Speed, Distance & Time Speed = Distance Time Time = Distance Speed

Distance = Speed x Time

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Speed Practice Problems A family takes a car trip heading

northeast from Durham, NC to Washington, DC. They travel for 4 hours and cover 360 km. What was their average speed?

Speed = Distance

Time

= 360 km 4 h

= 90 km/h

Speed vs. Velocity

SPEED – tells you have fast or slow something is moving (changing position). Example = 25 km/h

VELOCITY – tells you speed AND DIRECTION! (changing position in a certain direction) Example = 25 km/h EAST

Speed Practice Problems A family takes a car trip heading

northeast from Durham, NC to Washington, DC. Their speed was 90 km/h. What was their VELOCITY?

Velocity is SPEED and DIRECTION!

Velocity = 90 km/h NORTHEAST

Speed Practice Problems After school, Mrs. Duncan went for a jog along Cornwallis Rd. She ran for 30 minutes at a speed of 150 m/min. How far did she run?

Distance = Speed x Time

Distance = 150 m/min x 30 min

Distance = 4500 meters (4.5 km)

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Speed Practice Problems Mr. Walsh goes on a long bike ride in the country. He rides his bike 35 km at a speed of 20 km/h. For how long was he riding his bike?

Time = Distance Speed

Time = 35 km 20 km/h

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= 1.75 h

Acceleration Practice Problems Ms. Lewis buys a new car that can

accelerate from rest (0 m/s) to 24 m/s in 8 seconds. What is the car’s rate of acceleration?

Acceleration = Final speed – Initial Speed Time

Acceleration = 24 m/s – 0 m/s 8 s

= 3 m/s2

What was the average speed of the runner in the first 5

seconds of the race?

Speed = 25 m 5 s

Speed = 5 m/s

A snail slowly slithers down the sidewalk. It travels at a speed of 3 cm/min. How far would it travel in 20 minutes? Distance = Speed x Time

Distance = 3 cm/min x 20 min

Distance = 60 cm

The fastest man on earth, Usain Bolt, runs at a speed of 10 m/s. How long would it take him to run 160 meters? Time = Distance Speed Time = 160 m 10 m/s Time = 16 seconds!