Measuring Speed

#speed #force #motion #ngscience
ngscience.com
Measuring Speed is a short video explaining how we can describe and measure motion with specific reference to measuring speed in kilometres per hour and meters per second.
Describing Motion:
We know that something has moved when it has changed position. When something is in the process of changing position, we say it is in motion. We can describe and measure motion in different ways. We can describe motion in many ways. A bowling ball moves in a straight line towards the pins. On a swing you move back and forth. Think about the different things in a playground. How can you describe your motion when you play on different equipment?
On the seesaw, you move up and down. On a carousel, you move round and round. The skier moves in a zigzag pattern as he races down the mountain.
Measuring Motion:
Like describing the position of an object, we can use distance and direction to describe and measure motion.
An airplane travels about 2000 miles in an easterly direction to fly from San Francisco to Denver. You can also use time to describe motion. Time is how long it takes for something to move from one position to another. You can measure time using seconds, minutes and hours.
Compare the motion of the bicycle and the motorbike. How is the motion different?
The motorbike is moving much faster than the bicycle. How fast or slow something moves is its speed. We can measure speed by calculating the time it takes an object to cover a certain distance.
If a cyclist rides 30 kilometers in one hour, we can say the speed of the cyclist was 30 kilometers per hour.