Last week we talked about the 3 main factors that affect the motion of an object. Can you remember what they are? They are position, direction, and speed. I do not know about you, but when it comes to directions I have a hard time finding my way around. Luckily for me we now have things like GPS to help me find my way. However, did you know that was not always the case? Before we had GPS people would use the stars, sun, moon, and something called a compass to help them navigate. A compass is an instrument containing a magnetized pointer that shows the direction of magnetic north.
Did you know that there are three main factors that affect the motion of an object? They are position, direction, and speed. I’m sure you have all seen the speed limits that are along the side of the roads. Those signs are in miles per hour. However, you may not know that there is a different measurement used throughout our waterways. The difference is that they use the term nautical mile. The term nautical mile comes from long ago when sailors would let a rope with knots tided in it drag behind the boat for a set period of time. When that time was up they would simply count the knots to see how fast they were going. Today, a nautical mile represents a distance slightly longer than a mile.
There are many types of landforms that make up our worlds ecosystems. A type of landform that we have all heard of is a valley. Valleys can be defined as an area of lowland between ranges of hills or mountains. A recent discovery in a valley in China has given scientists a new idea on how dinosaurs might have looked. They found a dinosaur tail encased in amber that was covered in feathers. Scientists are now beginning to think that many of our dinosaur friends were covered with feathers!
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