Your friend drops your house keys down to you from their second floor window. If you catch them 2.4 m from where your friend dropped them, what is the velocity of the keys when you catch them? a.
-6.9 m/s
c.
-7.2 m/s
b.
-6.5 m/s
d.
-7.4 m/s

Which are advantages of renewable resources? check all that apply. renewable energy supplies are completely reliable everywhere. some renewable resources will never be used up. little or no waste is produced by renewable resource plants. electricity can be generated in large quantities. many renewable energy facilities have lower operating costs.

What are the starting materials for nuclear fission? two small nuclei two large nuclei a neutron and a large nucleus a neutron and a small nucleus

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?