Suppose two galaxies move away from each other at 6000 km / sec and are 300 million (3 ×10^8) li

step 1 In this problem, the distance between Earth and the center of galaxy as measured by the stationa

Suppose two galaxies move away from each other at 6000 km /...

Suppose two galaxies move away from each other at 6000 $\mathrm{km} / \mathrm{sec}$ and are 300 million $\left(3 \times 10^{8}\right)$ light-years apart. If their speed has remained constant, how long has it taken them to move that far apart? Express your answer in years.

Key Concepts

Speed-Distance-Time Relationship

This fundamental concept in kinematics states that time can be computed by dividing distance by speed. In any problem where a constant speed is assumed, calculating how long it takes to cover a certain distance involves directly applying this relationship, making it a core principle in both classical mechanics and everyday calculations.

Unit Conversion

In physics and astronomy, it is essential to convert between different units to ensure consistency in calculations. Here, the distance given in light-years must be converted to the same unit as the speed (kilometers) so that the division is valid. This concept underscores the importance of understanding and applying conversion factors between units like light-years and kilometers.

Astronomical Distance Units

Astronomical units such as the light-year are used to express the immense distances found in space. A light-year is defined as the distance light travels in one year. Recognizing and converting these astronomical units is crucial for solving problems related to cosmic distances and timescales, which often differ drastically from everyday measurements.

Constant Velocity Assumption

The assumption that speed remains constant simplifies the problem by allowing the direct application of the speed-distance-time formula without considering acceleration, deceleration, or gravitational influences. This idealized situation aids in extracting approximate timescales in astronomical contexts, even though in reality, forces like cosmic expansion may vary over time.

Transcript

Please give Ace some feedback