Question

1. brad, brittany and matt competed in a triathlon relay. brad swam 4 km in 30 minutes, brittany biked 180 km in 6.5 hours, and matt ran 42 km in 3 hours. what was their average speed for the total triathlon? given: formula: substitute: answer: 16. give an example for instantaneous speed. 17. what is the difference between speed and velocity? 18. why cant you have a vertical line on a speed distance graph?

Explanation:

Question 15

Step1: Convert time to hours

Brad's time: $30\ \text{minutes} = \frac{30}{60} = 0.5\ \text{hours}$

Step2: Calculate total distance

$\text{Total Distance} = 4 + 180 + 42 = 226\ \text{km}$

Step3: Calculate total time

$\text{Total Time} = 0.5 + 6.5 + 3 = 10\ \text{hours}$

Step4: Apply average speed formula

Average speed = $\frac{\text{Total Distance}}{\text{Total Time}}$
$\text{Average Speed} = \frac{226}{10}$

Instantaneous speed is the speed of an object at a specific moment in time. It measures how fast the object is moving exactly at that instant, not over a period.

The key distinction lies in direction: speed is a scalar quantity, only measuring how fast an object moves, while velocity is a vector quantity that includes both the speed of the object and its direction of motion.

Answer:

$22.6\ \text{km/h}$

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Question 16