Question

8 m³ of a gas is heated at the pressure 10⁵ N/m² until its volume increases by 10%. Then, the external work done by the gas is ____________.

Options

• 4 x 10⁵ J

• 8 x 10⁴ J

• 10⁴ J

• 10⁶ J

Answer 1

8 m³ of a gas is heated at the pressure 10⁵ N/m² until its volume increases by 10%. Then, the external work done by the gas is 8 x 10⁴ J.

Explanation:

`"External work done" = "pdV" = "P" ("V"_2 - "V"_1)`

`"V"_1 = "V" = 8"m"^3 "and"`

`"V"_2 = "V" + 10 %  "V" = "V" + (10"V")/100`

`therefore "W" = "P" ("V" + (10"V")/100-"V")`

`= (10"PV")/100 = 0.1 xx 10^5 xx 8`

`= 8 xx 1064 J`