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.
| 1. |
What is the magnitude of horsepower in SI unit |
| Answer» SPLS MARK as BRAINLIEST ❤️❤️❤️❤️ | |
| 2. |
1. Answer the following questions : 1. The distance between two fixed positive charges 4e and e isl. How should athird charge q be arranged for it to be in equilibrium ? Under what conditionswill the equilibrium of the charge q be stabel and when will it be unstable ?2. Two free positive charges 4e and e are a distance a apart. What change isneeded to acheive equilibrium for the entire system and where should it beplaced ?3. A negative point charge 2e and a positive charge e are fixed at a distance l fromeach other. Where should a positive test charge q be placed on the lineconnecting the charges for it to be in equilibrium ? What is the nature ofequilibrium of the test charge with respect to longitudinal motions. Plot thedependence of the force acting on this charge on the distance between it and thecharge te.A charged particle is free to move in an electric field. It will travel5. Two point charges Q and -3Q are placed at some distance apart. If the electricfield at the location of Q is E then at the locality of 3Q, it is |
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Answer» Explanation:3.Let the charge Q be placed at distance x from charge 2q. Now for the charge to be in equilibrium the forces due to both charges must cancel each other or the forces must be equal and opposite. Now the forces due to each charges is given by F 2q =2kQq/x 2 and F q =kQq/(l−x) 2 for equilibrium we must have F 2q =F q or, 2kQq/x 2 =kQq/(l−x) 2 or, (l−x) 2 x 2 =2 or, l−x x = 2 or, x= 1+ 2 2 l l−x x =− 2 or, x= 2 −1 2 l Since second solution of x lies outside the l we will neglect it. Hence the answer is- $x= 2 +1 2 l $ Now if the charge is displaced longitudinally towards charge q then x will increase hence F 2q will decrease and F q will increase. Hence the charge will be forced to move towards charge q. Similarly if it is moved towards charge 2q, F 2q will increase and F q will decrease thus the charge Q will be moved towards charge 2q. Hence the charge Q is in unstable equilibrium with respect to longitudinal motions.2.Let"R" be the distance from the charge q where Q is in equilibrium .Total Force acting on Charge q and 4q:F=kqQ/r² + k4qQ/(l-r)²For Q to be in equilibrium , F should be equated to zero.kqQ/r² + k4qQ/(l-r)²=0(l-r)²=4r²⇒l-r=2r⇒l=3r⇒r=l/3Taking the third charge to be -Q (say) and then on applying the condition of equilibrium on + q chargekQ/(L/3)² =k(4q)/L²9kQ/L²=4kq/L²9Q=4qQ=4q/9Therefore a point charge -4q/9 should be placed at a distance of L/3 RIGHTWARDS from the point charge +q on the line joining the 2 charges.1.Given,qA = +4eqB = +eAB = xLet, Q be the third point charge located at some point P.AP = xtherefore, PB = (a-x)Force on Q due to qA,F1 = kqAQ/x2Force on Q due to qBF2= kQqB/(a-x)2Since the charge is in equilibrium,F1 = F2kqAQ/x2 = k qBQ/(a-x)24e/x2 = e/(a-x)24/x2 = 1/(a-x)2 (Taking square ROOT on both sides)2/x = 1/(a-x)2(a-x) = x(1)2a - 2x = x2a = 3xx = 2/3aTherefore, the third point charge Q should be placed 2/3a from A.if helps mark as brainlist answer |
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| 3. |
ACROSS 2 What chemical reaction is performed by F?4. The chemical reactionperformed by A.5. Identify P in the diagram.6. Identify H in the diagram.11. Identify G in the diagram.15. Identify F in the diagram.16. The liquid substance contained within B.19. Identify j in the diagram.22. Identify Q in the diagram.23. Identify L in the diagram.24. Identify E in the diagram.DOWN1. Identify A in the diagram.3. Identify M in the diagram.7. Identify I in the diagram.8. Identify D in the diagram.9. What content is contained within K.10. Another name for D12. The area of the cell indicated by B13. Another name for J.14. Identify K in the diagram.17. The plural of A19. Besides proteins, what else is found within G.20. Identify O in the diagram.21. Identify C in the diagram. |
| Answer» SORRY FRIEND this is very LONG | |
| 4. |
11. A convergent beam of light converges to a point 20 cm behind the convex mirroron the principal axis. An inverted imageof the same size is formed coincidentwith the virtual object. Then, the focallength of the convex mirror is1) 20 cm2) 10 cm3) 40 cm4) 30 cm |
