what is speed? all the runners in the one kilometer race will start at exactly the same time. they...

What Is Speed?What Is Speed?

All the runners in the one kilometer race will start at exactly the same time. They will all go exactly the same distance. One runner will reach the finish line before the others. The winning runner has the fastest speed. All moving objects have speed. Speed is the distance an object moves in a certain amount of time.

The winner of this race will be the runner with the fastest speed. He will cover the same distance as the other runners but will finish in the shortest time.

You can measure the speed of an object if you know two things about its motion: first, how far the object traveled; second, how long it took to go that distance. With these two measurements, you can figure out an object’s speed. To calculate speed, divide the distance traveled by the time spent moving.

If a car goes 50 miles in 1 hour, its speed is 50 miles per hour. If you walk 10 kilometers in 2 hours, your speed is 5 kilometers per hour.

Objects in motion often change their speed. They can speed up or slow down. They can also change their direction. Any change in the speed or direction of a moving object is called acceleration

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Main Idea and DetailsMain Idea and Details

• In one word, what is the topic of this passage?

• What is the main idea of this passage?

• What is one supporting detail about this main idea?

How do you calculate speed?How do you calculate speed?

• Answer the question…– With a partner– In your Learning Notebook

speedspeed

• Speed is the distance an object moves in a certain amount of time.

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