Friction . 1.happens whenever work is done
2.does not happen in the air
3.releases energy as light
4.absorbs heat energy

Mike walks 100 meter north, then walks 30 meters south. after this, he walks another 10 meters north. what is the magnitude of his total displacement during this walk, in meters?

In a good thermo flask the main cause of heat loss is

What is similar between metals and suspensions