A billiard ball. unless hit, the balls stay at rest. however when hit into another, the balls do not stop unless acted upon by another force.
The main reason why it's very dangerous to open compress gas tank is it can cause major disaster not only in human but also in plants and animals. Compress gas is flammable. And it's like a bomb the damage of gas tank is very catastrophic. It is very harmful if mishandled.
We do not feel the gravitational forces from objects other than the Earth because they are weak.
