This section includes 7 InterviewSolutions, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.
| 2. |
prove that the energy state of a particle in a potential well of finite width and infinite depth are discrete but they are not equispaced |
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Answer» The FINITE potential well is a CONCEPT from QUANTUM mechanics. It is an EXTENSION ... |
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| 3. |
6. A particle starts moving at t = 0 from origin alongthe (+ve) direction of x-axis. Its speed depends ondxthe distance travelled x as v = KX. If v=dtdvthen find x, v and a in terms of timedtand a =K2t2 kt K24 2 2(2)K22 kt K24 2 2(3)Kt? Kt2 K4 2 2(4)Kt2 kt K4 '2'2 |
| Answer» V = k√xdx/dt = k√xdx/√x = kdtintegerating both side2√x = KTX = k2t2/4v = dx/dt = k2t/2a = dv/dt = k2/2Hope it CLEARS...... | |
| 4. |
What is Joule Law?? if u know then only answer it!!!! |
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Answer» Hello Mate,Joule Law states that the rate of production of heat by a constant direct current is DIRECTLY proportional to the RESISTANCE of the circuit and to the square of the current. the PRINCIPLE that the INTERNAL energy of a given MASS of an ideal gas is solely a function of its temperature....Hope this helps you ☺️✌️❤️ |
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| 5. |
Derive and discuss dispersion relation of one dimensional monoatomic lattice vibrations |
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Answer» helloExplanation:One-dimensional lattice For simplicity we consider, first, a one-dimensional crystal lattice and ASSUME that the forces between the atoms in this lattice are PROPORTIONAL to relative displacements from the EQUILIBRIUM positions. where M is the mass of the ATOM..hope this helps u ☺️❤️❤️❤️ |
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| 6. |
(b) A train staring from rest attains a velocity of 72 km/h in 5 minutes. Assuming that the acceleration is uniform, find out the (i) acceleration(ii) the distance travelled by the train for attending this velocity? |
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Answer» tion:0.24 VELOCITY TRAVELLED by the trainacceleration does not CHANGE |
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| 7. |
20 .Resistor 1 has twice resistance of resistor 2. The two are connected inseries and a potentialKerence is maintained across the combination. The rateof thermal energy generation in 1 is:A. the same as that in 2B. twice that in 2D. four times that in 2E. one-fourth that in 2 |
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Answer» d) ........................... |
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| 8. |
A body of mass 1 kg hanging with a spring of spring constant 80 Nm is rotating in ahorizontal circle. The values of angularfrequency will be(a) 80.94 Hz(b) 89.4 Hz(c) 98.4 Hz(d) 108.6 Hz |
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| 9. |
The potential at point in an electric field is x volt what do you mean by that |
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Answer» The electric potential V is given as a FUNCTION of DISTANCE x by V=5x2+10x−9. The value of electric field at x=1 is. (All quantities are in SI units.) |
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| 10. |
09/20 15/ minThe length of the second hand of a watch is 1 cm. The velocity vector of the tip of the second hand in cm per second is? |
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Answer» 14m/s...................... |
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| 11. |
. The resultant oftwo vector A and B subtends an angle of 45° with either of them. The magnitudeof the resultant is(1) zero(3) A(2) V2A(4) 2A |
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Answer» The RESULTANT of two vectors A and B SUBTENDS an angle of 45° with either of them. The magnitude of. the resultant is. (a) ZERO. |
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| 12. |
18. The resistance of resistor 1 is twice the resistance of resistor 2. The two are connected in parallel and a potential difference is maintained across thecombination. Then:A. the current in 1 is twice that in 2B. the current in 1 is half that in 2C. the potential difference across 1 is twice that across 2D. the potential difference across 1 is half that across 2E. none of the above are true |
