Question

A car tire contains 0.0320 m3 of air at a pressure of 2.35 ✕ 105 N/m2 (about 34 psi). How much more internal energy (in J) does this gas have than the same volume has at zero gauge pressure (which is equivalent to normal atmospheric pressure)? (Assume the tire pressure of 2.35 ✕ 105 N/m2 is absolute pressure, not gauge pressure. Assume for this question that air is monatomic.)

Answer 1

The internal energy in the system is

ΔE = 1.072 x 10 ⁴ J

Step-by-step explanation:

Given

V = 0.0320 m³

P₁ = 2.35 x 10 ⁵ Pa

P₂ = 1.01 x 10 ⁵ Pa

To determine the internal energy

ΔE = ⁵/₂ * V * ( P₂ - P₁ )

ΔE = ⁵/₂ * 0.0320 m³ * ( 2.35 x 10 ⁵ - 1.01 x 10 ⁵ ) Pa

ΔE = ⁵/₂ * 0.0320 m³ * (134 kPa)

ΔE = 10720 J

ΔE = 1.072 x 10 ⁴ J