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Answer» teExplanation:Here, the point at which the BEAM would have converged in absence of the lens acts as VIRTUAL object. So,u=+20cm.Again since the image is INVERTED and of same size, m=−1.∴m=−1=uv⇒v=−20cm∴f1=v1−u1=−201−201=20−2=10−1.I hope this will HELP you❤️❤️ |
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| 5. |
Who will say correct answer I will mark as brainliest |
| Answer» 1) wavelength 2)no.of neutrons3)15 electrons4)Zn 56 is not there Zn 65 has 30 neutrons5) 11:11:12 | |
| 6. |
Two cars moving in the same direction with velocities 12 m/s and 9 m/s respectively. What is the relative velocity of the car A with respect to the car B ? If both the cars are travelling in opposite directions, what will be the relative velocity ? Topic-Velocity and Acceleration |
| Answer» 21 m/sExplanation:Vab = VA - VB =12I^ - (9i^) =12i^ + 9i^ =| 21i^ | =21 m/s | |
| 7. |
Each side of a cube is measured to be 5.402cm in appropriate significant digits. |
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Answer» bro cube ki SIDE toh de diExplanation:YE toh BATA do KYA KARNA hai volume likalni hai ya area |
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| 8. |
Pls answer its urgent |
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Answer» For the first CIRCUIT the answer is 5/7 ohm.RESISTANCES 3 and 2 ohm are in series while the resultant resistance of these and 1 ohm are in parallelFor the second circuit the answer is 24/5 ohmExplanation:resistances 8,9,7 ohm are in series while it's resultant and 6 ohm are in parellel |
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| 9. |
V is equal to logx then find E at x is equal to-1 |
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Answer» 1 V/mExplanation:GIVEN V= log XAS we know E = -(dv/dx,)DERIVATIVE of log x is 1/x HENCE the value of derivative @ x= -1 is 1 V/m or 1 N/C |
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| 10. |
If the density of wood is 0.5 g/cm what is the mass of 10cm3 |
| Answer» MASS = Density × VOLUME Mass = 0.5 × 10mass = 5gExplanation:HOPE the answer will help you | |
| 11. |
Light independent reaction: :Biosynthetic phase:: light dependent reaction:............................... |
| Answer» LIGHT dependent REACTION also known as PHOTOCHEMICAL reaction.Explanation:hope the answer will HELP you | |
| 12. |
(i) Find ∆× =? (ii) Draw x•t graph |
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Answer» ∆x = 18 mx-t graph will STRAIGHT line straight line from originExplanation:Area under v-t CURVE GIVES XA straight line from origin in x-t curve DENOTES constant velocity |
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| 13. |
Derive the equation S=ut+1/2at² using Dimensional Analysis |
| Answer» TION:derive the equation S=ut+1/2at² using DIMENSIONAL ANALYSIS... it's not TIME | |
| 14. |
Plz answer and spammers keep away or I will report you if you know tell |
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Answer» The man who CLIMBS the slope.Explanation:b'coz work equals to FORCE x distanceand as he climbs up for E of gravity is exerted more.Mark as Brainliest |
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| 15. |
Each side of a cube is measured to be 5.402cm in appropriate significant digits.pls ans it... |
| Answer» DE of a cube is MEASURED to be 5.402cm in APPROPRIATE significant digits.pls ANS it... SORRY ...xd I dont know✌✌✌✔✔☝✔✌Mark brainlist☝☝✴✔✔ | |
| 16. |
Is absolute rest possible? give reason? |
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Answer» The concept of "relative rest" is closely linked to that of inertial observers and the statement that "nothing is at ABSOLUTE rest" is loosely equivalent to stating that there are no frames of reference which are TRULY inertial. So-called non-inertial observers are ADDRESSED by the theory of general relativity.Explanation:FOLLOW me.. |
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| 17. |
The refractive indices of flints glass prism for C,D and F lines are and respectively . Find the dispersive power of the flint glass prism. |
