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InterviewSolution
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.
| 351. |
When a spiral spring is stretched by suspending a load on it, the strain produced is calledA. longitudinalB. shearingC. volumetricD. elastic |
| Answer» Correct Answer - B | |
| 352. |
a long spring is stretched by 4 cm, and its potential energy is 80 J. If the spring is compressed by 2 cm, its potential energy will beA. 320 JB. 20 JC. 120 JD. 60 J |
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Answer» Correct Answer - B `(E_(2))/(E_(1)) =(F_(2))/(F_(1)) xx (l_(2))/(l_(1)) =(yAl_(2))/(yAl_(1)) xx (L)/(L) xx (l_(2))/(l_(1)) =(l_(2)^(2))/(l_(1)^(2))` `therefore E_(2) =(4 xx 80)/(16) = 20J. ` |
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| 353. |
A long elastic spring is stretched by `2 cm` and its potential energy is `U`. If the spring is stretched by `10 cm`, the `PE` will beA. U/25B. 2UC. 5UD. 25U |
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Answer» Correct Answer - D `(u_(2))/(u_(1)) =((1)/(2) kx_(2)^(2))/((1)/(2) kx_(1)^(2)) =((10)/(2))^(2)=25` `u_(2) =25u.` |
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| 354. |
A spray gun is shown in the figure where a piston pushes air out of a nozzle. A thin tube of uniform cross section is connected to the nozzle. The other end of the tube is in a small liquid container. As the piston pushes air through the nozzle, the liquid from the container rises into the nozzle and is sprayed out. For the spray gun shown, the radii of the piston and the nozzle are 20mm and 1mm respectively. The upper end of the container is open to the atmosphere. If the density of air is `rho_a`, and that of the liquid `rho_l`, then for a given piston speed the rate (volume per unit time) at which the liquid is sprayed will be proportional toA. `sqrt((rho_(a))/(rho_(l)))`B. `sqrt(rho_(a)rho_(l))`C. `sqrt((rho_(l))/(rho_(a)))`D. `rhol` |
| Answer» Correct Answer - A | |
| 355. |
A steel rod of length `25cm` has a cross-sectional area of `0.8cm^(2)` . The force required to stretch this rod by the same amount as the expansion produced by heating it through `10^(@)C` is `(alpha_(steel)=10^(-5)//^(@)C` and `Y_(steel)=2xx10^(10)N//m^(2))`A. 40NB. 80NC. 120ND. 160N |
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Answer» Correct Answer - D `F=yA prop Delta T` `=2xx10^(10) xx 0.8 xx 10^(-4) xx 10^(-5) xx 10=160N`. |
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| 356. |
A wire suspended vertically from one end is stretched by attaching a weight of 20 N to the lower end. The weight stretches the wire by 1 mm. How much energy is gained by the wire ?A. 0.01 JB. 0.02 JC. 0.04 JD. 1 J |
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Answer» Correct Answer - A `W=(1)/(2) f xx l=(1)/(2) xx 20 xx 10^(-3)` `=0.01J`. |
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| 357. |
A wire suspended vertically from one of the its ends is stretched by attaching a weight of 200 N to the lower end. The weight stretches the wire by 1 mm. then the elastic energy stored in the wire isA. 0.2 JB. 10 JC. 20 jD. 0.1 J |
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Answer» Correct Answer - d Elastic energy stored in the wire is `U =( 1)/(2) xx` stress `xx` strain `xx` volume `= (1)/(2) xx (F)/(A) xx (Delta l)/(l) xx Al = (1)/(2) F Delta l` or `U = (1)/(2) xx 200 xx 1 xx 10^(-3) = 0.1 J` |
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| 358. |
A steel wire of radius r is stretched without tension along a straight line with its ends fixed at A and B (figure). The wire is pulled into the shape ACB. Assume that d is very small compared to length of the wire. Young’s modulus of steel is Y. (a) What is the tension (T) in the wire? (b) Determine the pulling force F. Is F larger than T? |
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Answer» Correct Answer - (a) `T = Y pi r^(2) (d^(2)//2l^(2))` , (b) `2T (d//l)` where T is given in answer (a). No F is much smaller. |
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| 359. |
There are two thin films A of liquid and B of polythene, identical in size they are being pulled with same maximum weight W. if the breadth of the films is increased from b to 2 b then the corresponding weights will be respectivelyA. W,WB. `(W)/(2),(W)/(2)`C. `(W)/(2),W`D. `W,(W)/(2)` |
