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Who noticed the deflection of the compass needle every time the current was passed through the wire? When an electric current flows through a wire, it behaves like a magnet.

Hans Christian Oersted was the first person who noticed the deflection of the compass needle every time the current was passed through the wire. When an electric current flows through a wire, it behaves like a magnet.
It can be done by Connecting a large Resistance R in series with the Galvanometer

what is the difference between the two ?

The prefix poly means many. So the word polynomial refers to one or more than one term in an expression. The relationship between these terms may be sums or differences. You call expression with a single term a monomial, an expression with two terms is a binomial, and expression with three terms is a trinomial. Here we are only discussing Binomial along with their exponents.

pressure inside a liquid jet in excess of atmostpheric pressure . for example if aglass tube of samll diameter is partially immersed in water , the water will wet the surface of the tube ant it will rise in the tube to some height above the normal water surface . In this case, the water surface is concave upward.

 

  • In this collision (K.E)_{initial} \neq (K.E.)_{final}

  • Coefficient of restitution 0 < e < 1 

  • As (K.E)_{initial} > (K.E.)_{final}

The loss in kinetic energy appears in other forms, such as heat, sound etc. 

Ex- Collision between two billiard balls. All majority of collision belong to this category.

in inelastic collision k. e. is conserved

If not then the loss in kinetic energy is transferred into which form of energy??

Work

 

A massless rope is fixed at one end as shown in fig. Two boys of masses 40kg and 60kg are moving along the rope. The former climbing up with an accelaration of 2m/s^2 while  later coming down with constant velocity of 5m/s. The tension at fixed support will be (g=10m/s^2)

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...

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   

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 
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

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 ?

or  

10 identical cell in series are connected to the ends of a resistance of 59\Omega,the current is  found to be 0.25A. But when the same cells being connected in parallel,are joined to the ends of a resistance of 0.05\Omega,the current is 25A EMF of  each cell is

A.

1V

B.

0.5V

C.

1.5V

D.

2V

 In series:  In parallel:  (1)-(2)

Question

Two finite sets have m and n elements. The total number  subsets of first set is 56 more than second set, find m and n.

A.

7,6

B.

6,3

C.

5,1

D.

8,7

Magnetic field through a coil is changed with respect to time then emf induced in it then select the incorrect regarding induced emf in coil

\begin{array}{l}{\text { Coil may be made up with wood }} \\ {\text { Coil may be connected with an open circuit }} \\ {\text { Coil must be of conducting nature }} \\ {\text { Induced emf does not depends upon resistance }} \\ {\text { the coil }}\end{array}

Option (1) is Incorrect as the coil must be made of conducting substance if we want to induce emf and pass current through it.
1560259998516566813835.jpg

@Vinod

\\\int \sqrt{\frac{\sin \left(x-a\right)}{\sin \left(x+a\right)}}dx\\rationalize\;it\\\int \sqrt{\frac{\sin \left(x-a\right)\sin \left(x-a\right)}{\sin \left(x+a\right)\sin \left(x-a\right)}}dx\\\int \frac{\sin \left(x-a\right)}{\sqrt{\sin \:\left(x+a\right)\sin \:\left(x-a\right)}}dx\\\because \sin \left(A+B\right)\sin \left(A-B\right)=\sin ^2A-\sin ^2B\\\int \frac{\sin x\:\cos a-\sin a\:\cos x}{\sqrt{\sin ^2x-\sin ^2a}}dx\\\cos a\int \frac{\sin x\:}{\sqrt{\sin ^2x-\sin ^2a}}dx\:-\sin a\int \:\frac{\:\cos \:x}{\sqrt{\sin \:^2x-\sin \:^2a}}dx\:\:\:

\\\cos a\int \frac{\sin x\:}{\sqrt{\sin ^2x-\sin ^2a}}dx\:\\\cos \:a\int \frac{\sin \:x\:}{\sqrt{1-\cos ^2x-1+\cos ^2a}}dx\:\\\Rightarrow \cos \:a\int \frac{\sin \:x\:}{\sqrt{\cos \:^2a-\cos ^2x}}dx\:\\put\;\cos x=t,and\;solve\\same\;method\;apply\;for\;\sin a\int \:\frac{\:\cos \:x}{\sqrt{\sin \:^2x-\sin \:^2a}}dx\:\:\:

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