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Answer» the question of whether you have any questions or need any further information PLEASE contact me at the end of the MONEY to pay 57 CDS |
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| 19. |
20 x 2 OYSt 59. Two capacitors A and B rated at (10 uF -1101)zeand (20uF - 110V) respectively are connectedhein parallel to 220V source. Which one is likelyisto be damanged1. A capacitor 2. B capacitorhe3. Both A and B4. None |
| Answer» SEARCH on GOOGLE DOST OK | |
| 20. |
Draw a ray diagram shows the formation of the image of a point object placed above the principal axis of a convex mirror |
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Answer» here's your ANSWEREXPLANATION:HOPE it works PLEASE mark it as BRAINLIST |
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| 21. |
Refraction through glass slab is shown in the diagram.The correct emergent ray is .........(A) A (B) B (C) C (D) All of these |
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| 22. |
Find effective resistance of the network |
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Answer» effctive RESISTANCE 2 is a RIGHT ANSWER |
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| 23. |
Problem 2.2 (a) Find the electric field (magnitude and direction) a distance z above the midpoint betweentwo equal charges, 9, a distance d apart (Fig. 2.4). Check that your result is consistent withwhat you'd expect when z >> d.(b) Repeat part (a), only this time make the right-hand charge - instead of +q.2P•РŹdgPdi'(b) Line charge, a(a) Continuousdistribution•Рda'2 Pdi'9 d/2d/29(c) Surface charge, o(d) Volume charge, pFigure 2.4Figure 2.5 |
| Answer» ANSWER: Answer: Answer: L=2m,Answer: L=2m,d=3mm,A= Answer: L=2m,d=3mm,A= 4ANSWER: L=2m,d=3mm,A= 49πAnswer: L=2m,d=3mm,A= 49πAnswer: L=2m,d=3mm,A= 49π ×10 Answer: L=2m,d=3mm,A= 49π ×10 −6Answer: L=2m,d=3mm,A= 49π ×10 −6 m Answer: L=2m,d=3mm,A= 49π ×10 −6 m 2ANSWER: L=2m,d=3mm,A= 49π ×10 −6 m 2 Answer: L=2m,d=3mm,A= 49π ×10 −6 m 2 ΔL= Answer: L=2m,d=3mm,A= 49π ×10 −6 m 2 ΔL= 4Answer: L=2m,d=3mm,A= 49π ×10 −6 m 2 ΔL= 49πAnswer: L=2m,d=3mm,A= 49π ×10 −6 m 2 ΔL= 49πAnswer: L=2m,d=3mm,A= 49π ×10 −6 m 2 ΔL= 49π ×10 Answer: L=2m,d=3mm,A= 49π ×10 −6 m 2 ΔL= 49π ×10 −6Answer: L=2m,d=3mm,A= 49π ×10 −6 m 2 ΔL= 49π ×10 −6 ×10 Answer: L=2m,d=3mm,A= 49π ×10 −6 m 2 ΔL= 49π ×10 −6 ×10 11Answer: L=2m,d=3mm,A= 49π ×10 −6 m 2 ΔL= 49π ×10 −6 ×10 11 Answer: L=2m,d=3mm,A= 49π ×10 −6 m 2 ΔL= 49π ×10 −6 ×10 11 30×2Answer: L=2m,d=3mm,A= 49π ×10 −6 m 2 ΔL= 49π ×10 −6 ×10 11 30×2Answer: L=2m,d=3mm,A= 49π ×10 −6 m 2 ΔL= 49π ×10 −6 ×10 11 30×2 =8.48×10 Answer: L=2m,d=3mm,A= 49π ×10 −6 m 2 ΔL= 49π ×10 −6 ×10 11 30×2 =8.48×10 −5Answer: L=2m,d=3mm,A= 49π ×10 −6 m 2 ΔL= 49π ×10 −6 ×10 11 30×2 =8.48×10 −5 m=0.085mmAnswer: L=2m,d=3mm,A= 49π ×10 −6 m 2 ΔL= 49π ×10 −6 ×10 11 30×2 =8.48×10 −5 m=0.085mm Answer: L=2m,d=3mm,A= 49π ×10 −6 m 2 ΔL= 49π ×10 −6 ×10 11 30×2 =8.48×10 −5 m=0.085mm .Answer: L=2m,d=3mm,A= 49π ×10 −6 m 2 ΔL= 49π ×10 −6 ×10 11 30×2 =8.48×10 −5 m=0.085mm . Answer: L=2m,d=3mm,A= 49π ×10 −6 m 2 ΔL= 49π ×10 −6 ×10 11 30×2 =8.48×10 −5 m=0.085mm . | |
| 24. |
resultant of two equal forces acting perpendicular to each other is 144 n. what is the magnitude of each force? |
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Answer» y the VECTOR LAW of ADDITION of FORCES, 144² = F² + F² F = 144/√2 = 72√2 Newtons |
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| 25. |
two forces whose magnitudes are in ratio 3:5 give a resultant equal to 49N, if the angle of inclination is 60 degree, find the magnitude of each force |
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| 26. |
Match the following section A with section B 1)hydraulic lift a)charge is zero 2)purity of gold b)net charge is zero3)acceleration c)pascal's law4)energy d)archimede's principle5)neutral charge e)scalar quantity f)vector quantity |
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Answer» aulic lift a) charge is zero2) PURITY of gold b) net charge is zero3) acceleration c) pascal's law4) energy d) Archimedes principle5) neutral charge E) scalar QUANTITY f) vector quantity2 - d Archemedes discovered the law, to find the purity of gold in the crown.1 - c Pascal's law - pressure is same at the same height in a liquid. this is used to lift very heavy loads by hydraulic lift.3 - f 5 - b uncharged particle means charge is 0. neutral charge means that there are EQUAL and opposite charges present on a body or at a location.4 - e |
