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This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 15051. |
A liquid is filled into a semielliptical cross - section with a as semi major axis and b as semi minor axis. The ratio of the surface tension forces on the curved part and the plane part of the tube in vertical position will be |
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Answer» `(PI(a+B))/(4B)` |
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| 15052. |
A body of mass 15g oscillates about a fixed point with a SHM of amplitude 8cm. If the body is attracted towards the fixed point, when at a distance of 4 cm from it with a force equal to the weight of 10g, the period of oscillation of the mass about the fixed point is |
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Answer» 0.2916sec |
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| 15053. |
In an empty room why is it that a tone sounds louder than in the room having things like furniture etc. |
| Answer» Solution :Because in a FURNITURE ROOM will absorb the SOUND waves, hence there went be any echo. But in an empty room reflect the sound. Therefore there will be echo hence we hear sound louder. | |
| 15054. |
The focal lengths of a lens are in the ratio 8:3 when it is immersed in two different liquids of refractive indices 1.6 and 1.2 respectively. The refractive index of the material of the lens is |
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Answer» `1.25` |
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| 15055. |
(A) : A rectangular lamina has least moment of inertia about an axis passing through centre and lying in its plane with axis parallel to largest dimension. (R ) : Any rigid body has minimum moment of Inertia about an axis passing through centre of gravity wrt any parallel axis. |
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Answer» Both (A) and (R ) are TRUE and (R ) is the CORRECT explanation of (A) |
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| 15056. |
Sand drops from a stationary hopper at the rate of 5 kgs^(-1) onto a conveyor belt moving with a constant speed of 2ms^(-1). What is the force required to keep the belt moving and what is the power delivered by the motor moving the belt ? |
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Answer» Solution :IMPULSE j = FT = mv, `F = (mv)/(t)` `v=2ms^(-1),(m)/(t)=5KGS^(-1)rArrF=10N` power `P=(W)/(t)=(Fs)/(t)=Fv` `=10xx2=20` walt. |
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| 15057. |
A vehicle moving with a speed of 18 kmh^(-1) covers……….m in 1 s. |
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Answer» Solution :Speed `V=(KM)/(h)` `v=(18xx1000)/(3600)` 1 km =100 m , 1 hr =3600 s)` `v=5 (m)/(s)` DISTANCE x=vt `x=5(1) ( :. t=1s)` `x=5m` |
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| 15059. |
A proejectile fired with velocity u at right angle to the slope which is inclined at an angle theta with horizontal. The expression for R is |
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Answer» `(2U^(2))/(g) tan theta` |
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| 15060. |
A rectangular block has a square base measuring a xx a, and its height is h, It moves with a speed v on a smooth horizontal surface |
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Answer» It will TOPPLE if `V gt SQRT(2gh)`. |
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| 15061. |
A rocket has a mass of 21000 kg of which is fuel. The rocket engine can exhaust fuel at the rate of 190 kg s^(-1) withan exhaust velocity 2500 ms^(-1) relative to the rocket. If the rocket is fired vertically upwards, its final velocity at the burn out is (in ms^(-1)) [given ln (3.5) = 1.253] |
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Answer» 2735 |
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| 15062. |
The mass of a ball is four times the mass of another ball. When these balls are separated by a distance of 10 cm, the gravitational force between them is 6.67 xx 10^(-7) N . Find the masses of the two balls. |
| Answer» SOLUTION :`m_1 =5KG, m_2 = 20KG ` | |
| 15063. |
When the capillary tube is lowered into water, the mass of water raised in the tube, above the outside water level is 5gm. If the radius of the tube is doubled, the mass of water that rises in the capillary tube above the outside water level is |
| Answer» ANSWER :C | |
| 15064. |
A particle executes shm in a line 10 cm long. When it passes through the mean position its velocity is 15 cms^(-1) .Find the period. |
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| 15065. |
Image distance |v| vs object distance |u| curve for two biconvex lenses with same radii of curvatures is shown in the figure. If refractive index of lens 1 is 5/2, then refractive index of lens 2 is 0.5 x. find value of x. |
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| 15066. |
Four point masses, each of value m, are placed at the corners of a square ABCD of side 1. The moment of inertia of this system about an axis through A and parallel to BD is |
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Answer» `ml^2` `THEREFORE AO xx (1)/(sqrt2)= (l)/(2)` or `AO = (l)/(sqrt2)` `I = I_(D) + I_(B) + I_(C)` or `I = (2ml^2)/(2) + m ((2L)/(sqrt2))^(2)` = `(2ml^(2))/(2) + (4ml^2)/(2)` or `I = (6ml^2)/(2) = 3ml^2` 
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| 15067. |
If man were standing unsymmetrically between parallel cliffs, claps his hands and starts hearing a series of echoes at intervals of 1 s. If speed of sound in air is 340 ms-1, the distance between two cliffs would be ...... |
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Answer» (A) 340 m  Here distance between two CLIFFS is supppose d which is equal to x + y. Suppose `x lt y` Here when sound is produced from position S at time `t =0,` first echo is heard at time `t_(1) -0= t _(1)=1s` (as per statement) as SECONS echo is heard at time `t _(2) -0 =t _(2) =t _(1) +1 (because` successive echose are heard at an INTERVAL of 1 s and so ` t _(2) -t_(1) = 1s)` Now, `2x =vt _(2)` `2y = vt _(2)` `therefore 2x + 2y =v (t _(1) + t _(2))` `therefore 2 (c + y ) = v (t _(1) + y _(2))` `therefore 2d = v (t _(1) + t _(2))` `therefore d = (v (t _(1) + t _(2)))/( 2) = (340 (1+2))/( 2) = 510 m` |
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| 15068. |
Coefficient of restitution depends upon |
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Answer» the relative VELOCITIES of approach and separation |
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| 15069. |
When the water tap is closed with our fingers jets of water gush through the space between fingers with high speed. Why? |
| Answer» Solution :AV = a CONSTANT , when a is decreased v is increased | |
| 15070. |
Water rises in a capillary tube to a height of 2.0 cm. In another capillary tube whose radiuus is one third of it, how much the water will rise? |
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Answer» Solution :From equation , we have `H prop 1/r implies hr = "constant"` CONSIDER two capillary TUBES with RADIUS `r_1 and r_2` which on placing in a liquid, capillary rises to height `h_1 and h_2`, respectively, Then , `h_1 r_1 = h_2r_2` = constant `implies h_2 = (h_1r_1)/(r_2) = ((2 xx 10^(-2) m)xxr)/(r ) implies h_2 = 6 xx 10^(-2) m`. |
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| 15071. |
Highway police detect over speeding vehicles by using |
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Answer» MAGNUS effect |
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| 15072. |
Explain with illustration cranes regarding the applications of elastic behaviour of materials. |
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Answer» Solution :For in all ENGINEERING designs, elastic behaviour of materials play important role. Let us consider the illustration of cranes for this. Cranes used for lifting and moving heavy loads from one place to another have a thick metal rope to which the load is attached and so rope (Cable) is under stress. Suppose we want to make a crane, which has a lifting capacity of 10 tonnes or metric TONS (1 metric ton = 1000 kg). How thick should the STEEL rope be ? For that load does not deform the rope permanently. Therefore, the extension should not exceed the elastic limit. Means the value of yield strength S, produced in rope is less than the value of elastic limit. Suppose the least cross sectional area of rope of mild steel is A and yield strength of mild steel `(S _(y)) is 300 xx 10 ^(6) Nm ^(-2)` `therefore A ge (W)/( S _(y))` `= (MG )/( S _(y))` `= (10 ^(4) kg xx 10 ms ^(-2))/( 300 xx 10 ^(6) Mm ^(-2))` `= 3.3 xx 10 ^(-4) m ^(2)` `therefore A ge 3.3 xx 10 ^(-4) m ^(2)` IF ` g = 3.1 pi ms ^(-2) and A = pi R ^(2) ` then, From `A = (Mg )/(S _(y)) [ becauseg = 9.8 =3.1 xx pi ms ^(-2)]` br> `pi r ^(2) = ( 10 ^(4) xx 3.1xx pi)/( 300 xx 10^(6)) ` `therefore r ^(2) = (3.1)/(3) xx 10 ^(-4)` `therefore r ^(2) = 1. 033 xx 10 ^(-4)` `therefore r = 1.06 xx 10 ^(-2) m` `therefore r ~~ 1cm` Generally a large margin of safety (of about a factor of ten in the load) is provided. Thus, a thickeer rope of radius about 3 cm recommended. A single wire of readius of 3 cm would be a rigid rod. So the ropes are always made of a number of thin wires BRAIDED together. |
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| 15073. |
Time taken by light to cross a distance of nuclear size is of the order of………. . |
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| 15074. |
A thermodynamic system is taken from an initial state I with internal energy U_(i)=100 J to the final state f along two different paths iaf and ibf, as schematicallly shown in the figure. The work donw by the system along the paths af, ib and bf are W_(af)=200 J,W_(ib)=50J and W_(bf)=100 J respectively.the heat supplied to the system along the path iaf, ib and bf are Q_(iaf)Q_((jb) and Q_(bf) repsectively.If the internal energy of the system in the state b is U_(b) =200 J and Q_(iaf) =500J, the ratio Q_(bf)//Q_(jb)is In the figure a container is shown to have a movable(without friction) piston on top. The container and the piston are all made of perfectly insualting material allowing no heat transfer between outside and inside the container The container is divided int to two compartments by a rigid partition made of a themally conducting material that allows slow tranfer of heat.The lower compartment of the container is filled with 2 moles of an ideal monatiomic gas at 700 K and the upper compartment is filled with 2 moles of an ideal diatomic gas at 400 K.The heat capacitites per mole of na ideal monatomic gas are C_(v)=(3)/(2)R,C_(p)=(5)/(2)r, and those for an ideal diatomic gas are C_(v)=(5)/(2)r,c_(p)=(7)/(2)R. |
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| 15075. |
Asystem goes from P to Q by two different paths in the P -V diagram as shown in figure. Heat given to the system in path 1 is 1000 J. The work done by the system along path 1 is more than path 2 by 100 J. What is the heat exchanged by the system in path 2 ? |
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Answer» SOLUTION :For path 1: Heat GIVEN `Q_1`=+1000 J Work done = `W_1` For path 2: Work done `W_2=W_1-100J` Heat given `Q_2`= ? As CHANGE in internal energy between TWO states for different path is same. `therefore DeltaU=Q_1-W_1=Q_2-W_2` `therefore 1000-W_1=Q_2-(W_1-100)` `therefore Q_2=1000-W_1+W_1-100` `therefore Q_2`=900 J |
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| 15076. |
Portion AB of the wedge shown in figure is rough and Bc is smooth. A solid cylinder rolls without spinning from A to B. If AB=BC, then ratio of transitional kinetic energy to rotational kinetic energy, when the cylinder reaches point C is |
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Answer» `3/5` |
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| 15077. |
Length cannot be measured by |
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Answer» fermi |
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| 15078. |
A vertical cylinder of height 100cm contains air at a constant temperature and its top is closed by a frictionless pistion at atmospheric pressure (76cm of Hg) as shown figure (a). If mercury is slowly poured on the pistion, due to its weight air is compressed. Find the maximum height of the mercury column which can be put on the pistion. |
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Answer» 12 cm |
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| 15079. |
The velocity of a particle when at its greatest height is sqrt((2)/(5)) of its velocity when at half of its greatest height find the angle of projection |
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Answer» Solution :Step - 1: we know that, velocity of a projectile at half of maximum height `= usqrt((1+ cos^(2) THETA)/(2))` Step 2 : given that `u cos theta = sqrt((2)/(5)) XX u sqrt((1+cos^(2) theta)/(2))` SQUARING on both sides `u^(2) cos^(2) theta = (2)/(5) u^(2) ((1+cos^(2) theta)/(2))` `10 cos^(2) theta = 2+ 2 cos^(2) theta` `RARR 8 cos^(2) theta = 2 rArr cos^(2) theta = (1)/(1) rArr theta = 60^(@)` |
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| 15080. |
A water tank which is on ground has an arrangement to maintain a constant water level of depth 60 cm. Through a hole on its vertical wall at a depth of 20cm from the free surface water comes out and reaches the ground at a certain distance. To have the same horizontal range another hole can be made at a depth of |
