Speed is something with which everyone is familiar. Even though it links to physics, we see speed as a movement rather than lines on a graph. You see it when someone is flying a plane, driving a car, or jogging on the road. You don’t need a scientist to determine when speed is occurring.
You measure vehicle speed in kilometers or miles per hour. You measure boats and planes in knots. If you are a scientist, you might be more familiar with meters per second.
Once you know the measurements of speed, you will see it links to distance and time. Your distance correlates directly to your time, with time dividing it. If you were to simplify the terminology, you would say that speed is the distance traveled per unit of time.
You might see speed as one definition, but it’s several. There’s an average speed, rotational speed, and instantaneous speed. All exist under different circumstances.
Let’s say you are looking at the speed of your vehicle. You’re going 50 kilometers an hour. You know that if you drive at a continuous speed, you will travel 50 kilometers in one hour. Of course, that’s approximate.
With traffic flow and other considerations, it may take you an hour and a bit. If you speed, it would be less. Fifty kilometers per hour would be the average speed of the total distance you travel. What would the speedometer mean, in this case?
The needle in your speedometer measures your current speed. The instantaneous speed is an object position change (x) between two moments in time (t1 and t2).
Rotational speed would be how many times something rotated per unit of time. You would measure it in radians per second (rad/s) or revolutions per minute (rpm). You can refer to a rational kinetic energy calculator for more information on this topic.
You measure your average speed in distance per time. The formula looks like this:
average speed = total distance / total time
Common units for speed are kilometers per hour (kph), miles per hour (mph), feet per second (ft/s), and meters per second (m/s). In the speed calculator, the default is miles per hour, but you can change the unit to suit your needs.
The best thing about a speed calculator is how speedy it is. Once you enter your information, the result is instant. Follow these steps to work out your average speed.
1. Identify the distance you travel from A to B.
2. Enter the time it took to travel that distance.
3. Find out the average speed.
The speed calculator is straightforward to use, but you can also use the advanced mode. In this mode, you can compare differences in time if you traveled faster or slower. Such information could be helpful if you have spare time up your sleeve.
A common misconception exists that speed is the same as velocity. It is not. Speed tells you how fast something is moving. Velocity is a vector, which shows you the direction and the rate at which it changes.
An example would be if you ran 50 meters to a stop sign, then 50 meters back. You would be running in one position then another, but with a zero-average velocity. If you were calculating speed, you would provide an average per hour. If you were calculating velocity, it would also include the directional change.
Speed can be more than just how long it takes you to travel from point A to B. It can also relate to sound and how fast it is. Did you know the speed of light is around 300,000 kilometers per hour? If the light is traveling from the sun to the Earth, it will take eight minutes.
Sound moves at approximately 1234 kilometers per hour, or 343 meters per second. If there is a sound wave in the air, it needs a little under three seconds to travel one kilometer. To put it into perspective, remember the name, Felix Baumgartner?
In 2012, Felix broke the sound barrier during a freefall from 228,000 feet. He reached speeds of over 830 miles per hour! The average passenger jet cruising at 33,000 feet travels at 500 miles per hour.
While a cheetah is not as fast as Felix’s freefall, it’s still an incredible animal. A cheetah can run 58 miles per hour. An Atlantic sailfish can do even better, swimming at 68 miles per hour.