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| 27. |
Solve these numericals:- (PLEASE HELP, URGENTLY NEEDED!) 1) A stone is dropped from a tall building of 80 metres height. Find its final velocity and the time taken to touch the ground (take g = 10 metres per second square). 2) A car initially at rest starts moving with an acceleration of 0.5 metres per second square and travels a distance of 25 metres. Calculate its final velocity and its time. |
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Answer» s = 80 m = displacement u = 0 = initial velocity g = 10 m/sec/sec acceleration of the STONE equation of motion : v² = u ² + 2 a s v² = 0 + 2 * 10 * 80 = 1600 v = final velocity = 40 m/sec2) u = 0 a = 0.50 m/sec/sec s = 25 m v² = u² + 2 a s = 0 + 2 * 0.4 * 25 = 20 v = √20 m /sec = 2 √5 m/s v = u + a t t = (v - u) / a = 2√5 / 0.50 = 4 √5 seconds. |
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| 28. |
If speed is plotted along x-axis and Kinetic energy against y-axis, then the graph obtained has a shape similar to that of A. circle B. ellipse C. hyperbola D. parabola |
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| 29. |
If speed is plotted along x-axis and Kinetic energy against y-axis, then the graph obtained has a shape similar to that of A. circle B. ellipse C. hyperbola D. parabola |
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Answer» be a PARABOLA.let speed = xkinetic energy = y = 1/2 m x²the shape of this CURVE is a parabola, as it is in the form: x² = 4 a y The curve is ALWAYS above x axis. The axis of the parabola is x = 0 or the y axis. the directrix of parabola is at y = - 1/(2m) |
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| 30. |
Convert the force on body of mass 55 N into dynes |
| Answer» N= 10 to the POWER 5 dynesooo 55 newton=55 ×10 to the power 5 | |
| 31. |
when 2 bodies are rigidly connected to a string, say, m1 and m2, do they have the same acceleration or different? don't consider the direction of the acceleration, just the magnitude. PLEASE BE SURE AND ANSWER. thank you :) |
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Answer» string is rigid , tight, inextensible with tension > 0, then the two bodies have the same (magnitude of) ACCELERATION, along the direction of the string on either side. If the string is loose or folded, then the accelerations cannot be inter-related easily.I SUPPOSE there is no rotation of the two bodies..Is this question / DOUBT from the TOPIC pulleys, bodies attached to strings rolling over pulleys? Then yes, certainly. |
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| 32. |
When current gain and emittor current are given how to calculate base current |
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Answer» related to bipolar junction transistor in the common EMITTER configuration. The CURRENT GAIN is defined as α, which is usually around 50. A small DC current in the base of the transistor triggers a high current in the collector region which flows TOWARDS the emitter. The base is less dop ed and collector is heavily dop ed with impurities.Current gain = collector current / base current = [ emitter current - base current ] / base current = emitter current / base current - 1base current = emitter current / [ current gain + 1 ] |
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| 33. |
Look at the attachement and answer the questyions |
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Answer» T Cos 30 = 1 kg * a 30 N - T cos 30 = 2 kg * a => 3 a = 30 => a = 10 m/sec/sec => T = 20/√3 N Normal reaction: mg - T sin 30 = 1 * 10 - 20/√3 * 1/2 = 10 - 10/√3 N===========15. m1 = 2 kg m2 = 5 kg F - (m1 + m2) g = (m1 + m2 ) a => F - 70 = 7 a So the pulley moves up only if F > 70 NEWTONS. F = 70 N, then accelerations are both 0, as the pulley still does not move up.=======================16. m2 g = tension as m2 is at rest. m1 g Sin Ф - tension as m1 is at rest. m1 Sin Ф = m2 verify the options by substitution.=======17 F1 = 10 N, F2 = 20 N F1 Cos 60 + F2 = 25 N --- in x direction F1 Sin 60 = 5√3 N --- in the y direction, as block is at rest. resultant = √ [25² + (5√3)² ] = 26.46 N the result is supposed to be an integer???/ Are you expected to write only the force in the x direction ???==============18. m1 = 3 kg, m2 = 2kg F cos 60 = m1 a - T T = m2 a a = F * Cos 60 /(m1+m2) = 1 m/s/s T = 2 N===============19. F - mg = ma F - 2 * 10 = 2 * 5 F = 30 N==================20. F - mg = m a = - m g as F is upwards, and a = -g downwards F = 0 N |