| Answer» BRO, OPTION no. B is CORRECT | |
| 13. |
In the circuit shown the electrical energy stored in a capacitor of capacitance 10 f in steady state is |
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Answer» eeeeeeeeExplanation:STEADY State in Capacitors: When a capacitor is connected to a voltage SUPPLY in an RLC network, it starts out charging and then at some point the voltage across the capacitor remains CONSTANT at a maximum value CONSISTENT with the supply voltage. That state is called a steady-state.hope it is correct and helps u ☺️❤️❤️ |
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| 14. |
Of a particle is position given by 7 = (31 1+ 41 3+ sky m. Find the velocity and acceleration of the particle (ü) The magnitude of velocity and acceleration of particle at 1=5 s. (Ans.(m) (3 i+ 1212 Àmst, a = 241 j ms? (ii) u = 300 m st. a = 120 m 52) |
| Answer» TION:jsjsjxudidkkdjdkfkf | |
| 15. |
what happens to the resistance of an alloy when the temperature is increased and what would happen if the temperature is decreased? ???why this happens???? |
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Answer» tion:Their movement controls by defects.One of defects of usual metal isoscillations of atoms due totemperature. More temperature - moreoscillations - more collisions ofelectrons with atoms - LESS mobilitymore resistivity. ... That is why alloyshave no temperature dependence ofresistivity.Decreasing TemperatureIf you decrease the temperature of afixed amount of gas at constantpressure, the COMBINED gas lawreduces to Charles's law. In this CASE,VOLUME will also decrease. |
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| 16. |
. he of a position particle is given by (3t i + 412 j+ 5 Â) m. Find () the velocity and acceleration of the particle (ii) The magnitude of velocity and acceleration of particle at t= 5 s. (Ans. (1) (3 + 1272 î) ms!, à = 24t) ms-2 (ii) u = 300 m s-1, a = 120 m s-2) |
| Answer» ANSWER is GIVEN Below the QUESTION ...... | |
| 17. |
Explain me resistance in Series and resistance in parallel |
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Answer» tion:a SERIES circuit, the OUTPUT current of the first resistor FLOWS into the input of the SECOND resistor; therefore, the current is the same in each resistor. In a parallel circuit, all of the resistor leads on ONE side of the resistors are connected together and all the leads on the other side are connected together. |
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| 18. |
Find the unit vector perpendicular to the plane containing the vectors ] = (41+ 21 - k) and Q = (3î – ĵ + k). Also find the area of the parallelogram formed by the two vectors. |
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Answer» We know that a×B is VECTOR perpendicular to the plane of a and bTherefore unit vector perpendicular to the plane of a and b = ∣a×b∣a×b Now a×b=(2i−j+K)×(3i+4j−k)= ∣∣∣∣∣∣∣∣ i23 j−14 k1−1 ∣∣∣∣∣∣∣∣ =i(1−4)+j(3+2)+k(8+3)=−3i+5j+11k⇒ unit vector PARALLEL to a×b= ∣a×b∣a×b = (3 2 +5 2 +11 2 ) −3i+5j+11k = 155 −3i+5j+11k |
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| 19. |
Derive a relationship between mechanical advantage, velocity ratio and efficiency of a machine. (class 10) |
| Answer» TION:HOPE its HELP you and it is the CORRECT ANSWER | |
| 20. |
Integrate : 7-2x+3x²limits from 0 to 5 |
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Answer» 73Explanation:I HOPE this can SOLVE your PROBLEM..The ANS is 73. |
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| 21. |
The two masses m1 and m2 are dropped simultaneously from 100 m & 400 m heights respectively, what is the ratio in their time taken to reach on ground?. |
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Answer» The ANSWER is 1/2, INDEPENDENT of MASS |
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| 22. |
Under the action of a force, a 2 kg body moves such that its position x=t^2/3 x is a function of time t is given by - where xis in metre and tinsecond. The work done by the force in first two seconds is |
| Answer» SRY the QUESTION is not CLEAR | |
| 23. |
