The forces acting on a falling leaf are
a. gravity and static friction.
b. gravity and air resistance.
c. weight and rolling friction.
d. air resistance and fluid friction.

Estimate the schwarzschild radius (in kilometers) for a mini-black hole formed when a superadvanced civilization decides to punish you (unfairly) by squeezing you until you become so small that you disappear inside your own event horizon. (assume that the your weight is 50 kg)

Which of the following correctly describes what happens when an atomic bomb explodes? small pieces of fissionable material are joined and form a body with a mass greater than the critical mass, the relative number of neutrons escaping decreases, and a chain reaction and explosion result. large pieces of fissionable matter are brought together quickly and form a body with a mass smaller than the critical mass, the relative number of escaping neutrons increases, and a chain reaction and explosion result.

Which best describes what forms in nuclear fission? a. two smaller, more stable nucleib. two larger, less stable nucleic. one smaller, less stable nucleusd. one larger, more stable nucleus