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| 34. |
Look at the attachement and asnwer the questions |
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Answer» Normal force on B by the floor = F Force exerted by block A on B: F1 F - m_B g - F1 = - m_B * 2 => F = F1 + m_B g - 2 m_B F1 - m_A g = - m_A * 2 => F1 = g/2 - 1 = 4 Newtons =======================9. component of weight/acceleration due to gravity along the inclined slope = g Sin 30 = g/2 Component of weight/acceleration along the groove OA = g/2 Sin 30 = g/4 s = u t + 1/2 a t² => t² = 2 s / a t² = 2 * 5 / (g/4) = 4 => t = 2 sec.=================10. m1 = 100 kg M2 = 60 kg a1 = acceleration of 100 kg upwards. Rope is also moving with the same acceleration. T - 100 kg * g = 100 kg * a1 => T = 1000+ 100 a1 ---- (1) Acceleration of the person = a relative acceleration of the man wrt rope = a + a1 = 5g/4 => a = 5g/4 - a1 = 12.5 - a1 upwards T - 60 kg * g = 60 kg * a T = 600 + 60 a = 600 + 60 (12.5 - a1) = 1350 - 60 a1 ----- (2) Solving the two equations a1 = 350/160 m/sec/sec T = 1000 + 100 * 35/16 = 1218 N======================11 F = buoyancy force upwards remains same F - M g = M a => F = M (g+a) F - (M-m) g = (M-m) a' => a' = [ M g + Ma - Mg + mg ] / (M-m) a' = (M a + m g)/(M-m)===============================12. T - 5 g = 5 a 10 g - T = 10 a a = g/3================= 13. F - m g Sin 37 = m a along the slope 5.5 - 0.50 * g * 0.6 = 0.50 a => a = 5 m/sec/sec v^2 = 2 a s = 2 * 5 * 10 = 100 v = 10 m/s at the TOP of the incline. ANGLE of projection = 37 deg. y initial = 10 Sin 37 = 6 meters Time to REACH the top point : u Sin 37 / g = 10 * 0.6 / 10 = 0.60 sec height reached = s = u sin 37 * 0.60 - 1/2 * 10 * 0.60^2 = 10 * 0.6 * 0.60 - 5 * 0.60^2 = 1.80 meters total height at the top of the flight = 6 + 1.80 = 7.80 m time to reach the ground = t => t^2 = 2s / g => t = 2 * 7.80 / 10 = 1.56 sec total time of the flight = 2.16 sec. total horizontal distance travelled after projection from the ramp = u cos 37 * 1.56 sec = 12.48 meters |
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| 35. |
When the speed of the ball is doubled what happen to kinetic energy ? |
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Answer» ball=1/2mv²when speed or velocity is DOUBLED i.e. 2vtherefore NEW K.E=1/2m(2v)² =4 × 1/2mv²Hence, the new K.E becomes 4 TIMES the EARLIER K.E. |
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| 36. |
Why is weightlessness felt at certain points in a roller coaster ????? |
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Answer» are GOING on an inclined line on a slope on a ROLLER coaster, the chair or the floor exert a force on us to balance the weight due to gravitation of Earth. When the reaction force acts on our feet or our buttocks or back, that pressure and sensation makes us feel the our weight. When we go through a vertical loop we are going in a circular arc. At the top of the roller coaster (inverted U arc), a force called centripetal force is required to make us go in a circle. This force depends on the speed, the radius of curvature and our mass. our weight = Normal reaction of the floor/chair + centripetal force normal reaction of the floor or chair = our weight - centripetal forceSo the apparent weight is reduced by the centripetal force. So the contact between our feet or BODY with the roller coaster becomes very LIGHT. So we feel weightlessness.====================Also at some points, there is a near free-fall of the persons on a roller coaster. Then the apparent weight we feel = our weight - m * acceleration of the free fall.So our apparent weight reduces a lot, when we MOVE down a slope with a large acceleration. |
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| 37. |
If A bar . B bar = A bar *B bar then angle between a bar and b bar is A)0 B)pi/4 C)pi/2 D)pi |
