A proton, of mass m and speed v, strikes an alpha-particle (which consists of 2 protons and 2 neutrons) at rest.
If the collision is completely elastic, what speed will the -particle have after the collision? (Assume the neutron's mass equals the proton's mass.) A) zero
B) 3/2 v
C) 2/5 v
D) 2/3 v
E) 5/3 v
Question 2Which is NOT a critical factor that determines the habitability of a rocky planet?
A) size
B) distance from parent star
C) presence of a magnetic field
D) presence of an atmosphere
Question 3When a liquid evaporates
A) the temperature of the substance increases.
B) the temperature of the substance decreases.
C) heat energy leaves the substance.
D) heat energy enters the substance.
Question 4The Rare Earth Hypothesis suggests that
A) the circumstances that have allowed life on the Earth to appear and develop may be so rare that it is unlikely to have occurred anywhere else
B) Earth and life on it were created by some omnipotent being
C) the orbits of any Earth-like planets around other stars would have been disrupted by inward migration of Jovian planets
D) Earth-like planets are unlikely to have formed around any other stars
Question 5In general, sound is conducted fastest through
A) gases.
B) liquids.
C) solids.
D) a vacuum.
Question 6Granite is a common type of
A) meteoritic rock
B) metamorphic rock
C) igneous rock
D) sedimentary rock