A dentist uses a concave mirror (focal length 2 cm) to examine some teeth. If the distance from the object to the mirror is 1 cm, what is the magnification of the tooth?
a. 6
b. 1
c. 4
d. 2
e. 1.5
d
You might also like to view...
A line drawn through locations of equal atmospheric pressure is a(n)
a. equipress. b. anemometer. c. wind vane. d. isobar.
Why is the Moon's cycle of phases (the synodic month) longer than the Moon's orbital period (the sidereal month)?
A) The Moon completes the cycle of lunar phases before it completes a full orbit around Earth. B) The Moon has to complete more than one full orbit around Earth to complete the cycle of lunar phases. C) The Moon orbits Earth faster than Earth orbits the Sun. D) The Moon orbits Earth faster than Earth rotates. E) The lunar month is based on the Moon's orbit, while the sidereal month is based on Earth's orbit.
How did Brahe measure highly accurate planetary positions?
A) By careful measurements of the brightness of the planets, as seen from Earth. B) With larger and more elegant sighting instruments. C) By his invention of the technique know as triangulation (measuring the distance between 2 points, and measuring 2 angles, to determine the distance to a 3rd point). D) With the recently-invented telescope. E) With a new type of telescope that used mirrors instead of lenses.
Silicates
a. are minerals. b. contain silicon and oxygen. c. consist of tetrahedra. d. all of the above.