The mass of a hydrogen molecule is $3.32 \times 10^{-27} kg$. If $10^{23}$ hydrogen molecules strike, per second, a fixed wall of area $2\;cm^2$ at an angle of $45^{\circ}$ to the normal, and rebound elastically with a speed of $10^3 m/s$, then the pressure on the wall is nearly :

Question

( A ) $4.70 \times 10^3 N/m^3$
( B ) $2.35 \times 10^2 N/m^2$
( C ) $2.35 \times 10^3 N/m^2$
( D ) $4.70 \times 10^3 N/m^2$