Approximately how fast do artificial satellites in low Earth orbit travel around the Earth in order to stay in orbit?

Introduction / Context:
Artificial satellites travel at very high speeds to remain in orbit around the Earth. Knowing the approximate orbital speed helps you appreciate the scale of space technology and is a common fact tested in general science. Low Earth orbit satellites, such as many weather and communication satellites, have a typical speed that balances gravitational pull and centrifugal effect.

Given Data / Assumptions:

• The question asks how fast satellites orbit the Earth.
• We focus on typical low Earth orbit speeds.
• The options are given in kilometres per hour.

Concept / Approach:
A satellite in low Earth orbit, a few hundred kilometres above the surface, completes one orbit roughly every 90 minutes. To travel once around the Earth in that time, it must move at a speed of about 7.8 kilometres per second. When converted, this is roughly 28,000 kilometres per hour. The answer choices reflect different possible speeds, but the one closest to this standard figure is 28,000 km/h.

Step-by-Step Solution:
Step 1: Recall that low Earth orbit period is about 90 minutes for many satellites. Step 2: Use the rough circumference of Earth, about 40,000 kilometres. Step 3: If a satellite covers about 40,000 kilometres in one and a half hours, its speed must be around 40,000 km divided by 1.5 h. Step 4: This gives approximately 26,000 to 27,000 km/h, and more precise calculations give about 28,000 km/h. Step 5: Match this with the options and choose 28,000 km/h as the closest typical orbital speed.

Verification / Alternative check:
Another check is to recall that many sources report satellite orbital speeds as about 7.8 kilometres per second. Multiplying 7.8 by 3,600 seconds per hour gives about 28,000 kilometres per hour. This independent method supports the same answer and confirms that 28,000 km/h is correct for this question.

Why Other Options Are Wrong:
Option B, 26,000 km/h, is slightly lower than the typical speed and would not match the most widely quoted value. Option C, 17,500 km/h, is much too low for a stable low Earth orbit. Option D, 22,500 km/h, is also significantly lower than the required orbital speed. Option E, 8,000 km/h, is far too slow and would not keep a satellite in orbit at low altitude.

Common Pitfalls:
Learners may confuse speeds given in kilometres per hour and kilometres per second, or they may underestimate how fast satellites move because the motion looks slow in the night sky. Remember that satellites are very high above Earth, so even at extreme speeds they seem to move smoothly. Keeping the approximate value of 7.8 kilometres per second or 28,000 kilometres per hour in mind will help you answer similar questions correctly.

Final Answer:
Artificial satellites in low Earth orbit travel at about 28,000 km/h around the Earth.