Final answer:
The average speed of the object is 12 m/s, considering the total distance of 120 meters divided by 10 seconds. The average velocity is 8 m/s to the right, given by the net displacement of 80 meters (100 meters - 20 meters) divided by 10 seconds.
Step-by-step explanation:
The student has described the motion of an object that travels 100 meters to the right, turns around and travels 20 meters to the left, all within a time span of 10 seconds. To calculate the average speed and average velocity, we must consider the total distance traveled and the net displacement, respectively.
The total distance traveled is the sum of both segments of the trip: 100 meters to the right plus 20 meters back to the left, resulting in a total of 120 meters. The average speed is thus the total distance divided by the time:
Average Speed = Total Distance / Time = 120 m / 10 s = 12 m/s.
For the average velocity, we consider the net displacement, which is the overall change in position. The object ends up 80 meters to the right of the starting point (100 meters to the right minus 20 meters back to the left). Therefore, the average velocity is the net displacement divided by the time:
Average Velocity = Net Displacement / Time = 80 m / 10 s = 8 m/s to the right.
Thus, the correct answer is B) Average Speed: 12 m/s, Average Velocity: 8 m/s to the right.