A ray of light travelling in air is incident on the surface of a plastic slab at an angle. If the angle ofrefraction is 30°, and the refractive index of theplastic is 3, find the angle of incidence. |
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Answer» llllllllllllllll |
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| 24. |
Someone pls tell if it's correctly drawn or not NaCl by weight : 1,3,4,6,8,10,11,12,13,14Density :1.007,1.021,1.028,1.043,1.059,1.075,1.082,1.089,1.097,1.104 |
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| 25. |
A car is moving with 10m/s speed having 135J kinetic energy. Calculate the mass of the car. |
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Answer» 27gExplanation:K. E=1/2mv squareBy rearrangingm=2K.E/vBy PUTTING valuesm=2(135)/10m=27g |
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| 26. |
A train has schedul speed of 30 kmph over a level track ,distance between station being 1km station stopping time is 2o second.Assuming braking retandation of 3 km phps and maximum speed 25% greater then average speed .calculate the acceleration frequency run with service ? |
| Answer» PLEASE MARK me BRAINLIEST | |
| 27. |
when two resistor are connected in parallel of 6 ohms and 4 ohms and the potential difference applied is 220 volt so what is the total current flowing in the circuit? |
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Answer» e-pdzplease COME |
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| 28. |
Plss help me out in ohysics numericals no scam question no b |
| Answer» SORRY yarr i dont intrested in phisics NUMERICAL i m rely SORY | |
| 29. |
If 1500J is work done in 2 minutes. Calculate the power. |
| Answer» 3000.. HOPE it will HELP you .. | |
| 30. |
Please solve the question in the picture. plz answer quickly.Best answer will be marked brainliest |
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Answer» ာာိြနငသို့ခာနူတသသန၈၃ညမာာိာညိညိုျစ၂င၂ညိာျExplanation:ိြု်ုမုုမငါငင်ုတစသသန၈ငိကိပ်ြ်ညို၁သ ငြ်ု၁စ၉၃၈ငယ |
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| 31. |
A sample of gold has a mass of 38.6 grams and a volume of 2 cm3. What is the density of gold? Part B A sample of iron has a mass of 46.8 grams and a volume of 6 cm3. What is the density of iron? Part C Of the two samples described in parts A and B, the sample of iron has more mass and feels heavier than the sample of gold. Does this mean that the density of iron is greater? Explain. Part D Water has a density of 1.0 g/cm3. What is the mass of 10.0 cm3 of water? Part E Some substances have the same chemical composition, but their atoms are arranged differently. A classic example is carbon. A pencil lead is made of graphite, which contains only carbon atoms. A diamond also contains only carbon atoms. However, the carbon atoms in a diamond are packed more closely together. Would you expect the density of graphite and a diamond to be the same? Explain your answer. |
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| 32. |
V-t graph of particle mass 3 kg moving as in figure. the work done by all forces acting on particle in time 3s a)+1800b)+3200c)-1800d)-3200 |
| Answer» MUJE mera nahi aata BHAIYA AAPKA khana SE bataungi | |
| 33. |
A man throws a ball of mass 0.4kg vertically upwards with a velocity of 10m/s. What will be it’s initial momentum? What would be it’s initial momentum at the highest point of its reach? |
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Answer» 0Explanation: |
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| 34. |
What is meant by x volts voltage at a point of a electric field |
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Answer» Electric potential at a POINT is 1 VOLT SIMPLY means that if SOMEONE wants to move a "1 coloumb" +ve charge from ∞ to that point, we will have to PERFORM a work equal to 1 Joule. |
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| 35. |
How long does it take a Ruby-throated hummingbird to fly across the Gulf of Mexico (500 miles) if its average flight speed is 30 mph? |
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Answer» Time taken by a hummingbird to fly 30 miles = 1 hourTime taken by a hummingbird to fly 500 miles to the GULF of MEXICO = = 500 ÷ 30 = 16.666 hours Therefore , a hummingbird TAKES 16.666 hours to fly 500 miles towards the Gulf of Mexico .Hey dear hope you find my answer useful!! |
