A790n person runs up a flight of 40 stairs (.25m for each step) in 20 seconds, and then down 10 steps in 5 seconds. how much total mechanical work is completed? how much total mechanical power is generated? show all work.

Red light strikes a metal surface and electrons are ejected. if violet light is now used with a 10% greater intensity, what will happen to the ejection rate (number of ejected electrons per second) and the maximum energy of the electrons? a) greater ejection rate; same maximum energyb) same ejection rate; greater maximum energyc) greater ejection rate; greater maximum energyd) same ejection rate; same maximum energye) none of the above answers are correct

You can estimate the degree to which a bond between two atoms is ionic or covalent by calculating the

What is the moment of inertia i of this assembly about the axis through which it is pivoted? express the moment of inertia in terms of mr