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Nucleophilicity is highest in polar aprotic solvents, and lower in polar protic solvents because polar protic solvents (like water) can make H-bond and it will ultimately make the nucleophile more bulky. E.g. of polar protic solvents - H2O, CH3OH, CH3CH2OH, CH3COOH, H2SO4 E.g. of polar protic solvents - DMSO, Acetone, DMF, HMPA, Acetonitrile  If the solvent is polar aprotic, it’s safe to assume...

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Physics has many definitions. In simple words Physics is branch of science concerned with the nature and properties of matter and energy

phsiyics is consist of all kind of physical property   

You just finished Kinematics

In this chapter, you have completed: 19 concepts 17 doubts More than 30 Questions and Examples In this chapter, firstly you read Concepts of “Kinematics” and then moved to “applications of kinematics”. Apart from this, there are certain tips for you which will be helpful for you to develop a lot of interest in this chapter. There are some examples as well as practise question in each...
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in a stretched string the speed of wave is 20m/s ` frequency 50hz . the find the phase difference in vibration of two point at string situate 10cm

The wavelength  and 

Time (T), velocity (C) and angular momentum (h) are chosen as fundamental quantities instead of mass, length and time. In terms of these, the dimensions of mass would be :

Dimension of length 
A bivalent of meiosis-I consists of a pair of homologous chromosomes, that is, there are tetrads of chromatids and bivalent of chromosomes.

What is a cell?

What is the difference between pleiotropy and polygenic inheritance

Q. What is the difference between molarity and normality?

Molarity based on vol. Of solvent in 100litre of solu. While normality is gram molecular mass

Capacitance in a medium


K=C'/ C=110/50=2.2

C' = KC C' = 110pF , C = 50pF 110 = K x 50 K= 110/50 = 2.2  Thus, K = 2.2[no units]  for oil

A man of mass (m_A) is sitting in a train movingwith velocity v_1 = 3 m/s . He observe that a block of mass m_B is moving towards him with velocity v_2 = 5 m/s. Then the kinetic energy of block w.r.t  man is (Assume m _B= 5 Kg)

 K.E of the block from the reference frame of the train is 

A block of mass m is kept on a platform which starts from rest with constant acceleration g/2 upward, as shown in the figure. Work done by normal reaction on block in time t is:

By balancing the forces in vertical direction, we get: and displacement is given by equation: where u=0 and a=g/2 and we know,

When the rms voltages VL, VC and VR are  measured respectively across the inductor L, the capacitor C and the resistor R in a series  LCR  circuit  connected  to  an AC source, it is found that the ratio VL : VC : VR = 1 : 2 : 3. If the rms voltage of the AC source is 100 V, then VR is close to ?

Are there any other states of matter exist other than Solid, Liquid and Gasses?
Yes. There are five known Phases or States of the matter: solids, liquids, gases, plasma, and Bose-Einstein condensates. You will study these in higher classes.

When both arms are parallel. 

Let 2θ be the angle between the arm 2T cos θ = mg T = mg/2cosθ Tension when cos θ is mass. this achieved when θ = 0 T = mg/2 = 40×10/2 = 200 N The both arm should be parallel ..ll.e. either 0 or 360.  

     Write these in ascending and also in descending order.

              (a)  \frac{1}{8},\frac{5}{8},\frac{3}{8}

             (b)  \frac{1}{5},\frac{11}{5},\frac{4}{5},\frac{3}{5},\frac{7}{5}

            (c)  \frac{1}{7},\frac{3}{7},\frac{13}{7},\frac{11}{7},\frac{7}{7}

option A