The mutual inductance of a pair of solenoids depends on

The resistivity of an iron wire is \( 10 \times 10^{-8} \, \Omega \text{ m} \). The resistance of an iron wire is \( 5 \, \Omega \). If its length as well as thickness is doubled then its resistivity will be :

An electron enters a crossed electrical and magnetic field region with a speed of \( 100 \text{ m s}^{-1} \) along \( +x \)-axis and passes undeviated. The strength of magnetic field is 5.0 T and it acts along \( +z \)-axis. Give the electrical field in vector notations indicating its magnitude as well as direction :

A charge q is moving with velocity \( \vec{v} \) in the presence of both electric field \( \vec{E} \) and magnetic field \( \vec{B} \). If velocity (\( \vec{v} \)), electric field (\( \vec{E} \)) and the magnetic field (\( \vec{B} \)) are mutually perpendicular. The charge will pass through the field undeflected if :

For a metre Bridge, Choose the incorrect option from the following

Two identical point charges placed at a distance 'r' apart exert a force F on each other. If each charge is halved and the distance between them is doubled, then the new force acting on each charge would be

An electric dipole of moment P is placed along the direction of electric field E. The work done in deflecting the dipole through 180° is equal to

If \(y=3 \cos (\log x)+4 \sin (\log x)\), then choose correct option :

Alcohol is a depressant, which means that even small amounts of alcohol slow down the actions of parts of the brain, so alcohol lengthens the time you take to respond to a stimulus.
Different people react differently to alcohol. In some people, it increase their feelings of aggression, and releases their inhibitions so that they are more likely to be violent or commit other crimes.
An alcoholic needs to drink quite large quantities of alcohol regularly. This causes many parts of the body to be damaged, because alcohol is poisonous to cells. Probably, there are many factors which decide whether or not a person becomes alcoholic. Over a long period of time, it can cause loss of memory and confusion. One way in which the damage is done is that alcohol in the body fluids draws water out of cells by osmosis.
Alcohol lengthens the time one takes to respond to a stimulus. This occurs due to

Which of the following enzyme is used during isolation of DNA from fungal cells?

The resistance of a wire is \( R \, \Omega \). What will be its new resistance \( R_{new} \) if it is stretched to n times its original length?

A coin is biased so that head is 4 times as likely to occur as tails. If X represents the number of heads when coin is tossed 4 times then \(P(X=2)\) is equal to:

Correct order of the following acids in order of their increasing acidic strength is
(A) \(CCl _3 COOH\)
(B) \(ClCH _2 COOH\)
(C) \(CH _3 COOH\)
(D) \(CHCl _2 COOH\)
Choose the correct answer from the options given below: