Displacement
Displacement measures how far we are from our starting position.
Importantly, we measure it in a certain direction, so it’s a vector quantity
Example
- Let’s suppose we walk 1km north, then 2km back.
- The total distance we travelled is 3km.
- But our displacement is 1km south: because that’s how much our current position has changed.
\text{displacement}=\text{velocity}\times\text{time}
Where:
s is the displacement, measured in metres,m v is the velocity, measured in metres per second,ms^{-1} (m/s )t is the time, measured in seconds,s
A lorry travels at a velocity of 20ms^{-1} for 10s. Calculate the displacement.
s=vt s=20\times10=200 - Answer:
200m
A car travels at a velocity of 15ms^{-1} for 5s. Calculate the displacement.
s=vt s=15\times5=75 - Answer:
75m
A bike travels at a velocity of 0.5ms^{-1} for 20s. Calculate the displacement.
s=vt s=0.5\times20=10 - Answer:
10m
A car travels at a velocity of 30ms^{-1} for 8s. Calculatethe displacement.
s=vt s=30\times8=240 - Answer:240m
A lorry travels at a velocity of 25ms^{-1} for 12s. Calculate the displacement.
s=vt s=25\times12=300 - Answer:
300m
flashcards
| Question | Answer |
|---|---|
| What is displacement? | Displacement measures how far we are from our starting position, in a certain direction. It is a vector quantity. |
| If you walk 1km north then 2km back, what is the total distance travelled and what is the displacement? | Total distance is 3km. Displacement is 1km south. |
| What is the formula linking displacement, velocity, and time? | |
| A lorry travels at | |
| A car travels at | |
| A bike travels at | |
| A car travels at | |
| A lorry travels at |