Which of the following is the most important cause for the extinction of animals and plants?

$A, B$ and $C$ are three points in a uniform electric field as shown in the figure. The electric potential is

$A$ motorcyclist of mass $m$ is to negotiate a curve of radius $r$ with a speed $v$. The minimum value of the coefficient of friction so that this negotiation may take place safely,is

If the pair of straight lines $6x^2 - 5xy + y^2 = 0$ makes angles $\alpha$ and $\beta$ with the $X$-axis,then $\tan(\alpha - \beta) = $

$[Co(NH_3)_4(NO_2)_2]Cl$ exhibits

If a force $F$ is applied on a body and it moves with a velocity $v$,the power will be