Speed Distance and Time Speed is measured in

Speed, Distance and Time ü Speed is measured in metres per second (m/s) ü Therefore to work out speed we divide distance by time Speed = Distance Time ü You can use a triangle to help you with the following sums. D S X T Remember to put in your units! • Distance = 10 m, Time = 5 s What is the speed? • Distance = 100 m, Time = 10 s What is the speed? • Time = 20 s, Speed = 2 m/s What is the distance? • Distance = 500 m, Speed = 250 m/s What is the time? • A car travels at a speed of 10 m/s – how far does it travel in 10 seconds? • A person walks 240 m in 120 seconds. What is her speed? • An aeroplane takes 10 seconds to travel 2 km – what is its speed? (in m/s) Questions on Distance/Time Graphs 1. Draw a distance/time graph to show this motion of a car: A car starts at rest (not moving). It then travels 50 metres in 5 seconds. Then it stops for 2 seconds. It then travels 20 metres in 4 seconds. a) What is the speed of the car during the first 5 seconds? b) What is the total distance travelled by the car? c) What is the speed of the car in the last 4 seconds? 2. Draw a distance/time graph for this journey: Louise sets off on her bike from her house. She travels 100 m in 20 s. For the next 200 m she takes 30 s. She then stops for 30 s to have a sip of water. Then it starts to rain so she decides to go home. She takes 40 s to get back. a) Where is Louise’s speed the fastest? What is this speed? b) Where is Louise’s speed the slowest? What is this speed? b) What is the total distance travelled by Louise over her journey? c) How long did her journey take?