A rock from a volcanic eruption is launched straight up into the air with no appreciable air resistance. Which one of the following statements about this rock while it is in the air is correct?
A) On the way up, its acceleration is downward and its velocity is upward, and at the highest point both its velocity and acceleration are zero.
B) On the way down, both its velocity and acceleration are downward, and at the highest point both its velocity and acceleration are zero.
C) Throughout the motion, the acceleration is downward, and the velocity is always in the same direction as the acceleration.
D) The acceleration is downward at all points in the motion.
E) The acceleration is downward at all points in the motion except that is zero at the highest point.
D
You might also like to view...
Which of the following is an example of a galaxy?
A) The Canopus Galaxy B) The Milky Way Galaxy C) The Proxima Centauri Galaxy D) The Alpha Centauri Galaxy
The _________ coincides with the period known as the "little ice age" of Europe and North America. This provides one piece of evidence that suggests a link between solar activity and the amount of solar energy Earth receives
a. Maunder sunspot minimum b. Babcock sunspot model c. coronal hole d. Coulomb barrier e. weak solar force
All classes of binary stars yield the basic information on stellar ________
Fill in the blank(s) with correct word
What is the meaning of the term "critical mass" in regard to nuclear fission?
A) This is the mass of the "critical" elements in a reactor, i.e., the uranium or plutonium. B) This is the amount of mass needed to make a power reactor economically feasible. C) This is the amount of material that is just on the verge of becoming radioactive. D) This is the minimum amount of fissionable material required to sustain a chain reaction.