Question

An insulated box containing helium gas falls from a balloon 4.5 km above the earth's surface. calculate the temperature rise in ℃ of the helium when box hits the ground. A. 15.2 B. 12.6 C. 25.3 D. 14.1

Answer 1

Answer:

The rise in temperature of helium gas is 14.25 K.

Explanation:

Given that

H= 4.5 km

The box is insulated ,at 4.5 km height helium gas have potential energy and when it come down then this potential energy will convert into the internal energy of helium gas.

So by heat balance

$mgh=mC_v\Delta T$

$gh=C_v\Delta T$

$C_v=3.15\frac{KJ}{kg.K}$ for helium gas

Now by putting the values

$gh=C_v\Delta T$

10 x 4.5 =3.15 x ΔT

ΔT=14.25 K

So the rise in temperature of helium gas is 14.25 K.