Light travels at a speed if 186,000 miles per second. A light-year is the distance that light travels in one year. What is the distance of a light year (in miles)?

What happens to atoms and chemical bonds during a reaction?

The first law of thermodynamics states that heat added to a system is neither created nor destroyed but is as it changes into other forms of energy.

An alpha particle with kinetic energy 12.5 mev makes a collision with lead nucleus, but it is not "aimed" at the center of the lead nucleus, and has an initial nonzero angular momentum (with respect to the stationary lead nucleus) of magnitude l = p0 b, where p0 is the magnitude of the initial momentum of the alpha particle and b=1.40×10−12 m. (assume that the lead nucleus remains stationary and that it may be treated as a point charge. the atomic number of lead is 82. the alpha particle is a helium nucleus, with atomic number 2.) what is the distance of closest approach?