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Answer» 30 cm |
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| 15081. |
The temperature inside a refrigerator is t_(2)^(@)C and the room temperature is t_(1).^(@)C. The amount of heat delivered to the room for each joule of electrical energy consumed ideally will be |
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Answer» `(t_(1))/(t_(1) - t_(2))` For refrigerator, `("Heat given to high temperature "(Q_(1)))/("Heat taken from lower temperature "(Q_(2))) = (T_(1))/(T_(2))` `(Q_(1))/(Q_(2)) = (t_(1) + 273)/(t_(2) + 273)` `rArr (Q_(1))/(Q_(1) - W) = (t_(1) + 273)/(t_(2) + 273)` or `1 - (W)/(Q_(1)) = (t_(2) + 273)/(t_(1) + 273)` or `(W)/(Q_(1)) = (t_(1) - t_(2))/(t_(1) + 273)` The amount of heat delivered to the room for each JOULE electric ENERGY (W= 1J) `Q_(1) = (t_(1) + 273)/(t_(1) - t_(2))` |
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| 15082. |
Which substances are called elastomers? Given one example. |
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Answer» Solution :Elastomers are those materials for which stress- strain variation is not a STRAIGHT line within ELASTIC LIMIT. An elastomer is a POLYMER with viscoelasticity (colloquially elasticity), generally having low young.s modulus and HIGH faillure strain compared with other material. Example- Rubber. |
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| 15083. |
At the surface of earth, the acceleration due to gravity is g. If an object of mass m is raised from the surface of earth to a height equal to radius of earth (R ). The potential energy gained by the object is |
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Answer» mgR `U_(2) = -(GMm)/(R )` At a height R from surface of earth, the gravitational potential energy `U_(2) = -(GMm)/((R+R)) = - (GMm)/(2R)` `Delta U = U_(2) - U_(1) = -(GMm)/(2R) - (-(GMm)/(R ))` `= (GMm)/(2R)` `= (gR^(2)m)/(2R) ""(because G = (GM)/(R^(2)),(gR^(2) = GM))` Therefore, `U_(2) - U_(1) = (MgR)/(2)` |
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| 15084. |
Two lead bullets of equal mass top after head-on Collison and reach their melting point due to the heat generated. The temperature of the bullets before collision was 35^(@)C. Find the relative velocity of the bullets before collision. Specific heat of lead = 0.03 cal cdot g^(-1)cdot^(@)C^(-1), melting point of lead = 335^(@)C, J = 4.18 xx 10^(7) erg cdot cal^(-1). |
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| 15085. |
The coefficient of apparent expansion of a liquid at two different temperatures, match the Column- I with Column- II. gamma_( "app") = (m_1- m_2)/(m_2( Delta theta ) ) , gamma_( "app")(m_1 - m_3)/( m_3 ( Delta theta ) ) {:("Column-I","Column-II"),("A)" m_(2) = (m_1)/( 3) , m_(3) = (m_1)/( 2),"P)" ( Delta theta ) /( Delta theta') = (7)/( 5)),("B)" m_(2) = (m_1)/( 4) ","m_(3) = (m_1)/( 3) ,"Q)" (Delta theta )/(Delta theta ') = (6)/(1)),("C)" m_(2) = (M_1)/( 4)","m_(3) = (2m_1)/( 3) ,"R)" (Delta theta )/( Delta theta') = (3)/(2)),("D)" m_(2) = (m_1)/( 8)"," m_(3) = (m_1)/( 6) , "S)" (Delta theta )/( Delta theta ') = (2)/(1)):} |
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| 15086. |
Which of the following statements is not correct regarding conservation laws? |
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Answer» A CONSERVATION law is a hypothesis based on observations and experiments |
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| 15087. |
An aeroplane flies along a straight line from A to B with a speed v_(0) and back again with the same speed v_(0). A steady wind v is blowing. If AB = 1 then a)total time for the trips is (2v_(0)l)/(v_(0)^(2) - v^(2)) if wind blows along the line AB b) total time for tips is (2l)/(sqrt(v_(0)^(2) - v^(2)), if wind blows perpendicular to the line AB c) total time for the trip decreases because of the presece of wind d) total time for the trip increases because of the presence of wind |
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Answer» a, B, d are CORRECT |
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| 15088. |
A swimmer's speed in the direction of flow of river is 16 km h^(- 1).Against the direction of flow of river, the swimmer's speed is 8 km h^(-1). The swimmer's speed in still water and the velocity of flow of the river respectively are |