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Answer» here A and B MEANS A and B VECTORA B cosФ=A B sinФsinФ/cosФ=1tanФ=1tanФ=tanπ/4Ф=π/4 |
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| 38. |
what is the role of spherical mirrors in developing human civilisation?Explain in not less than 5 pages or send the link to my account .i need to submit it by tomorrow plz help me........ |
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| 39. |
Why the velocity is relative but acceleration is absolute? |
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Answer» y is defined as CHANGE of DISPLACEMENT per unit time. Usually velocity is measured with respect to an inertial frame of reference, ie., a coordinate system which does not move. So we choose the distant star in the universe which is stationary as the reference, and measure all velocities WRT to it. In our world we measure velocities wrt objects that are stationary on Earth. So velocity is measured as a relative quantity.Acceleration is defined as change of velocity per unit time. That is a = (v - u) / Δtlet v and u be measured relative to a frame of velocity v₀. Then the absolute velocities of an OBJECT at two points of time are: v + v₀ and u + v₀ respectively. Then acceleration a = [v + v₀ - u - v₀ ] / Δt a = (v - u) / ΔtThus acceleration is absolute, whether we TAKE absolute velocities or relative velocities of a particle to compute it. |
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| 40. |
Write about uniform and non uniform motion |
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Answer» rm motion - when ANYTHING covers EQUAL distances in equal intervals of time and travels in a straight line it is said to be in UNIFORM motion. like 3 km in 1 hr and 6km in 2hrs 2)non-uniform motion-when an object doesn 't travels in straight line and covers unequal distance it is called non-uniform motion.like 3KM in 1 hr and 7 km in 2 hrs Press thank you!!!! |
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| 41. |
How to balance the chemical equations? |
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Answer» nce CHEMICAL equation there r 4 steps 1)first write chemical formula in words2)then write the FORMULA3)check the formula WHETHER the coefficients are correct4)finnaly verify the formula |
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| 42. |
What is the area of pedestal of buddha statue in hussain sagar lake |
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Answer» strange question to ask... the height of Buddha statue : 18 meters and 350 tons heavy. it is made of rock of WHITE granite. The PEDESTAL is the rock (rock of GIBRALTAR) on which the statue is standing. A concrete platform of about 4 and half meters wide 4 and 1/2 meters LONG is constructed under the pedestal. |
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| 43. |
What exactly is fleming's left hand rule in thermionic emissions |
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Answer» 's left hand RULE principle is used in DC motor where the three FINGERS are perpendicular to each other where the thumb indicates direction of force ,index finger indicates induced current & middle finger indicates the magnetic INDUCTION |
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| 44. |
Two simple pendulums of length(l) are suspended from a ceiling(their strings are parallel). Their bobs, each of mass(m), are connected with a rubber string of force constant k. Assume the bobs are pulled away from each other, only by a little, so that the rubber band is stretched. When they are released simultaneously, what would be the time-period of each bob? (Neglect gravity between bobs and air resistance, and assume that the rubber string obeys Hooke's law, activity is performed in place with acceleration due to gravity, g.) |
