A Spaceship from Another Galaxy Passes Over the Solar System

question 23

Multiple Choice

A spaceship from another galaxy passes over the solar system directly above a radial line from the Sun to the Earth. (We measure that distance to be 1.5 × 1011 m.) On Earth, the spaceship is observed to be traveling at a speed of 0.80c, for which γ = 5/3. As measured on Earth it takes the spaceship 625 seconds to travel from the Sun to Earth. When a scientist in the spaceship measures the Earth-Sun distance and the time it takes her to travel that distance, she finds the results are, respectively

• A)9.0 × 1010 m; 375 s.
• B)9.0 × 1010 m; 625 s.
• C)1.5 × 1011 m; 625 s.
• D)2.5 × 1011 m; 625 s.
• E)2.5 × 1011 m; 1042 s.

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Definitions:

Radio Waves

Electromagnetic waves with longer wavelengths than infrared light, commonly used in communication systems.

Visible Light

The portion of the electromagnetic spectrum that is visible to the human eye, typically wavelengths from 380 to 750 nanometers.

Plant Growth

is the process of increase in size, number of cells, weight, or volume in plants, often influenced by environmental factors.

Chloroplasts

Organelles found in plant and algal cells that conduct photosynthesis, converting light energy, carbon dioxide, and water into glucose and oxygen.