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Answer» `12KM h^(-1) , 4km h^(-1)` By solving, we get the speed of swimmer in STILL water, u ` = 12km h^(-1)` Speed of flow of river ` v = 4kmh^(-1)` |
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| 15089. |
A copper block of mass 2.5 kg is heated in a furnace to a temperature of 500^(@)C and then placed on a large ice block. What is the maximum amount of ice that can melt ? (Specific heat of copper =0.39" Jg"^(-1)K"^(-1), heat of fusion of water =335" Jg"^(-1)). |
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Answer» Solution :HEAT obtained by copper block from furnace, `Q=m_(1)CDeltatheta`. . . (1) When heated block is placed on large ice block then `m_(2)` mass of ice starts melting. Required meat for melting, `Q.=m_(2)L.` . . .(2) But `Q=Q.` `:.m_(1)C DELTA theta=m_(2)L.` `:.m_(2)=(m_(1)C Delta theta)/(L.)` `=(2.5xx0.31xx500)/(335)` `=1.455` `~~1.46` `~~1.5` KG |
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| 15090. |
The Young's modulus of brass and steel are 10 ^(11) Nm ^(-2) and 2 xx 10 ^(11) Nm ^(-2)respectively. A brass wire and a steel wire of the same length extend by 1 mm, each under the same force. If radii of brass and steel wires are R_(B) and R_(S) respectively, then .. . |
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Answer» `R _(S) = (R _(B))/(sqrt2)` `Y= ( F //A)/(DELTA L //L)` `therefore Y = (FL)/(A Delta L) = (FL )/(PI R ^(2) Delta L )` `therefore Y prop (1)/(R ^(2)) [because F,L, Delta L and pi` are constant] `therefore (Y_(S))/( Y_(B)) = ((R_(B))/(R _(S))) ^(2)` `therefore (2 xx 10 ^(11))/( 10 ^(11)) = ((R _(B))/( R _(S))) ^(2)` `therefore 2 = ((R _(B))/( R _(S)))^(2)` `therefore sqrt2 = (R _(B))/( R _(S))` `therefore R _(S) = (R _(B))/(sqrt2)` |
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| 15091. |
While jumping out of a moving bus, what must be done for a safe jump? |
| Answer» Solution :A passenger of the BUS WOULD jump out running in the DIRECTION of motion of the bus because the body of the passenger TENDS to MOVE forward by inertia of motion. | |
| 15092. |
An audio oscillator capable of producing notes of frequencies ranging from 500 Hz "to" 1500 Hz is placed constant tension T. The linear mass density of the wire is 0.75 g//m. It is observed that by varying the frequency of the oscillator over the given permissible rang the sonometer wire sets into vibration at frequencies 840 Hz and 1120 Hz. a. Find the tension in the string . b. What are the frequencies of the first and fourth overtone produced by the vibrating string? |
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Answer» In the frequency of the fundamental note `= f_(0)` `:. F_(0) = (1)/( 2l) sqrt((T)/( mu))` where `f_(0) = (840)/(3) = 280 HZ` or `T = 4 l^(2) mu f_(0)^(2) = 4 (0.25)^(2) xx (0.75 xx 10^(-3)) xx (280)^(2)` ` = 14.7 N` b. Frequency of the FIRST overtone ` = 2 f_(0) = 2 xx 280 = 560 Hz` and that of fourth overtone ` = 5 f_(0) = 5 xx 280 = 140 Hz` |
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| 15093. |
A variable force, given by the 2-dimensional vector vec(F)=(3x^(2)hat(i)+4hat(j)), acts on particle. The force is in newton and x is in metre. What isd the change in the kinetic energy of the particle as it moves from the point with coordinates (2,3) to (3,0) ? (The coordinates are in metres) |
| Answer» Answer :C | |
| 15094. |
So as to observe the nature of the gas, the student performs measurement s with thermometers having different gases. The student finds that |
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Answer» Measurements are almost independent of the nature of the GAS, if the gas pressure is low and the TEMPERATURE is well above the temperature at which the gas liquefies. |
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| 15095. |
P is a fixed smooth cylinder of radius R and Q is a disc of mass M and radius R. A light thread is tightly wound on Q and its end is connected to a rope ABC. The rope has a mass m and length (piR)/(2)and is initially placed on the cylinder withits end A at the top. The system is released from rest. The rope slides down the cylinder as the disc rolls without slipping. The initial separationbetween the disc and the cylinder was L = (piR)/(2)(see fig). Find the speed with which the disc will hit the cylinder. Assume that the rope either remains on the cylinder or remains vertical, itdoes not fly off the cylinder. |
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| 15096. |