| Answer» Correct Answer - D | |
| 360. |
Two wires A and B are of the same material. Their lengths are in the ratio 1 : 2 and the diameter are in the ratio 2 : 1. If they are pulled by the same force, then increase in length will be in the ratioA. `2:1`B. `1:8`C. `1:2`D. `8:1` |
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Answer» Correct Answer - B `Y=(MgL_(1))/(pi r_(1)^(2)l_(1)) and Y=(MgL_(2))/(pi r_(2)^(2)l_(2))` `(MgL_(1))/(pi r_(1)^(2)l_(1))=(MgL_(2))/(pi r_(2)^(2)l_(2))` `therefore (l_(1))/(l_(2)) =(L_(1))/(L_(2)) (r_(2)^(2))/(r_(1)^(2)) =(1)/(2) xx ((1)^(2))/((2)^(2)) =(1)/(8)` |
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| 361. |
Two wires A and B are of the same material. Their lengths are in the ratio 1 : 2 and the diameter are in the ratio 2 : 1. If they are pulled by the same force, then increase in length will be in the ratioA. `2:1`B. `1:4`C. `1:8`D. `8:1` |
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Answer» Correct Answer - C |
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| 362. |
A force of `10^3` newton, stretches the length of a hanging wire by 1 millimetre. The force required to stretch a wire of same material and length but having four times the diameter by 1 millimetre isA. `4 xx 10^(3)N`B. `16 xx 10^(3)N`C. `(1)/(4) xx10^(3)N`D. `(1)/(16)xx10^(3)N` |
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Answer» Correct Answer - B |
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| 363. |
Density of rubber is d. A thick rubber cord of length L and cross-section area. A undergoes elongation under its own weight on suspending it. This elongation is proportional toA. dLB. `Ad//L`C. `Ad//L^(2)`D. `dL^(2)` |
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Answer» Correct Answer - D |
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| 364. |
When a steel wire fixed at one end is pulled by a constant force F at its other end , its length increases by l.Which of the following statements is not correct?A. work done by the external force is FL.B. some heat is produced in the wire in the processC. the elastic potential energy of the wire is `(FL)/(2)`D. the heat produced is equal to the half of the elastic potential energy stored in the wire |
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Answer» Correct Answer - D (d) The heat produced is equal to half of the elastic potential energy stored in the wire. |
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| 365. |
The temperature of a wire of length 1 metre and area of cross-section `1 cm^(2)` is increased from `0^(@)C` to `100^(@)C`. If the rod is not allowed to increased in length, the force required will be `(alpha=10^(-5)//.^(@)C and Y =10^(11) N//m^(2))`A. `10^(3) N`B. `10^(4)` NC. `10^(5) N`D. `10^(9) N` |
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Answer» Correct Answer - B (b) F=Force developed `F=Yaalpha(Deltatheta)` `=10^(11)xx10^(-4)xx10^(-5)xx100=10^(4)N` |
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| 366. |
The elastic potential energy of a stretched wire is given byA. `U=(AL)/(2Y)l^(2)`B. `U=(AY)/(2L)l^(2)`C. `U=(1)/(2)((All)/(Y))l`D. `U=(1)/(2)*(YL)/(2A)*l` |
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Answer» Correct Answer - B (b) Elastic potential energy of a stretched wire is given by `E=(1)/(2)xx "stress" xx "strain" xx "volume" =(1)/(2)xx(F)/(A)xx(l)/(L)xxAL` `=(1)/(2)xxYxx"strain"xx "strain"xxAL=(1)/(2)xxYxx((l)/(L))^(2)xxAL` `therefore E=(Ayl^(2))/(2L)` |
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| 367. |
A uniform cylindrical rod of length L and cross-sectional area by forces as shown in figure. The elongation produced in the rod isA. `(3F L)/(8 AY)`B. `(3FL)/(5AY)`C. `(8FL)/(3AY)`D. `(5FL)/(3AY)` |
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Answer» Correct Answer - C (c) Elongation production if the `(2)/(3)` part of length L of rod is stretched by a force of 3F, is given by `DeltaL_(1)=(F_(1)L_(1))/(AY)=(3Fxx(2)/(3)L)/(AY)=2(FL)/(AY)` Total elongation produced in the rod is `DeltaL=DeltaL_(1)+DeltaL_(2)=2(FL)/(AY)+(2)/(3)(FL)/(AY)` `therefore DeltaL=(8)/(3)(FL)/(AY)` |
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| 368. |
The bulk modulus for an incompresssible liquid isA. zeroB. unityC. infinityD. between 0 and 1 |
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Answer» Correct Answer - C `B = -(Deltap)/(DeltaV//V)` `DeltaV = O` for an incompressible liquid. `:. B =oo` |
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| 369. |
The bulk modulus for an incompresssible liquid isA. ZeroB. unityC. InfinityD. Between 0 to 1 |
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Answer» Correct Answer - C |
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| 370. |
A body of mass `M` is attached to the lower end of a metal wire, whose upper end is fixed . The elongation of the wire is `l`.A. Loss in gravitational potential energy of` M` is `Mgl`B. The elastic potential energy stored in the wire is ` Mgl`C. The elastic potential energy stored in the wire is `1/2 Mgl`D. Heat produced is `1/2 Mgl` |
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Answer» Correct Answer - A::C::D Half of energy is lost in heat and rest half is stored as elastic potential energy . ` l = (Mgl)/(AY)` …(i) ` U = 1/2 Kl^(2) = 1/2((YA)/(L))l^(2)` …(ii) From Eqs. (i) and (ii) , we can prove that `U = 1/2 Mgl` |
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| 371. |
Which one of the following substances possesses the highest elasticity-A. rubberB. glassC. steelD. copper |
| Answer» Correct Answer - C | |
| 372. |
Statement-1: Elasticity restoring forces may be conservative. Statement-2: The value of strain for same stress are different while increasing the load and while decreasing the load.A. Statement-1, is true, Statement-2 is true, Statement-2 is correct explanation for statement-1B. Statement-1 is true, statement-2 is true, statement-2 is NOT a correct explantion for statement-1C. statement-1 is true, statement-2 is falseD. statement-1 is false statement-2 is true |
| Answer» Correct Answer - B | |
| 373. |
Assertion : Strain is a unitless quantity. Reason : Strain is equivalent to forceA. If both assertion and reason are true and the reason is the correct explanation of the assertion.B. If both assertion and reason are true but reason is not the correct explanation of the assertion.C. If assertion is true but reason is fa lse.D. If the assertion and reason both are false. |
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Answer» Correct Answer - C |
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| 374. |
Which of the following relations is trueA. `3Y=K(1-sigma)`B. `K=(9 eta Y)/(Y + eta)`C. `sigma=(6K+eta)Y`D. `sigma = (0.5 Y-eta)/(eta)` |
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Answer» Correct Answer - D |
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| 375. |
Depth of sea is maximum at Mariana Trench in West Pacific Ocean. Trench has a maximum depth of about `11km`. At bottom of trench water column above it exerts `1000 atm `pressure. Percentage change in density of sea water at such depth will be around (Given , B `= 2xx10^(9) Nm^(-2) and P_(atm) = 1xx10^(5 Nm^(-2)))`A. about `5%`B. about `10%`C. about `3 %`D. about `7 %` |
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Answer» Correct Answer - A Change in volume , `DeltaV = (-Delta_(p).V_(i))/B` Hence , density at depth of about `11 km ` is `= (Mass)/(Volume) = (rho_(o)xxV_(i))/(V_(i)-(Deltapv_(i))/B) = (rho_(o)B)/((B-Delta_(p)))` `=(rho_(o))/(1-Delta_(p)/B) = (rho_(o))/(1-(1xx10^(8))/(2xx10^(9)` `(rho_(o))/(1-(1)/(20))` = `= (rho)/(0.95) rArr rho = rho_(o)/0.95` ` rArr rho_(o) =0.95rho` `:.` % change in density `= (rho-rho_(o))/rho_(o)xx100` `= [(1/0.95-1)/1]xx100` ` ~~ 5%` |
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| 376. |
One end of a horizontal thick copper wire of length `2L` and radius `2R` is weded to an end of another horizontal thin copper wire of length `L` and radius `R` .When the arrangement is stretched by applying forces at two ends , the ratio of the elongation in the thin wire to that in the thick wire isA. `0.25`B. `0.50`C. `2.00`D. `4.00` |
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Answer» Correct Answer - C ` Deltal = (FL)/((pir^(2))Y)` `:. Deltal prop (L)/(r^(2)) ` `:. (Deltal_(1))/(Deltal_(2))=(L//R^(2))/(2L//(2R)^(2)) =2` |
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| 377. |
Assertion : Spring balances show correct readings even after they had been used for a long time interval. Reason : On using for long time, spring balances losses its elastic strength.A. If both assertion and reason are true and the reason is the correct explanation of the assertion.B. If both assertion and reason are true but reason is not the correct explanation of the assertion.C. If assertion is true but reason is fa lse.D. If assertion is false but reason is true |
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Answer» Correct Answer - D |
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| 378. |
If the interatomic spacing in a steel wire is `3.0 Å and Y_(steel)=20xx10^(10)N//m^(2)` then force constant isA. `6xx10^(-2)N//Å`B. `6xx10^(-9)N//Å`C. `4xx10^(-5)N//Å`D. `6xx10^(-5)N//Å` |
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Answer» Correct Answer - B |
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| 379. |
In the above graph, point B indicates.A. Breaking pointB. Limiting pointC. Yield pointD. None of the above |
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Answer» Correct Answer - C |
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| 380. |
In the above graph, point `D` indicatesA. Limiting pointB. Yield pointC. Breaking pointD. None of the above |
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Answer» Correct Answer - C |
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| 381. |
When a jet of liquid strikes a fixed or moving surface, it exerts thrust on it due to rate of change of momentum. `F=(rhoAV_(0))V_(0)-(rhoAV_(0))V_(0)costheta=rhoAV_(0)^(2)[1-costheta]` If surface is free and starts moving due to thrust of the liquid, then at any instant, the above equation gets modified based on relative change of momentum with respect to surface. Let, at any instant, the velocity of surface be `u`. Then the above equation becomes ` F=rhoA(V_(0)-u)^(2)[1-costheta]` Based on the above concept, as shown in the following figure, if the cart is frictionless and free to move in the horizontal direction, then answer the following. Given that cross sectional area of jet `=2xx10^(-4)m^(2)` velocity of jet `V_(0)=10m//s` density of liquid `=1000kg//m^(3)` ,mass of cart `M=10 kg`. Velocity of cart at `t = 10 s` is equal toA. 4m/sB. 6m/sC. 8m/sD. 5m/s |
| Answer» Correct Answer - C | |
| 382. |
When a jet of liquid strikes a fixed or moving surface, it exerts thrust on it due to rate of change of momentum. `F=(rhoAV_(0))V_(0)-(rhoAV_(0))V_(0)costheta=rhoAV_(0)^(2)[1-costheta]` If surface is free and starts moving due to thrust of the liquid, then at any instant, the above equation gets modified based on relative change of momentum with respect to surface. Let, at any instant, the velocity of surface be `u`. Then the above equation becomes ` F=rhoA(V_(0)-u)^(2)[1-costheta]` Based on the above concept, as shown in the following figure, if the cart is frictionless and free to move in the horizontal direction, then answer the following. Given that cross sectional area of jet `=2xx10^(-4)m^(2)` velocity of jet `V_(0)=10m//s` density of liquid `=1000kg//m^(3)` ,mass of cart `M=10 kg`. Velocity of cart at `t = 10 s` is equal toA. `1.6m//s^(2)`B. `1m//s^(2)`C. `0.64m//s^(2)`D. `0.16m//s^(2)` |
| Answer» Correct Answer - D | |
| 383. |
When a jet of liquid strikes a fixed or moving surface, it exerts thrust on it due to rate of change of momentum. `F=(rhoAV_(0))V_(0)-(rhoAV_(0))V_(0)costheta=rhoAV_(0)^(2)[1-costheta]` If surface is free and starts moving due to thrust of the liquid, then at any instant, the above equation gets modified based on relative change of momentum with respect to surface. Let, at any instant, the velocity of surface be `u`. Then the above equation becomes ` F=rhoA(V_(0)-u)^(2)[1-costheta]` Based on the above concept, as shown in the following figure, if the cart is frictionless and free to move in the horizontal direction, then answer the following. Given that cross sectional area of jet `=2xx10^(-4)m^(2)` velocity of jet `V_(0)=10m//s` density of liquid `=1000kg//m^(3)` ,mass of cart `M=10 kg`. The time at which velocity of cart becomes `2 m/s` is equal toA. 1.6sB. 2sC. 3.2sD. 4s |
