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classical smog. The smog is formed by condensation of water vapour with H2S and SO2 over dust and smoke particles. It is dark brown and opaque.
Ideal gas equation, PV = nRT n = w/M where w is weight of gas and M is molar mass PV = w/M (RT) => PM = w/V (RT)                    (density, d =w/V) => PM = dRT d = PM/RT d = 5x28/0.082x500 = 3.41 g/ml  
Let Z = x +iy Hence z will lie on imaginary axis for every x  
Alpha emission :  Beta Emission :  In this problem, both alpha and beta emissions are taking place. Putting value of A and Z Now in the product nucleus, Number of protons = 82 and number of neutrons = 206-82 =  124 Ratio of Neutron/Proton = 124/82 = 62/41  
No potential energy is not negative when you displace particle against gravitation.  Take help of vectors for understanding this, Now if you are displacing particle against gravity that means you are taking particle in upward direction while the direction of g is in downward. So the dot product will give positive value equal to mgh.
Vapour pressure of liquid ‘S’ at 500 K is approximately equal to
As we have learnt,   Δ G of equilibrium -   - wherein At Equilibrum     and 
Work done by frictional is zero when the object to which it is acing does not move any distance.

A ray of light is incident on a medium with angle of incidence i and refracted into a second medium with angle of refreaction r. The graph of sin i vs sin r is shown in the figures. Then the velocity of light in the first medium is n times the velocity of light in the second medium. The value of n should be.

As the figure is not mentioned, I would be suggesting a way to solve this problem. Now, Speed of the light in that medium  can be told with the help of the Refractive Index.         Refractive Index = Sini/Sinr where i is the angle of Incidence and r is the angle of the Refraction.  But, Refractive Index = Speed of light in medium 1/Speed of light in medium 2.  ∴ Speed of light in medium...
Dimension of Energy = Dimension of Work W = F.l If units of force and length increases 4 times then, W = 4F.4l = 16F.l  Hence unit of Energy will increase 16 times

Equation of sound wave in air is given by \Delta P = 0.02\sin[300t - (9.0)x]. Find the speed of sound in air.

 

Compare with general equation   Pressure Waves -   - wherein  = Maximum variation in pressure
In an electrical circuit R, L, C and an a.c. voltage source are all connected in series. When L is removed from the circuit, the phase difference between the voltage and the current in the circuit is pi/3 . If instead, C is removed from the circuit, the phase difference is again pi/3 . The power factor of the circuit is:
As we learnt in Impedence - -     Power factor -   - wherein resistance impedence              when C is removed from the Circuit Power factor 
 Potassium permanganate is an inorganic chemical compound with the formula KMnO4. It is a salt consisting of K+ and MnO4 − ions.It known as permanganate of potash, it is a strong oxidizing agent. It dissolves in water to give intensely purple solutions.
the nitration of benezene using mixed conc. H2SO4 and HNO3 If a large amount of KHSO4 is added to the mixture, the rate of nitration will be
Nitrobenzene is formed in the nitration process of benzene using concentrated and . The reaction is given by; If a large amount of  is added to the mixture, more  ion furnishes and rate of electrophilic aromatic reaction slow down i.e concentration of electrophile is decreased. Hence addition of a large amount of   to the mixture tends to slow down the rate of nitration.
Engineering
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 3-Methyl-pent-2-ene on reaction with HBr in presence of peroxide forms an addition product. The number of possible stereoisomers for the product is :

 

  • Option 1)

    Two

  • Option 2)

    Four

  • Option 3)

    Six

  • Option 4)

    Zero

 
The product obtained has 2 stereocent x and molecube is unsymmetrical No of stereoisomers = hence total stereoisomers = 4   Option 1) Two This is incorrect option Option 2) Four This is correct option Option 3) Six This is incorrect option Option 4) Zero This is incorrect option
Engineering
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 pKa of a weak acid (HA) and pKb of a weak base (BOH) are 3.2 and 3.4, respectively. The pH of their salt (AB) solution is :

 

  • Option 1)

    7.0

  • Option 2)

     1.0

     

  • Option 3)

    7.2

     

  • Option 4)

     6.9

     

 
As we learned in We know that =>                = 6.9 Option 1) 7.0 This option is incorrect. Option 2)  1.0   This option is incorrect. Option 3) 7.2   This option is incorrect. Option 4)  6.9   This option is correct.
Engineering
762 Views   |  

A physical quantity P is described by the relation

P= a1/2 b2 c3 d-4

If the relative errors in the measurement of a, b, c and d respectively, are 2%, 1%, 3% and 5%,

then the relative error in P will be :

  • Option 1)

    8%

  • Option 2)

    12%

  • Option 3)

    32%

  • Option 4)

    25%

 
P = a1/2b2C3d-4100() =  =  Option 1) 8% this is incorrect option Option 2) 12% this is incorrect option Option 3) 32% this is correct option Option 4) 25% this is incorrect option
Engineering
100 Views   |  

A standing wave is formed by the superposition of two waves travelling in opposite directions.  The transverse displacement is given by

y\left ( x,t \right )= 0.5\sin \left ( \frac{5\pi }{4} x\right )\: \cos \left ( 200\pi t \right )                       

What is the speed of the travelling wave moving in the positive x direction ?

(x and t are in meter and second, respectively.)

  • Option 1)

     160 m/s

  • Option 2)

    90 m/s

  • Option 3)

    180 m/s

  • Option 4)

     120 m/s

     

 
As discussed in @7297 Speed of the travelling wave in the X direction will be 160 ms-1 Option 1)  160 m/s This option is correct Option 2) 90 m/s This option is incorrect Option 3) 180 m/s This option is incorrect Option 4)  120 m/s   This option is incorrect
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