Ncert Exercises & Solutions

Match the following physical quantities with units.

Codes

Hint: Unit of Luminous intensity=candela

Explanation:

A. Molarity=concentration in mol L^-1

Molarity = Number

of

moles Volume

in

litres

$Molality = concentration$ $in$ $mole$ $pre$ $kg$ $solvent$
$Molality = Number$ $of$ $moles Mass$ $of$ $solvent$ $(kg$

C. The SI unit for pressure is the pascal (Pa), equal to one newton per square metre (N/m² or kg. m^-1 s^-2). This special

name for the unit was added in 1971; before that, pressure in SI was expressed simply as N/m².

D. Unit of luminous intensity=candela

The candela is the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency

540 \times 10^{12}

hertz and that has a radiant intensity in that direction of 1/683 watt per steradian.

So, the correct answer is option 2.