Answer: Three forces act significantly on a freely floating helium-
filled balloon: gravity, air resistance (or drag force), and a
buoyant force.
Explanation:
The air pressure on the bottom of the balloon is slightly higher than the air pressure on the top of the balloon (because of the altitude difference). This difference gives rise to the bouyant force. This force competes with gravity as the two main forces acting on the balloon. Every time your feet hit the ground when you are running, the ground hits your feet with an equal and opposite force. Newton’s third law explains how balloons and rocket engines work. When the neck of an inflated balloon is released, the stretched rubber material pushes against the air in the balloon. The air rushes out of the neck of the balloon.
Answer:
c - the frequency of the waves decreases
The heat energy is used to overcome the inter-molecule force of attraction but when this inter molecule is broken it changes state and the temperature starts increasing
Astatine is a metalloid but sometimes it is classified as a metal or non-metal. However, Astatine is irregularly classified as a metalloid.
