Pencil "lead" (graphite) is made primarily of
a. oil.
b. PbO2.
c. carbon.
d. Pb.
c
You might also like to view...
An electron moving from the negative terminal to the positive terminal of a 12. volt battery gains (or loses) how much energy? (Be sure to indicate whether it is a gain or loss.)
What will be an ideal response?
When we say that a material sample has reached its elastic limit, we mean that
A) if any further stress is applied, the sample will break. B) if any further stress is applied, the deformation of the sample will not be reversible. C) the deformation no longer follows Hooke's law. D) the material will continue deforming with no further additional stress. E) None of the other choices is correct.
Equipotentials are lines along which
A. the electric field is constant in magnitude and direction. B. the electric charge is constant in magnitude and direction. C. maximum work against electrical forces is required to move a charge at constant speed. D. a charge may be moved at constant speed without work against electrical forces. E. charges move by themselves.
Any change of the energy of a system occurs because of
a. energy transfer across the boundaries of the system. b. combustion of fuels within the system. c. radioactive decay of elements within the system. d. all of the above. e. only (b) and (c) above.