Answer to Question #283200 in Physics for leg.end

Question

The pressure of the helium in the balloon is 100 000 Pa. The volume of the balloon is 0.030 m3 . The balloon is compressed at a constant temperature causing the volume to decrease to 0.025 m3 . No helium leaves the balloon. Calculate the new pressure in the balloon

Answer 1

Apply the combined gas law keeping in mind the temperature did not change:

$$\dfrac{PV}T=\dfrac{P_nV_n}T,\\\space\\ PV=P_nV_n,\\\space\\ P_n=\frac{PV}{V_n}=\dfrac{100000·0.03}{0.025}=120000\text{ Pa}.$$