| Answer» Correct Answer - A | |
| 384. |
When a jet of liquid strikes a fixed or moving surface, it exerts thrust on it due to rate of change of momentum. `F=(rhoAV_(0))V_(0)-(rhoAV_(0))V_(0)costheta=rhoAV_(0)^(2)[1-costheta]` If surface is free and starts moving due to thrust of the liquid, then at any instant, the above equation gets modified based on relative change of momentum with respect to surface. Let, at any instant, the velocity of surface be `u`. Then the above equation becomes ` F=rhoA(V_(0)-u)^(2)[1-costheta]` Based on the above concept, as shown in the following figure, if the cart is frictionless and free to move in the horizontal direction, then answer the following. Given that cross sectional area of jet `=2xx10^(-4)m^(2)` velocity of jet `V_(0)=10m//s` density of liquid `=1000kg//m^(3)` ,mass of cart `M=10 kg`. The power supplied to the cart when its velocity becomes `5 m//s` is equal toA. 100 WB. 25 WC. 50 WD. 200 W |
| Answer» Correct Answer - C | |
| 385. |
In a U-tube if different liquids are filled then we can say that pressure at same level of same liquid is same. Q. In a U-tube 20 cm of a liquid of density `rho` is on left hand side and 10 cm of another liquid of density 1.5 `rho` is on right hand side in between them there is a third liquid of density `2rho` what is the value of `h`.A. 5 cmB. 2.5 cmC. 2 cmD. 7.5 cm |
| Answer» Correct Answer - B | |
| 386. |
In a U-tube if different liquids are filled then we can say that pressure at same level of same liquid is same. Q. If small but equal lengths of liquid -1 and liquid -2 are increased in their corresponding sides then h willA. remain sameB. increaseC. decreaseD. may increase or decrease. |
| Answer» Correct Answer - C | |
| 387. |
A U-tube of small and uniform cross section contains water of total length 4H the height difference between the water columns on the left and on the right is H when the valve K is closed, the valve is suddenly open, and water is flowing from left to right. ignore friction find the speed of water when the heights of the left and the right water columns are the same.A. `(1)/(4)sqrt(gH)`B. `sqrt((gH)/(8))`C. `(1)/(2)sqrt(gH)`D. `sqrt((gH)/(2))` |
| Answer» Correct Answer - B | |
| 388. |
Water is flowing through a channel that is 12 m wide with a speed of 0.75m/s. the water then flows into four identical channels that have a width of 4.0 m the depth of te water does not change as it flows into the four channels. What is the speed of the water in one of the smaller channels?A. 0.56m/sB. 2.3m/sC. 0.25m/sD. 0.75m/s |
| Answer» Correct Answer - A | |
| 389. |
A unfrom spring whose unstetched length is/ has a force constant K.The spring is interger .What are the force constants `K_(1)andK_(2)` of the two peces in terms of n and K? [Hint :force constant is inversely proportinal tolength.] |
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Answer» Correct Answer - `(n+_1)/(nk)and (n+1)k` |
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| 390. |
There is same change in length when a 33000 N tensile force is applied on a steel rod of area of cross-section `10^(-3)m^(2)` . The change of temperature reuired to produce the same elongation, if the steel rod is heated , if (The modulus of elasticitay is ` 3xx10^(11) N//m^(2)` and the coefficient of linear expansion of steel is ` 11 xx 10^(-5) //^(@)C`).A. `20^(@)`CB. `15^(@)C`C. `10^(@)C`D. `0^(@)C` |
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Answer» Correct Answer - C (c) Modulus of elasticity `=("Froce")/("Area")xx(l)/(Deltal)` `3xx10^(11)=(3000)/(10^(-3))xx(l)/(Deltal)` `(Deltal)/(l)=(33000)/(10^(-3))xx(1)/(3xx10^(11))=11xx10^(-5)` Change in length, `(Deltal)/(l)=alpha DeltaT` `11xx10^(-5)=1.1xx10^(-5)xxDeltaT` `implies DeltaT=10K` or `10^(@)C` |
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| 391. |
A cubical block of wood of edge 3 cm floats in water. The lower surface of the cube just touches the free end of a vertical spring fixed at the bottom of the pot. Find the maximum weight that can be put on the block without wetting it. Density of wood =`800 kgm^-3` and spring constant of the spring `=50Nm^-1 Take g=10ms^-2`. , |