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| 36. |
Why helicopter has two propellers |
| Answer» TION:Have you ever thought why some helicopters have two propellers? The MAIN rotor creates lift by re-directing the FLOW of AIR downward. ... Therefore torque tends to turn the aircraft in one way and the tail rotor's thrust opposes this. To turn the helicopter in the OPPOSITE way, the tail rotor thrust is reduced | |
| 37. |
What is wave particle duality and unified field theory in detail |
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Answer» hope it helps... Explanation:Wave–PARTICLE duality is the CONCEPT in quantum mechanics that every particle or quantum entity may be described as either a particle or a wave. It expresses the INABILITY of the classical concepts "particle" or "wave" to fully describe the behaviour of quantum-scale objects. |
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| 38. |
What is the geometrical shape of equipotential surfaces due to a single isolated charge? |
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Answer» Because, the FIELD lines spread out in all direction originating from the point in space where the single isolated charge has been KEPT, CLEARLY, since the electric field lines have to be normal to the equipotential surfaces, clearly in THREE DIMENSIONS, this equipotential surface will have a spherical shape. |
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| 39. |
In LCR series circuit the sharpness of the resonance at a given frequency can be increased by |
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Answer» The SHARPNESS of RESONANCE increases with an INCREASE in damping and decreases with a DECREASE in damping. |
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| 40. |
열 The wave function offree particle at timet=0 is given by: P (2,0)=0 inseby: Y(2,0) = 0 ne herThe function 0(n) is real and differs gnificantfrom zero Only for values of lyingpe in theinterval-scals.For which range of Values Alle will theWave function atdifferent from Zero?later time t be significantly |
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Answer» 열 by the way WHATS this?Explanation:This is the equation for a (non-relativistic) particle of mass m moving along the x axis whileacted by the potential V (x,t) ∈ R. It is clear from this equation that the wavefunction mustbe complex: if it were real, the right-hand side of (1.2) would be real while the left-hand sidewould be imaginary, due to the explicit factor of i.Let us make two important remarks:1 1. The Schr¨odinger equation is a first order differential equation in time. This means that ifwe prescribe the wavefunction Ψ(x,t0) for all of space at an arbitrary initial time t0, thewavefunction is determined for all times.2. The Schr¨odinger equation is a linear equation for Ψ: if Ψ1 and Ψ2 are solutions so isa1Ψ1 + a2Ψ2 with a1 and a2 arbitrary complex numbers.Given a complex number z = a + IB, a, b ∈ R, its complex conjugate is z∗ = a − ib. Let|z| denote the NORM or length of the complex number z. The norm is a positive number (thus√ real!) and it is given by |z| = a2 + b2 . If the norm of a complex number is zero, the complexnumber is zero. You can quickly verify that∗ |z|2 = zz . (1.3)For a wavefunction Ψ(x,t) its complex conjugate (Ψ(x,t))∗ will be usually written as Ψ∗(x,t).We define the probability density P(x,t), also denoted as ρ(x,t), as the norm-squared ofthe wavefunction:P(x,t) = ρ(x,t) ≡ Ψ∗(x,t)Ψ(x,t) = |Ψ(x,t)|2 . (1.4)This probability density so defined is positive. The physical interpretation of the wavefunctionarises because we declare thatP(x,t) dx is the probability to find the particle in the interval [x, x + dx] at time t .