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Answer» see diagram.The pendulums are each displaced by an amount x. The string is stretched by 2x totally. The restoration force in the spring = F2 = k * 2x = 2k x. (Hooke's law). Bob's displacement X in the tangential direction to the string = X x = displacement in the horizontal direction = X Cos Ф x = L sin Ф mg CosФ = Tension T in the string F1 = COMPONENT of weight along the tangential direction F1 = mg SinФ = m g x / L Net force on the bob = F = m a = - m * d²X / dt² (-ve sign is because the force is in the decreasing x direction) X = x / cos Ф = L tan Ф ≈ L Sin Ф ≈ L Ф, approximation for small Ф. Net force on pendulum in the tangential direction = F1 and F2 are at an angle Ф, and their vector sum is to be calculated for the resultant force and acceleration. But since Ф is small, we approximate the resultant force to be along horizontal direction and F1 and F2 along this direction. So we take the linear sum for simplicity. a = - d² X / dt² ≈ - d² x / dt² => - m d² x / dt² = 2k x + m g x/L Resultant force on the bob = mg x/L + 2 k x = F = m a = - m d^2 x/dt^2 d² x/dt² = - (g/L + 2k/m) x The equation of motion above indicates that for small amplitudes x and displacements, the pendulum oscillates in a SHM and the corresponding Angular VELOCITY = ω = √(g/L + 2k/m)= TIME period = ======================================If displacements are large then, the resultant force F will be:.. |
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| 45. |
18j work is done in moving a positive charge of 3C between 2 points . find the potential difference between the two points |
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Answer» 3CWork done=18JAs we KNOW that V=W/q=18/3=6V |
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| 47. |
What is meant by retrograde motion ? |
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Answer» ade MOTION is the motion in the DIRECTION OPPOSITE to the movement of something else and the CONTRARY or DIRECT motion |
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| 48. |
Why the electiricy move on the opposite direction to the charge or electrons? |
| Answer» MAGNITUDE of the electricity depends upon the negatively charged IONS wer more charged so due to the gravity they move OPPOSITE sides | |
| 49. |
Two charges -q each are fixed separated by distance 2d. A third charge q of mass m placed at the midpoint is displaced slightly by x( x |
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Answer» displacement HORIZONTALLY: If the charge q is displaced slightly to the right side along the line joining the two CHARGES -q, then the force of attraction of the right side -q is more than the force of attraction of the -q on the left side. So +q moves towards right side. As it moves closer to the -q (right side), the force increases. Then it will ACCELERATE more and collide with it.================case 2) displacement of +q along the perpendicular bisector of line joining two charges -q and -q.Let the direction of x be towards the TOP upwards from the center. Let the origin be at the center of two charges -q. Let the charge q be displaced by x , where x << d. The distance between the two charges is 2 d. Mass of charge q is m. The distance between -q and +q = √(d² + x²)Let K = 1/[ 4 πε ].see the diagram. Let F1 be the force due to -q on the right and F2 be the force due to -q on the left side. They are equal in magnitude and directions are as shown. magnitude = F1 = F2 = K q² / (d² + x²) Components of F1 and F2 along the perpendicular bisector are: F1 Sin Ф = K q² x / (x²+d²)³/² The components of these forces parallel to the line joining -q charges are = F1 Cos Ф and will cancel as they are in OPPOSITE directions.Let F and a be the instantaneous resultant force and net acceleration of +q. Then the resultant force on q due to the two charges: F = 2 K q² x / (d²+x²)³/² towards the origin in the direction of - x. m d² x/ dt² = - 2 K q² x / [d³ (1 + x²/d²)³/² ] = - 2 K q² x / d³ if x << d, then we ignore x² as it is << d² m d² x / d t² = - [ 2 q² / 4 π ε d³ ] x = ⁻ω² x This is the equation of motion of the charge q. SO q oscillates in a simple harmonic motion with an amplitude of x₀ that is the displacement at t = 0. The angular frequency of oscillation = ω = q / √ (2π ε d³) |
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If water is an insulator, then why do we get an electric shock when we touch the electric circuit with wet hands? |
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Answer» in WATER there is some palticles of SALT and salt is PASS ELECTRICITY so water is ALSO pass electricity from it. |
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