Contrast the main mirrors of Newtonian and Cassegrain designs
What will be an ideal response?
Both use a curved mirror, but the Newtonian has a flat secondary mirror that sends the light to an eyepiece at the side of the telescope, while the Cassegrain mirror is similar, but usually more steeply curved, and needs a hole to be drilled in the center for access to the Cassegrain focus behind this mirror.
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When is an elevator a reasonably good inertial reference frame?
A. Never, under any circumstances. B. Always, since it is attached to the surface of the earth. C. It is good except when it is changing speed. D. Other conditions (describe).
Leaving a hot oven door open in a closed room on a cool day
A) decreases room temperature. B) increases room temperature. C) doesn't affect room temperature.
A proton with a kinetic energy of 0.20 keV follows a circular path in a region where the magnetic field is uniform and has a magnitude of 60 mT. What is the radius of this path?
a. 4.1 cm b. 2.9 cm c. 3.4 cm d. 5.1 cm e. 2.4 cm
What makes some astronomers think that Uranus was hit by a large body early in its history?
A. It has no moons. B. It goes around the Sun in a direction opposite to the other planets. C. Its composition is so different from those of Neptune, Jupiter, and Saturn. D. Its rotation axis has such a large tilt with respect to its orbit. E. All of these choices are correct.