Vessels and Companion cells are characteristics of

An ideal transformer has $100$ turns in the primary and $250$ turns in the secondary. The peak value of the $AC$ voltage in the primary is $28\ V$. The $r.m.s.$ secondary voltage is nearest to $....V$.

Which of the following reactions is $NOT$ associated with the Solvay process for the manufacture of sodium carbonate?

Heat required to melt $1\, g$ of ice is $80\, cal$. $A$ man melts $60\, g$ of ice by chewing in one minute. His power is ........ $W$.

If the line $y=2x+c$ is a tangent to the circle $x^2+y^2=5$,then a value of $c$ is

$A$ particle is released from a height $H$. At a certain height,its kinetic energy is half of its potential energy with reference to the surface of the earth. The height and speed of the particle at that instant are respectively: