Author Question: A hot air balloon plus its cargo has a mass of 400 kg, and it holds 700 m3 of hot air. It is ... (Read 102 times)

xroflmao · **on:** Jul 29, 2018

A hot air balloon plus its cargo has a mass of 400 kg, and it holds 700 m3 of hot air. It is floating at a constant height in air with a density of 1.29 kg/m3. What is the density of the hot air in the balloon?

A) 1.39 kg/m3
B) 0.72 kg/m3
C) 0.57 kg/m3
D) 0.86 kg/m3
E) 0.43 kg/m3

Question 2

The reflecting surfaces of two plane mirrors are perpendicular to each other. How many images of himself will a person standing at a certain distance from the intersection of these mirrors see?

A) 1
B) 2
C) 3
D) 4
E) 5