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Answer» The specific gravity of the block `=0.8` Hence the height inside water `=3cmxx0.8=2.4cm` the height outside water `=3cm-2.4=0.6cm` suppose the maximum weight that can be put without wetting it is W. The block in this case is completely immersed in the water. The volume of the displaced water =volume of the block `=27xx10^(-6)m^(3)` Hence the force buoyancy `=(27xx10^(-6)m^(3))xx(1000kg//m^(3))xx(10m//s^(2))=0.27N` The spring is compressed by 0.6 cm and hence the upward force exerted by the spring `=50N//mxx0.6cm=0.3N` The force of buoyancy and the spring force taken together balance the weight of the block plus the weight W put on the block The weight of the block is `W=(27xx10^(-6)m)xx(800kg//m^(3))xx(10m//s^(2))=0.22N` Thus, `W=0.27N+0.3N-0.22N=0.35N` |
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| 392. |
A drop of water of radius 0.0015 mm is falling in air. If the coefficient of viscosity of air is `1.8xx10^(-8)kgm^(-1)s^(-1)` what will be the terminal velocity of the drop. Density of air can be neglected. |
| Answer» `V_(T)=(2)/(9)(r^(2)(rho-sigma)g)/(eta)=(2xx[(15xx10^(-4))/(1000)]^(2)xx10^(3)xx9.8)/(9xx1.8xx10^(-5))=2.72xx10^(-4)m//s` | |
| 393. |
A wooden cylinder of diameter 4 r, height H and density `rho//3` is kept on a hole of diameter 2 r of a tank, filled with water of density `rho` as shown in the The block in the above question is maintained by external means and the level of liquid is lowered. The height `h_(2)` when this external force reduces to zero is A. `(4h)/(9)`B. `(5h)/(9)`C. remains sameD. `(2h)/(3)` |
| Answer» Correct Answer - A | |
| 394. |
A wooden cylinder of diameter 4 r, height H and density `rho//3` is kept on a hole of diameter 2 r of a tank, filled with water of density `rho` as shown in the If height `h_(2)` of water level is further decreased, thenA. cylinder will not move up and remains at its original positionB. for `h_(2)=h//3` cylinder again starts moving upC. for `h_(2)=h//4` cylinder again starts moving upD. for `h_(2)=h//5` cylinder again starts moving up. |
| Answer» Correct Answer - A | |
| 395. |
A cylinder of height 20m is completely filled with water. The velocity of effux of water `(in ms^(-1))` through a small hole on the side wall of the cylinder near its bottom isA. 10B. 20C. 25.5D. 5 |
| Answer» Correct Answer - B | |
| 396. |
The adjoining diagram shows three soap bubbles, A , B and C prepared by blowing the capillary tube fitted with stop cocks S, `S_(1),S_(2)` and `S_(3)` with stop cock S closed and stop cocks `S_(1),S_(2)` and `S_(3)` opened-A. B will start collapsing with volumes of A and C increasingB. C will start collapsing with volumes of A and B increasingC. C and A will both start collapsing with the volume of B increasingD. volumes of A, B and C will become equal to equilibrium. |
| Answer» Correct Answer - C | |
| 397. |
If two soap bubbles of different radii are connected by a tubeA. air flows from the bigger bubble to the smaller bubble till the sizes becomes equalB. air flows from bigger bubble to the smaller bubble till the sizes are interchanged.C. air flows from the smaller bubble to the bigger bubble.D. there is not flow of air. |
| Answer» Correct Answer - C | |
| 398. |
Two soap bubbles each of radius r are touching each other. The radius of curvature of the common surface will be:A. infiniteB. 2rC. `r`D. `r//2` |
| Answer» Correct Answer - A | |
| 399. |
A container filled with air under pressure `P_(0)` contains a soap bubble of radius `R` the air pressure has been reduced to half isothermally and the new radius of the bubble becomes `(5R)/(4)` if the surface tension of the soap water solution. Is S, `P_(0)` is found to be `(12nS)/(R)`. Find the value of n. |
| Answer» `(P_(0)+(4S)/(R))((4)/(3)piR^(3))=((P_(0))/(2)+(4Sxx4)/(5R))xx(4)/(3)pi((5R)/(4))^(3)impliesP_(0)+(4S)/(R)=((P_(0))/(2)+(16S)/(5R))(125)/(64)impliesP_(0)=(96S)/(R)` | |
| 400. |
A soap bubble in vacuum has a radius of 3 cm ad another soap bubble in vacuum has a radius of 4 cm. if the two bubbles coalesce under isothermal condition, then the radius of the new bubble isA. 2.3 cmB. 4.5 cmC. 5 cmD. 7 cm |
| Answer» Correct Answer - C | |