Speed Today copy the words in red and underlined.

Speed Do you know how fast you can run? Do you know how fast you can ride your bike? Do you know how fast cars can drive on the street without getting a speeding ticket?

Speed Speed consists of two parts, distance and time.

Distance Distance can be measured in very short amounts, like millimeters (mm) or centimeters (cm) (or even inches) Distance can also be measured in large amounts, like meters (m) or kilometers (km) (or even miles)

Time Time can also be measured in very short amounts, like seconds (sec). Time can also be measured in longer amounts, like hours, months, years, even centuries!

Speed However, to calculate the speed of an object, it is only necessary to know Speed = distance time

Speed For example, Usain Bolt holds the Olympic record in the 100-meter dash at 9.63 seconds. How fast can he run? To calculate his speed, you take the formula Speed = and use 100 meters for the distance and 9.63 for the seconds. distance time

Speed Speed = So Speed = meters/second or m/s 100 meters 9.63 seconds

Speed Now it is your turn. The International Space Station travels 413,448 miles in 24 hours. What is its speed?

Speed First, what is the formula for speed? Speed = So speed = The answer is 17,227 miles/hour or 17,227mph. distance time 413,448 miles 24 hours

Speed Now let’s look at some distance-time graphs.

1.On a Distance-Time graph, when the line goes up or down, the object is moving. 2.When the line is flat, the object is NOT moving. 3.The steeper the line, the faster the object is moving.

1.How far did Mike ride at point C? (Hint: to find this, look at point C and then trace horizontally to the left side to find the distance.) 2.How far did Mike ride at point F?

3.What can you infer about Mike’s movement between points C, D, E, and F?

4.How far did Mike ride between points F and G? a.Hint: to find this, look at point G and then trace horizontally to the left side to find the distance. b.Then look at point F and then trace horizontally to the left side to find the distance. c.Next subtract the smaller number from the larger number. This is the total distance Mike rode. Answer: ____

5.How fast did Mike ride between points F and G? a.Hint: to find this, look at point G and then trace horizontally to the left side to find the distance. b.Then look at point F and then trace horizontally to the left side to find the distance. c.Next subtract the smaller number from the larger number. This is the total distance Mike rode. Answer: ____

5.How fast did Mike ride between points F and G? d.How long did Mike ride between points F and G? Hint: to find this, look at point G and then trace vertically to the left side to find the time. e.Then look at point F and then trace vertically to the left side to find the time. f.Next subtract the smaller number from the larger number. This is the total time Mike rode. Answer: _______

5.How fast did Mike ride between points F and G? g.Finally, to find the speed, use the formula Speed = distance/time using the distance from “c” and the time in “f”. Write your answer in above at #5.