(1.5)This interpretation requires a normalized wavefunction, namely, the wavefunction used abovemust satisfy, for all times, ∞dx |Ψ(x,t)|2 = 1 , ∀ t . (1.6) −∞By integrating over space, the left-hand adds up the probabilities that the particle be foundin all of the tiny intervals dx that comprise the real line. Since the particle must be foundsomewhere this sum must be equal to one.Suppose you are handed a wavefunction that is normalized at time t0: ∞dx |Ψ(x,t0)|2 = 1 , ∀ t . (1.7) −∞As mentioned above, knowledge of the wavefunction at one time implies, via the Schr¨odingerequation, knowledge for all times. The Schr¨odinger equation must guarantee that the wavefunction remains normalized for all times. Proving this is a good exercise:2 - - - - - - - - - - - - - - -Exercise 1. Show that the Schr¨odinger equation implies that the norm of the wavefunctiondoes not change in time:d ∞dx |Ψ(x,t)|2 = 0 . (1.8) dt −∞You will have to use both the Schr¨odinger equation and its complex-conjugate version. Moreoveryou will have to use Ψ(x,t) → 0 as |x| → ∞, which is true, as no normalizable wavefunctioncan take a non-zero value as |x| → ∞. While generally the derivative ∂ Ψ also goes to zero as ∂x|x| → ∞ you only need to assume that it remains bounded.Associated to the probability density ρ(x,t) = Ψ∗Ψ there is a probability current J(x,t)that characterizes the flow of probability and is given by∂ΨJ(x,t) = Im Ψ∗ . (1.9) m ∂xThe analogy in electromagnetism is useful. There we have the current density vector Ji and thecharge density ρ. The statement of charge conservation is the differential relation∇ · Ji + ∂ρ = 0 . (1.10) ∂tThis equation applied to a fixed volume V implies that the rate of change of the enclosed chargeQV (t) is only due to the flux of Ji across the surface S that bounds the volume:i dQV i (t) = − J · dia . (1.11) dt SMake sure you know how to get this equation from (1.10)! While the probability current inmore than one spatial dimension is also a vector, in our present one-dimensional case, it hasjust one component. The conservation equation is the analog of (1.10):∂J ∂ρ + = 0 . (1.12) ∂x ∂tYou can check that this equation holds using the above formula for J(x,t), the formula forρ(x,t), and the Schr¨odinger equation. The integral version is formulated by first defining theprobability Pab(t) of finding the particle in the interval x ∈ [a, b]b bPab(t) ≡ dx|Ψ(x,t)|2 = dx ρ(x,t). (1.13) a aYou can then quickly show thatdPab (t) = J(a,t) − J(b,t). (1.14) dt3Z~ Z ZHere J(a,t) denotes the rate at which probability flows in (in units of one over time) at the leftboundary of the interval, while J(b,t) denotes the rate at which probability flows out at theright boundary of the interval.It is SOMETIMES easier to work with wavefunctions that are not normalized. The normalization can be perfomed if needed. We will thus refer to wavefunctions in general without assumingnormalization, otherwise we will call them normalized wavefunction. In this spirit, two wavefunctions Ψ1 and Ψ2 solving the Schr¨odinger equation are DECLARED to be physically equivalentif they differ by multiplication by a complex number. Using the symbol ∼ for equivalence, wewriteΨ1 ∼ Ψ2 ←→ Ψ1(x,t) = α Ψ2(x,t), α ∈ C . (1.15)If the wavefunctions Ψ1 and Ψ2 are normalized they are equivalent if they differ by an overallconstant phase:Normalized wavefunctions: Ψ1 ∼ Ψ2 ←→ Ψ1(x,t) = eiθ Ψ2(x,t), θ ∈ R . |
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| 41. |
2 copper wires has length in ratio 2:1 and area of cross section in ratio 1:2 ,then their specific resistance will be in ratio |
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| 42. |
Derive ohm's law with the help of diagram. |
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Answer» : Ohm’s law states that the voltage or potential difference between two points is directly proportional to the current or electricity passing through the resistance, and directly proportional to the resistance of the CIRCUIT. The formula for Ohm’s law is V=IR. This RELATIONSHIP between current, voltage, and relationship was discovered by German scientist Georg Simon Ohm. Let us learn more about Ohms Law, Resistance, and its applications.Explanation: Ohm’s Law DefinitionMost basic components of electricity are voltage, current, and resistance. Ohm’s law shows a simple relation between these three QUANTITIES. Ohm’s law states that the current through a conductor between two points is directly proportional to the voltage across the two points. Ohm’s law states that the voltage or potential difference between two points is directly proportional to the current or electricity passing through the resistance, and directly