Distance

Distance measures how long the path that we travelled was.

It’s not in any specific direction, so it’s a scalar quantity.

Example

• Let’s suppose we walk 1km north, then 2km back.
• The total distance we travelled is 3km, because that’s the length of the path of the journey that we walked.

\text{distance}=\text{speed}\times\text{time}

s=vt

Where:

• s is the distance, measured in metres, m
• v is the speed, measured in metres per second, ms^{-1} (m/s)
• t is the time, measured in seconds, s

A van drives at a speed of 20ms^{-1} for 10s. Calculate the distance.

• s=vt
• s=20\times10=200
• Answer: 200m

A car drives at a speed of 15ms^{-1} for 5s. Calculate the distance.

• s=vt
• s=15\times5=75
• Answer: 75m

A bike drives at a speed of 0.5ms^{-1} for 20s. Calculate the distance.

• s=vt
• s=0.5\times20=10
• Answer: 10m

A truck drives at a speed of 30ms^{-1} for 8s. Calculate the distance.

• s=vt
• s=30\times8=240- Answer: 240m

A car drives at a speed of 25ms^{-1} for 12s. Calculate the distance.

• s=vt
• s=25\times12=300
• Answer: 300m

A van drives at a speed of 40ms^{-1} for 15s. Calculate the distance.

• s=vt
• s=40\times15=600
• Answer: 600m

A person cycles for 4h until reaching a destination 100km away. Calculate their average speed.

• s=vt
• v=\frac st
• v=\frac{100}{4}=25
• Answer: 25kmh^{-1}