will he take to move a distance of 120m in stream of water flowing at 1m/s up stream and downstream respectively.
Answer» A person can swim in still water at 5m/s. How much time will he take to move a distance of 120m in stream of water flowing at 1m/s up stream and downstream respectively.

Discussion

4822.	What is the density of water at a depth where pressure is 80.0 atm, given that its density at the surface is 1.03×103 kg/m3?
Answer» What is the density of water at a depth where pressure is 80.0 atm, given that its density at the surface is $1.03 \times 10^{3} k g / m^{3}$ ?

Discussion

4823.	Explain the statement ," electric lines of force have a tendency to contract in length like a stretched string "
Answer» Explain the statement ," electric lines of force have a tendency to contract in length like a stretched string "

Discussion

4824.	In YDSE the resul†an t intensity at a point on the screen is 50% of the maximum intensity of bright fringe then phase difference between the two interfering waves at that point is
Answer» In YDSE the resul†an t intensity at a point on the screen is 50% of the maximum intensity of bright fringe then phase difference between the two interfering waves at that point is

Discussion

4825.	There is an infinite straight chain of alternating charges q and -q. The distance between the two neighbouringcharges is equal to 'a'. The interaction energy of anycharge with all the other charges will be
Answer» There is an infinite straight chain of alternating charges q and -q. The distance between the two neighbouringcharges is equal to 'a'. The interaction energy of anycharge with all the other charges will be

Discussion

4826.	In the figure shown P1 and P2 are massless pulleys. P1 is fixed and P2 can move. Masses of A, B and C are 9m64, 2m and m respectively. All contacts are smooth and the string is massless. If θ=tan−1(34), then the acceleration of block C in m/s2 is
Answer» In the figure shown $P_{1}$ and $P_{2}$ are massless pulleys. $P_{1}$ is fixed and $P_{2}$ can move. Masses of A, B and C are $\frac{9 m}{64},$ $2 m$ and $m$ respectively. All contacts are smooth and the string is massless. If $θ = {tan}^{- 1} (\frac{3}{4})$ , then the acceleration of block $C$ in $m / s^{2}$ is

Discussion

4827.	relation between second ionisation and electronic configration
Answer» relation between second ionisation and electronic configration

Discussion

4828.	Paragraph for below questionनीचे दिये गये प्रश्न के लिए अनुच्छेदA particle of mass 1 kg, is moving along x axis under conservative forces only. The potential energy U(x) is given by U(x) = 10 + (x – 3)2, where x is in metre and U(x) is in joule. At x = 5 m, the particle has kinetic energy of 10 J. The total mechanical energy of the particle remains constant at every position. Answer the following question.1 kg द्रव्यमान का एक कण x अक्ष के अनुदिश केवल संरक्षी बलों के प्रभाव में गतिशील है। स्थितिज ऊर्जा U(x) को U(x) = 10 + (x – 3)2 द्वारा व्यक्त किया जाता है, जहाँ x मीटर में है तथा U(x) जूल में है। x = 5 m पर, कण की गतिज ऊर्जा 10 J है। कण की कुल यांत्रिक ऊर्जा प्रत्येक स्थिति पर नियत रहती है। निम्नलिखित प्रश्न का उत्तर दीजिए।Q. Maximum speed of the particle isप्रश्न - कण की अधिकतम चाल है
Answer» Paragraph for below question नीचे दिये गये प्रश्न के लिए अनुच्छेद A particle of mass 1 kg, is moving along x axis under conservative forces only. The potential energy U(x) is given by U(x) = 10 + (x – 3)², where x is in metre and U(x) is in joule. At x = 5 m, the particle has kinetic energy of 10 J. The total mechanical energy of the particle remains constant at every position. Answer the following question. 1 kg द्रव्यमान का एक कण x अक्ष के अनुदिश केवल संरक्षी बलों के प्रभाव में गतिशील है। स्थितिज ऊर्जा U(x) को U(x) = 10 + (x – 3)² द्वारा व्यक्त किया जाता है, जहाँ x मीटर में है तथा U(x) जूल में है। x = 5 m पर, कण की गतिज ऊर्जा 10 J है। कण की कुल यांत्रिक ऊर्जा प्रत्येक स्थिति पर नियत रहती है। निम्नलिखित प्रश्न का उत्तर दीजिए। Q. Maximum speed of the particle is प्रश्न - कण की अधिकतम चाल है

4828.

