A roller coaster with a mass of 800 kg sits stationary at the top of a section of track, 75 m above the ground as shown. When the brake is released, it starts to roll down the track. For each height indicated in the diagram, calculate the gravitational potential energy and record in the table. Assuming that there is no friction, determine the mechanical kinetic energy and calculate the velocity for each of the heights of the rollercoaster and record in the table. height is 75m, 60m, 45m, 30m,15m.

Match the atomic particles with their characteristics. 1. made of two protons and two neutrons neutron 2. similar to an electron; positive charge neutrino 3. orbits nucleus; negative charge positron 4. bundle of energy; zero charge proton 5. found in nucleus; positive charge meson 6. very unstable; +, -, or zero charge gamma 7. found in nucleus; zero charge electron 8. negative particle; negative charge beta 9. atomic energy converted to mass alpha

Asheet of steel 1.5 mm thick has nitrogen atmospheres on both sides at 1200oc and is permitted to achieve a steady-state diffusion condition. the diffusion coefficient for nitrogen in steel at this temperature is 6 x 10- 11 m2 /s, and the diffusion flux is found to be 1.2 x 10-7 kg/m2 -s. also, it is known that the concentration of nitrogen in the steel at the high-pressure surface is 4 kg/m3 . how far into the sheet from this high-pressure side will the concentration be 2.0 kg/m3 ? assume a linear concentration profile.

In a series circuit the __ is the same at every point