Based on star counts, 100 years ago most astronomers thought:

A) we lay about 30,000 ly out from the center of the Galaxy.
B) we lay near the center of a disk about 10 kpc wide and 2 kpc thick.
C) we lay in a spiral arm of the largest galaxy in the universe.
D) we lay near the edge of the only galaxy in the universe.
E) we were not a part of any structure larger than the known solar system.


B

Physics & Space Science

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The energy dissipated in a light bulb in a circuit is provided by the

A) lamp filament itself. B) wires leading to the lamp. C) voltage source. D) none of the above

Physics & Space Science

A teacher sends her students on a treasure hunt. She gives the following instructions: 1. Walk 300 m north 2. Walk 400 m northwest 3. Walk 700 m east-southeast and the treasure is buried there

As all the other students walk off following the instructions, Jane physics student quickly adds the displacements and walks in a straight line to find the treasure. How far and in what direction does Jane need to walk? A) 187 m in a direction 67.3° north of east B) 481 m in a direction 40.9° north of east C) 399 m in a direction 52.5° north of east D) 284 m in a direction 28.2° west of north E) The treasure position cannot be reached in one straight walk.

Physics & Space Science

What percentage of the Solar wind is hydrogen (H)? This is just the ratio of hydrogen to everything expressed as a percentage.

What will be an ideal response?

Physics & Space Science

Daisy raises 10.Kg to a height of 2.5 meters in 2.0 seconds. (a) How much work did she do? (b) How much power was expended? (c) If she raises it in 1.0 s rather than 2.0 s, how do the work and power change?

What will be an ideal response?

Physics & Space Science