Paragraph for below questionनीचे दिये गये प्रश्न के लिए अनुच्छेदA particle of mass 1 kg, is moving along x axis under conservative forces only. The potential energy U(x) is given by U(x) = 10 + (x – 3)2, where x is in metre and U(x) is in joule. At x = 5 m, the particle has kinetic energy of 10 J. The total mechanical energy of the particle remains constant at every position. Answer the following question.1 kg द्रव्यमान का एक कण x अक्ष के अनुदिश केवल संरक्षी बलों के प्रभाव में गतिशील है। स्थितिज ऊर्जा U(x) को U(x) = 10 + (x – 3)2 द्वारा व्यक्त किया जाता है, जहाँ x मीटर में है तथा U(x) जूल में है। x = 5 m पर, कण की गतिज ऊर्जा 10 J है। कण की कुल यांत्रिक ऊर्जा प्रत्येक स्थिति पर नियत रहती है। निम्नलिखित प्रश्न का उत्तर दीजिए।Q. Maximum speed of the particle isप्रश्न - कण की अधिकतम चाल है

Answer»

Paragraph for below question

नीचे दिये गये प्रश्न के लिए अनुच्छेद

A particle of mass 1 kg, is moving along x axis under conservative forces only. The potential energy U(x) is given by U(x) = 10 + (x – 3)², where x is in metre and U(x) is in joule. At x = 5 m, the particle has kinetic energy of 10 J. The total mechanical energy of the particle remains constant at every position. Answer the following question.

1 kg द्रव्यमान का एक कण x अक्ष के अनुदिश केवल संरक्षी बलों के प्रभाव में गतिशील है। स्थितिज ऊर्जा U(x) को U(x) = 10 + (x – 3)² द्वारा व्यक्त किया जाता है, जहाँ x मीटर में है तथा U(x) जूल में है। x = 5 m पर, कण की गतिज ऊर्जा 10 J है। कण की कुल यांत्रिक ऊर्जा प्रत्येक स्थिति पर नियत रहती है। निम्नलिखित प्रश्न का उत्तर दीजिए।

Q. Maximum speed of the particle is

प्रश्न - कण की अधिकतम चाल है

Discussion

4829.	One arm of a current carrying loop is in the shape an arc of a circle of radius a while the other is a straight segment, as shown. If θ=60∘, the magnitude of dipole moment of the loop is
Answer» One arm of a current carrying loop is in the shape an arc of a circle of radius $a$ while the other is a straight segment, as shown. If $θ = 60^{\circ}$ , the magnitude of dipole moment of the loop is

Discussion

4830.	A beam of electron is used in a YDSE experiment. The slit width is d. When the velocity of electron is increased, then
Answer» A beam of electron is used in a YDSE experiment. The slit width is d. When the velocity of electron is increased, then

Discussion

4831.	A charged particle of specific charge α moves with a velocity v = v0i in a magnetic field →B=B0√2(^j+^k). Then the (specific charge = charge per unit mass)
Answer» A charged particle of specific charge α moves with a velocity v = $v_{0} i$ in a magnetic field $\to B = \frac{B_{0}}{\sqrt{2}} (^j +^k)$ . Then the (specific charge = charge per unit mass)

Discussion

4832.	A block of weight 5 N is pushed against a vertical wall by a force 12 N. The coefficient of friction between the wall and block is 0.6. The magnitude of the net contact force will be
Answer» A block of weight $5 N$ is pushed against a vertical wall by a force $12 N$ . The coefficient of friction between the wall and block is $0.6$ . The magnitude of the net contact force will be

Discussion

4833.	In the formation of primary rainbow, the sunlight rays emerge at from a raindrop after
Answer» In the formation of primary rainbow, the sunlight rays emerge at from a raindrop after

Discussion

4834.	Three constant forces F1 = 2i-3j+2k, F2 = i+j-k, and F3 = 3i+j-2k in newtons displace a particle from (1, -1, 2) to (-1, -1, 3) and then to (2, 2, 0) (displacement being measured in meteres). Find the total work done by the forces.
Answer» Three constant forces F1 = 2i-3j+2k, F2 = i+j-k, and F3 = 3i+j-2k in newtons displace a particle from (1, -1, 2) to (-1, -1, 3) and then to (2, 2, 0) (displacement being measured in meteres). Find the total work done by the forces.

Discussion

4835.	Estimate the average mass density of a sodium atom assuming its size to be about 2.5 Å. (Use the known values of Avogadro’s number and the atomic mass of sodium). Compare it with the mass density of sodium in its crystalline phase : 970 kg m–3. Are the two densities of the same order of magnitude ? If so, why ?
Answer» Estimate the average mass density of a sodium atom assuming its size to be about 2.5 Å. (Use the known values of Avogadro’s number and the atomic mass of sodium). Compare it with the mass density of sodium in its crystalline phase : 970 kg m–3. Are the two densities of the same order of magnitude ? If so, why ?

Discussion

4836.	What controls the amount of light entering the eye,pupil or iris?
Answer» What controls the amount of light entering the eye,pupil or iris?

Discussion

4837.	A body of mass m is moving in a circle of radius r with a constant speed v. The force on the body is mv2r and is directed towards the centre. What is the work done by this force in moving the body over half the circumference of the circle
Answer» A body of mass m is moving in a circle of radius r with a constant speed v. The force on the body is $\frac{m v^{2}}{r}$ and is directed towards the centre. What is the work done by this force in moving the body over half the circumference of the circle

Discussion

4838.	Prove that {\operatorname{tan3x-\operatorname{tan2x-\operatorname{tanx=\operatorname{tanx\operatorname{tan2x\operatorname{tan3x
Answer» Prove that {\operatorname{tan3x-\operatorname{tan2x-\operatorname{tanx=\operatorname{tanx\operatorname{tan2x\operatorname{tan3x

Discussion

4839.	13.A charged particle having charge q is moving with a speed v along x axis .It enters a region of space where an electric field E=Ej and a magnetic field B are both present . The particle on emerging from this region is observed to be moving along the x axis only . What is the direction of B
Answer» 13.A charged particle having charge q is moving with a speed v along x axis .It enters a region of space where an electric field E=Ej and a magnetic field B are both present . The particle on emerging from this region is observed to be moving along the x axis only . What is the direction of B

Discussion

4840.	the speed of sound in hydrogen at NTP, is 1270 m/s. then speed in a mixure of hydrogen and oxygen in the ratio 4:1 by volume (in m/s) will be (1) 635 (2) 318 (3) 158 (4) 1270
Answer» the speed of sound in hydrogen at NTP, is 1270 m/s. then speed in a mixure of hydrogen and oxygen in the ratio 4:1 by volume (in m/s) will be (1) 635 (2) 318 (3) 158 (4) 1270

Discussion

4841.	A hollow sphere of mass M=50 kg and radius r=(340π)13m is immersed in a tank of water (density ρw=103 kg/m3). The sphere is tied to the bottom of a tank by two wires A and B as shown. Tension in wire A is (g=10 m/s2)
Answer» A hollow sphere of mass $M = 50 kg$ and radius $r = {(\frac{3}{40 π})}^{\frac{1}{3}} m$ is immersed in a tank of water (density $ρ_{w} = 10^{3} {kg/m}^{3})$ . The sphere is tied to the bottom of a tank by two wires $A$ and $B$ as shown. Tension in wire $A$ is $(g = 10 {m/s}^{2})$

