A new generation of ground-based telescopes is currently being built that overcomes the limitations of the older large telescopes. Some of these new telescopes
a. use segmented mirrors.
b. use mirrors that are very thin.
c. use active optics to control the shape of the mirror.
d. all of the above.
e. none of the above
D
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A binary star system in the constellation Orion has an angular separation between the two stars of 1.2 × 10?5 radians. If ? = 5 × 10?7 m, what is the smallest-aperture (diameter) telescope that may be used to resolve the two stars?
A. 10 cm B. 5 cm C. 50 cm D. 1 m E. 4 cm
Enzo throws a rock horizontally with a speed of 12 m/s from a bridge. It falls for 2.28 s before reaching the water below with no appreciable air resistance. Just as the rock reaches the water, find
(a) the horizontal component of its velocity. (b) the speed with which it is moving.
An object of length 3.00 cm is inside a plastic block with index of refraction 1.40 . If the object is viewed through the top surface of the block at a non-zero angle from the normal, where is the object relative to its image?
a. in the same direction as its image b. above the direction of its image c. below the direction of its image d. More information is needed.
A firecracker breaks up into two pieces, one of which has a mass of 200 g and flies off along the +x-axis with a speed of 82.0 m/s. The second piece has a mass of 300 g and flies off along the +y-axis with a speed of 45.0 m/s
What is the total momentum of the two pieces? A) 361 kg ? m/s at 56.3° from the +x-axis B) 93.5 kg ? m/s at 28.8° from the +x-axis C) 21.2 kg ? m/s at 39.5° from the +x-axis D) 361 kg ? m/s at 0.983° from the +x-axis E) 21.2 kg ? m/s at 56.3° from the +x-axis