If P represents radiation pressure, c repr

Your Ultimate Guide to JEE & NEET Question Solutions

If $P$ represents radiation pressure, $c$ represents speed of light and $Q$ represents radiation energy striking a unit area per second, then non-zero integers $x,\,y$ and $z$ such that ${P^x}{Q^y}{c^z}$ is dimensionless, are

A

$x = 1,\,\,y = 1,\,\,z = - 1$

B

$x = 1,\,y = - 1,\,z = 1$

C

$x = - 1,\,y = 1,\,z = 1$

D

$x = 1,\,y = 1,\,z = 1$

If $P$ represents radiation pressure, $c$ represents speed of light and $Q$ represents radiation energy striking a unit area per second, then non-zero integers $x,\,y$ and $z$ such that ${P^x}{Q^y}{c^z}$ is dimensionless, are

By substituting the dimension of given quantities

${[M{L^{ - 1}}{T^{ - 2}}]^x}{[M{T^{ - 3}}]^y}{[L{T^{ - 1}}]^z} = {[MLT]^0}$

By comparing the power of $M, L, T$ in both sides

$x + y = 0$ .....$(i)$

$ - x + z = 0$ .....$(ii)$

$ - 2x - 3y - z = 0$ …$(iii)$

The only values of $x,\,y,\,z$ satisfying $(i),$ $(ii)$ and $(iii)$ corresponds to $(b).$