proportional to the resistance of the circuit. The formula for Ohm’s law is V=IR. This relationship between current, voltage, and relationship was discovered by German scientist Georg Simon Ohm. Let us learn more about Ohms Law, Resistance, and its applications.Ohm’s Law DefinitionMost basic components of electricity are voltage, current, and resistance. Ohm’s law shows a simple relation between these three quantities. Ohm’s law states that the current through a conductor between two points is directly proportional to the voltage across the two points.Ohm’s Law FormulaVoltage= Current× ResistanceV= I×RV= voltage, I= current and R= resistanceThe SI unit of resistance is ohms and is denoted by ΩThis law is one of the most basic LAWS of electricity. It helps to calculate the power, efficiency, current, voltage, and resistance of an element of an electrical circuit. |
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| 43. |
A 60kg person jumps onto the floor from a height of 3.00m. If he lands stiffly (with his knee joints compressing by 0.500 cm), Calculate the force on the knee joints. |
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Answer» tion:Step 1Given:mass of person (m) = 60 kg.height of jump (h) = 3.0 m.joints compressed (x) = 0.5 cm. = 0.005 m.Step 2Person stated at height contain potential energy. when he jumps, his potential energy converts into kinetic energy and at floor the kinetic energy becomes ZERO. The work done by floor on knee of person is equal to the kinetic energy.The work done by floor is,Physics homework QUESTION answer, step 2, image 1Angle will be 180 in between FORCE and DISPLACEMENT because force exerted on knee is in upward DIRECTION and direction of displacement is downward.Step 3Change in potential energy will be equal to kinetic energy.Physics homework question answer, step 3, image 1this change in potential energy will be equal to work done.Please mark it as the brainliest |
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| 45. |
7. An object is placed at a distance of 0.8m from the combination of convex lens of focal length 0.4m and concave lens of focal length 0.5m. Find the image distance andlinear magnification.nend mice |
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Answer» autfgufchigvjjihgjiihh |
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| 46. |
State and explain the laws of reflection of light at a plane surface with the help of labeled ray diagrams. Mark angle of ‘incidence’ and ‘reflection’ clearly on the diagram. If the angle of reflection is 47.5 , what will be the angle of incidence? |
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Answer» You can conclude from this that the incident ray the reflected ray and the normal at the point of INCIDENCE LIE in the same PLANE. |
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| 47. |
Please answer with solution |
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Answer» tion:lnitial velocity of the OBJECT (u) = 10 m / sMass of the object (m) =2 kg Final velocity (v) = 0 m /s lmpuse = CHANGE in momentum=> J = mv - MU => J = m(v-u)=> J = 2 ( 0 - 10) =>J = 20 Kg m / sSo, the impulse is 20 Kg m/ s.HOPE IT HELPS. |
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| 48. |
16. FĀ= (31 + 2 + 3k) and B = (i-1 + 2k). Find the angle between A and B. |
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Answer» djjsjsjsjs djjsjsjsjs jsjsjsjeueueuwjwjjfjfjifififiejejejrjd wjjwjejejjwwy wjjwjejejjwwy the MECHANISM of ACTION for the mechanism of action for the mechanism of |
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| 49. |
Which of the following examples would diffuses the fastest A. Salt into water. Milk into water C. Sand into water D. Perfume in room |
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| 50. |
State the kepler's law in detail |
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Answer» The Law of Orbits: All planets MOVE in ELLIPTICAL orbits, with the sun at one focus. 2. The Law of Areas: A line that connects a planet to the sun sweeps out equal areas in equal TIMES. ... The Law of Periods: The square of the period of any planet is proportional to the cube of the SEMIMAJOR axis of its orbit. |
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