Explaining MotionDistance Time Graphs

Learning TweetTo understand how to plot and read Distance-Time

GraphsTo understand the relationship between velocity and

distance time graphs

Measuring DistanceMetre – international unit for measuring distance.

= 50 m1 mm

Calculating SpeedSpeed (S) = distance traveled (d) / the amount of time it

took (t).

S = d/t

Calculating speedIf I travel 100 kilometre in one hour then I have a speed

of…100 km/h

If I travel 1 metre in 1 second then I have a speed of….1 m/s

S = d/t

Calculating Average Speed It took 1 hour to go 40 km on the motorway. Then it took

me 2 more hours to go 20 km using the streets.Total Distance: 40 km + 20 km = 60 kmTotal Time: 1 h + 2 h = 3 hrAve. Speed:

total dist/total time = 60 km/3 h = 20 km/h timeTotal

DistTotalSpeedAve

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timeTotal

DistTotalSpeedAve

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Distance Time

VelocityVelocity – the SPEED and DIRECTION of an object.

Example: An plane moving North at 500 mph A missile moving towards you at 200 m/s

Learning TweetMomentum

Know that Momentum is mass (kg) x Velocity (m/s)Explain a force acting for a certain time causes a change

in momentum

Velocity – Speed

Velocity –time graph Slope = acceleration

A-B= steady accelerationB= steady speed

C= steady de-cceleration