The mass of a hydrogen molecule is 3.32 × 10-27 kg. If 1023 hydrogen molecules strike, per second,a fixed wall of area 2 cm2 at an angle of 45° to the normal, and rebound elastically with a speed of 103 m/s , then the pressure on the wall is nearly :

Question

The mass of a hydrogen molecule is 3.32 × 10-27 kg. If 1023 hydrogen molecules strike, per second,a fixed wall of area 2 cm2 at an angle of 45° to the normal, and rebound elastically with a speed of 103 m/s , then the pressure on the wall is nearly : (A) 2.35 × 103 N/m2 (B) 4.70 × 103 N/m2 (C) 2.35 × 102 N/m2 (D) 4.70 × 102 N/m2

Tardigrade Admin · Accepted Answer

P=(F/A)=(2 ⋅ n m v cos θ/A) =(2 × 1023 × 3.32 × 10-27 × 103/√2 × 2 × 10-4) N / m 2 =2.35 × 103 N / m 2

Q. The mass of a hydrogen molecule is $3.32 \times 1 0^{- 27} k g$ . If $1 0^{23}$ hydrogen molecules strike, per second,a fixed wall of area $2 c m^{2}$ at an angle of $4 5^{\circ}$ to the normal, and rebound elastically with a speed of $1 0^{3} m / s$ , then the pressure on the wall is nearly :

$2.35 \times 1 0^{3} N / m^{2}$

$4.70 \times 1 0^{3} N / m^{2}$

$2.35 \times 1 0^{2} N / m^{2}$

$4.70 \times 1 0^{2} N / m^{2}$

$P = \frac{F}{A} = \frac{2 \cdot nm v c o s θ}{A}$
$= \frac{2 \times 1 0 ^{23} \times 3.32 \times 1 0 ^{- 27} \times 1 0 ^{3}}{2 \times 2 \times 1 0 ^{- 4}} N / m^{2}$
$= 2.35 \times 1 0^{3} N / m^{2}$

Q. The mass of a hydrogen molecule is 3.32×10−27kg. If 1023 hydrogen molecules strike, per second,a fixed wall of area 2cm2 at an angle of 45∘ to the normal, and rebound elastically with a speed of 103m/s , then the pressure on the wall is nearly :

2.35×103N/m2

4.70×103N/m2

2.35×102N/m2

4.70×102N/m2