Mahi Tuatahi ^🔗

Calculate and describe the velocity in each section of this distance-time graph. Time is in minutes.

Speed-Time Graphs ^🔗

• The gradient of a distance-time graph is the velocity
• The gradient of a speed-time graph is the acceleration
• The area under a speed-time graph is the distance travelled

Calculating Acceleration ^🔗

$$ \begin{aligned} a &= \frac{rise}{run} \cr a &= \frac{\Delta v}{\Delta t} \cr a &= \frac{v_{f} - v_{i}}{t_{f} - t_{i}} \end{aligned} $$

Pātai ^🔗

1. Calculate the acceleration for the positive acceleration section
2. Show, with maths, the acceleration is zero for the middle section
3. Calculate the acceleration for the negative acceleration section

Finding the Distance ^🔗

• Calculate the area under the speed-time graph to find the distance travelled
• Break it up into rectangles & triangles to calculate the area
• Finding area of a rectangle is $A = B \times H$
• On the graph $d = t \times v$
• This should look familiar from $v=\frac{d}{t} \rightarrow d = v \times t$!

Pātai ^🔗

1. Find the distance travelled in sections A, B and C
2. Find the total distance travelled
3. Describe the acceleration in each of A, B and C
4. Describe the velocity in each of A, B and C

Questions ^🔗

sciPAD Pages 18-21