Discussion

4842.	In an electric field an electron is kept freely . if the electron is replaced by a proton what will be the relationship between the forces experienced by them
Answer» In an electric field an electron is kept freely . if the electron is replaced by a proton what will be the relationship between the forces experienced by them

Discussion

4843.	Area of orifice is a. Due to ejection of water of density p at a constant speed, the equilibrium compression in the spring is x. The speed of ejection of water is
Answer» Area of orifice is a. Due to ejection of water of density p at a constant speed, the equilibrium compression in the spring is x. The speed of ejection of water is

Discussion

4844.	A 15 g bullet is fired horizontally at a speed of 350 m/s into 1.2 kg block that hangs by a vertical string as shown below. The bullet remains embedded in the block. Find the speed of the bullet and the block.
Answer» A $15 g$ bullet is fired horizontally at a speed of $350 m/s$ into $1.2 kg$ block that hangs by a vertical string as shown below. The bullet remains embedded in the block. Find the speed of the bullet and the block.

Discussion

4845.	a shell is fired vertically upwards with a velocity v1 from a trolley moving horizontally with velocity v2. a person on the ground observes the motion of the shell as a parabola , whose horizontal range is?
Answer» a shell is fired vertically upwards with a velocity v1 from a trolley moving horizontally with velocity v2. a person on the ground observes the motion of the shell as a parabola , whose horizontal range is?

Discussion

4846.	An alpha particle is accelerated through a potential difference of 106 volt. Its kinetic energy will be
Answer» An alpha particle is accelerated through a potential difference of $10^{6} volt$ . Its kinetic energy will be

Discussion

4847.	Consider a two stage amplifier circuit shown in the figure below.The transconductance of the transistor T1 and T2 are gm1 and gm2 respectively, then the overall transconductance gm=IoVi is equal to (Assume α1=α2≈1)
Answer» Consider a two stage amplifier circuit shown in the figure below. $The transconductance of the transistor T_{1} and T_{2} are g_{m_{1}} and g_{m_{2}} respectively, then the overall transconductance g_{m} = \frac{I_{o}}{V_{i}} is equal to$ $(Assume α_{1} = α_{2} \approx 1)$

Discussion

4848.	When a diode is forward biased, it has a voltage drop of 0.5 V. The safe limit of current through the diode is 10 mA. If a battery of emf 1.5 V is used in a circuit. The value of minimum resistance to be connected in series with the diode so that the current does not exceed the safe limit is-
Answer» When a diode is forward biased, it has a voltage drop of $0.5 V .$ The safe limit of current through the diode is $10 mA$ . If a battery of emf $1.5 V$ is used in a circuit. The value of minimum resistance to be connected in series with the diode so that the current does not exceed the safe limit is-

Discussion

4849.	There is a uniform electric field E in the region between two parallel plates. A charged particle with a specific charge s enters the region with a speed u, in a direction parallel to the plates. The length of each plate is L. The time taken to come out of the plates is t and it suffers a vertical displacement. Also as y the particle crosses the plates, its direction of motion changes by an angle θ, then
Answer» There is a uniform electric field E in the region between two parallel plates. A charged particle with a specific charge s enters the region with a speed u, in a direction parallel to the plates. The length of each plate is L. The time taken to come out of the plates is t and it suffers a vertical displacement. Also as y the particle crosses the plates, its direction of motion changes by an angle $θ$ , then

Discussion

4850.	1. A boy standing near the edge of a cliff 125m above a river throws astone downward with a speed of 10m/s.find A) with what speed will the stone hit water
Answer» 1. A boy standing near the edge of a cliff 125m above a river throws astone downward with a speed of 10m/s.find A) with what speed will the stone hit water

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1. A boy standing near the edge of a cliff 125m above a river throws astone downward with a speed of 10m/s.find A) with what speed will the stone hit water