Question

1. average speed and average velocity explain how average speed and average velocity are related to each other for an object in uniform motion.
2. position two cars are traveling along a straight road, as shown in figure 26. they pass each other at point b and then continue in opposite directions. the orange car travels for 0.25 h from point b to point c at a constant velocity of 32 km/h east. the blue car travels for 0.25 h from point b to point d at a constant velocity of 48 km/h west. how far has each car traveled from point b? what is the position of each car relative to the origin, point a?
3. position a car travels north along a straight highway at an average speed of 85 km/h. after driving 2.0 km the car passes a gas station and continues along the highway. what is the cars position relative to the start of its trip 0.25 h after it passes the gas station?
4. critical thinking in solving a physics problem, why is it important to create pictorial and physical models before trying to solve an equation?

Explanation:

In uniform motion, average speed is total distance over time (scalar), average velocity is total displacement over time (vector). Since direction is constant, displacement magnitude = distance, so average speed equals average velocity magnitude.

Step1: Calculate orange car distance from B

Distance = velocity × time = 32 km/h × 0.25 h = 8 km

Step2: Calculate blue car distance from B

Distance = 48 km/h × 0.25 h = 12 km

Step3: Orange car position relative to A

B is 6.0 km east of A; orange car is 8 km east of B: 6 + 8 = 14 km east

Step4: Blue car position relative to A

Blue car is 12 km west of B: 6 - 12 = -6 km (6 km west)

Step1: Distance after gas station

Distance = speed × time = 85 km/h × 0.25 h = 21.25 km

Step2: Total position from start

2.0 km + 21.25 km = 23.25 km north

Pictorial/physical models clarify variables, directions, and relationships, aiding in correct equation setup and reducing errors.

Answer:

Average speed is the magnitude of average velocity for an object in uniform motion, as displacement equals distance in constant direction.