Question

this graph shows the displacements and times for the winner of a horse race. what was the average speed of the horse that won the race? 0.05 m/s 20 m/s 45 m/s 285 m/s

Explanation:

Step1: Recall the formula for average speed

The formula for average speed \(v\) is \(v=\frac{\Delta x}{\Delta t}\), where \(\Delta x\) is the change in displacement and \(\Delta t\) is the change in time.

Step2: Identify \(\Delta x\) and \(\Delta t\) from the graph

From the graph, when \(t = 0\ s\), \(x=0\ m\) and when \(t = 15\ s\), \(x = 300\ m\). So, \(\Delta x=x_2 - x_1=300 - 0=300\ m\) and \(\Delta t=t_2 - t_1=15 - 0 = 15\ s\).

Step3: Calculate the average speed

Substitute the values into the formula: \(v=\frac{300}{15}=20\ m/s\)

Answer:

\(20\ m/s\) (the second option)