A U-tube is supported with its limbs vertical andis partly filled with water. If internal diameters of the limbs are 1xx10^(-2)m and 1xx10^(-4)m respectively, wht will be the difference in heights of water columns in the two limbs (Surface tension of water is 0.07 Nm^(-1)) |
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Answer» Solution :Surface tension, `S=0.07Nm^(-1)` Density, `rho=1000k gm^(-3),g=9.8ms^(-2)` ANGLE of CONTACT `theta=0^(@)`, RADIUS, `r_(1)=0.5xx10^(-2)m`, Radius, `r_(2)=0.5xx10^(-4)m` Let `h_(1)` be the height of water in the limb of radius `r_(1)`. Then, `h_(1)=(2Scostheta)/(r_(1)rhog)=(2xx0.07xxcos0^(@))/(0.5xx10^(-2)xx1000xx9.8)m` `=2.86xx10^(-3)m` similarly `h_(2)=2.86xx10^(-1)m`. Difference in HEIGHTS `=h_(2)-h_(1)=2.86xx10^(-1)m-2.86xx10^(-3)m` `=(0.286-0.00286)m=0.283m` |
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| 15097. |
Derive the expression for resultant spring constant when two springs having constant k_(1) and k_(2) are connected in parallel. |
Answer» Solution :`k_(1) and k_(2)` attached to a mass m as SHOWN in figure. The results can be generalized to any number of springs in parallel.  Let the force F be applied towards right as shown in figure. In this case, both the springs elongate or compress by the same amount of displacement. Therefore, net force for the displacement of massm is `F=-k_(P),x""...(1)` where `k_(P)` is called effective spring constant. Let the first spring be elongated by a displacement x due to force `F_(1)` and second spring be elongated by the same displacement x due to force `F_(2)`, then the net force `F=-k_(1)x-k_(2)x""...(2)` EQUATING equations (2) and (1), we get `k_(P)=k_(1)+k_(2)""...(3)` Generalizing, for n springs connected in parallel, `k_(P)=UNDERSET(i=1)overset(n)Sigmak_(i)""...(4)` If all spring constants are identical i.e., `k_(1)=k_(2)=...=k_(n)=k` then `k_(P)=NK""...(5)` This IMPLIES that the effective spring constant increases by a factor n. Hence, for the springs in paralle connection, the effective spring constant is greater than individual spring constant. |
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| 15098. |
A car is moving with a speed of 30 ms^(-1)on a circular path of radius 500 m. If its speed is increasing at the rate of 2 ms^(-2) , the net acceleration of the car is |
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Answer» `3.6 MS^(-2)` |
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| 15099. |
Derive the expression for resultant spring constant when two springs having constant k_(1) and k_(2) are connected in series. |
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Answer» Solution :LET `x_(1) and x_(2)` be the elongation of springs from their equilibrium position (un-stretched position) due to the applied force F. Then, the net displacement of the mass POINT is `X=x_(1)+x_(2)""...(1)` From Hooke.s law, the net force `F=-k_(s)(x_(1)+x_(2))impliesx_(1)+x_(2)=-(F)/(k_(s))""...(2)`  For springs in series connection `-k_(1)x_(1)=-k_(2)x_(2)=F` `implies x_(1)=-(F)/(k_(1))andx_(2)=-(F)/(k_(2))""...(3)` Therefore, substituting EQUATION (3) in equation (2), the effective spring constant can be calculated as `-(F)/(k_(1))-(F)/(k_(2))=-(F)/(k_(s))` `(1)/(k_(s))=(1)/(k_(1))+(1)/(k_(2))" (or) "k_(s)=(k_(1)k_(2))/(k_(1)+k_(2))Nm^(-1)""...(4)` Suppose we have n springs connected in series, the effective spring constant in series is `(1)/(k_(s))=(1)/(k_(1))+(1)/(k_(2))+(1)/(k_(3))+...+(1)/(k_(n))=underset(i=l)overset(n)Sigma(1)/(k_(i))""...(5)` If all spring constants are identical i.e., `k_(1)=k_(2)=...=k_(n)=k` then `(1)/(k_(s))=(n)/(k)impliesk_(s)=(k)/(n)""...(6)` This means that the effective spring constant REDUCES by the factor n. Hence, for springs in series connection, the effective spring constant is lesser than the individual spring constant. From equation (3), we have, `k_(1)x_(1)=k_(2)x_(2)` Then the ratio of compressed distance or elongated distance `x_(1)andx_(2)` is `(x_(2))/(x_(1))=(k_(1))/(k_(2))""...(7)` The elastic potential energy stored in first and second springs are `V_(1)=(1)/(2)k_(1)x_(1)^(2)andV_(2)=(1)/(2)k_(2)x_(2)^(2)` respectively. Then, their ratio is `(V_(1))/(V_(2))=((1)/(2)k_(1)x_(1)^(2))/((1)/(2)k_(2)x_(2)^(2))=(k_(1))/(k_(2))((x_(1))/(x_(2)))^(2)=(k_(2))/(k_(1))""...(8)`
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| 15100. |
The Young's modulus of rubber is |
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Answer» GREATER than that of steel |
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