How do we harness the energy found in hydrogen to power fuel cells?

An incident ray through the focal point of a spherical mirror will: reflect through the center of curvature. reflect back through the focal point. reflect parallel to the principle axis. reflect the same direction as the incident ray.

Aprotein molecule in an electrophoresis gel has a negative charge. the exact charge depends on the ph of the solution, but 30 excess electrons is typical. what is the magnitude of the electric force on a protein with this charge in a 1600n/c electric field? write in two significant numbers, and also in newton

What’s the kinetic energy of the object? use . erica is competing in the shot put event at a track meet. she hurls a shot with a mass of 4 kilograms at a speed of 9 meters/second. the shot’s kinetic energy is joules.