Book 5, Question 64 · Video
Wiggle Wiggle! Why Do Rivers Curve?
Water flows faster on the outside of a bend and wears away more of the bank there. On the inside of the bend, the water moves slower and drops sand and mud. Over time, these change
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What Crafty Clover says in this video
Intro
Hi! I'm Crafty Clover! Let's discover something amazing. Why do rivers curve?
The Big Idea
Look at a river from above. It hardly ever runs straight. It bends and winds like a snake! Water flows faster on the outside of a bend, and slower on the inside. So it eats away one side and drops sand on the other. Water takes the easy side, and then the bend grows!
Step 1
Step one: water hits a small bend. Rivers are never perfectly straight, because of rocks, roots, and lumps in the ground. Even a tiny wiggle is enough. The water swings toward one side.
Step 2
Step two: the outside wears away. On the outside of the bend, water flows faster. It digs into the bank and carries the soil away. The riverbank gets steeper and pushed back.
Step 3
Step three: the inside piles up sand. On the inside of the bend, the water is slow, so it drops the sand and pebbles it was carrying. The bend grows bigger and bigger over time.
A Closer Look
Let's look at a big curve, from above. The river is fast and strong on the outside. It's slow and gentle on the inside. Sometimes a bend gets so big that the river cuts across, leaving a curved lake called an oxbow.
Quick Facts
Quick facts! A winding river is called a meandering river. The word comes from a river in Turkey that has many bends. Rivers can move their bends slowly across the land over years and centuries. A river that flows on flat land tends to curve more than one that rushes down a steep mountain. Grown-up note: riverbanks can be soft and crumble. Stay back from the edge, and never swim in fast water.
Think Like a Scientist
Now, think like a scientist! Try this with a grown-up. Pour a slow stream of water down a slope of damp sand outside. Watch how the stream starts to bend. Where does the sand pile up?
Outro
So rivers curve because fast water digs one side, and slow water drops sand on the other. Amazing, right? Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!