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Learning how to change which way an object is going.
Imagine you are playing soccer. You kick the ball toward the goal, but a friend kicks it from the side! Where does the ball go now?
When an object is already moving, it likes to go in a straight line. But what if you want it to go somewhere else? You can give it a push from the side! A push from the side does not stop the object. Instead, it makes the object turn. This is called changing direction. Think of a toy car rolling on the floor. If you poke the side of the car while it moves, it will veer off to a new path.
1. Roll a ball straight ahead of you. 2. While it is moving, use your hand to gently tap the side of the ball time. 3. Watch as the ball stops going straight and moves toward the side you pushed it!
Quick Check
If a ball is rolling away from you and you push it from the left side, which way will it turn?
Answer
It will turn toward the right.
A curve is a path that is not straight. It looks like a part of a circle or a rainbow. To make a ball move in a curve, you have to keep pushing it! If you give a moving ball many tiny pushes from the same side, it will keep turning. Instead of a sharp corner, it makes a smooth, rounded curved path. You can also make a curve by rolling a ball across a slanted surface, like a ramp tilted to one side.
1. Find a large bowl or a hula hoop. 2. Roll a marble along the inside edge. 3. The wall of the bowl pushes the marble times every second, forcing it to move in a curve instead of a straight line.
Quick Check
What do we call a path that looks like a circle or a bend?
Answer
A curved path (or a curve).
To be a science expert, you need to describe how things move. We use special words to do this. Left and Right tell us which side the object turned toward. Up and Down tell us if it moved toward the sky or the ground. If you are steering a bike, you pull the handlebars left to go that way. If you throw a ball into the air, it goes up first, then it changes direction and comes back down.
1. Place two cups on the floor feet apart. 2. Try to roll a ball so it goes right around the first cup. 3. Then, use a quick push to make it turn left to go around the second cup. 4. You just changed the direction times!
What happens when you push a moving toy car from the side?
Which word describes a path that bends like a rainbow?
You can use a push to make a ball go left or right.
Review Tomorrow
Tomorrow, look at a car turning a corner and try to remember: was it a push from the side that made it turn?
Practice Activity
Set up a 'goal' using two shoes. Try to roll a ball from the side and use one hand to 'steer' it into the goal using only side pushes!