Question

Tommy was walking at a rate of 4 miles/hour at noon and at 12:30 pm he was walking at a brisk rate of 6 miles/hour. Two hours later Tommy was walking at a leisurely rate of 2 miles/hour. Which statement about Tommy's acceleration is true?

1) Tommy's acceleration is constant throughout the entire time period.
2) Tommy's acceleration is increasing as time progresses.
3) Tommy's acceleration is decreasing as time progresses.
4) Cannot be determined based on the given information.

Answer 1

Tommy's acceleration changes as he adjusts his speed, meaning it is not constant. Without specific rates of speed change, we cannot determine if the acceleration is consistently increasing or decreasing.

Step-by-step explanation:

Tommy's acceleration is not constant throughout the entire time period. At noon, Tommy starts walking at a rate of 4 miles/hour and then increases his speed to 6 miles/hour at 12:30 pm. This change in velocity over half an hour means Tommy has accelerated. Two hours later, Tommy decreases his speed to 2 miles/hour, indicating deceleration, or negative acceleration. Since the rate of velocity change is not the same throughout the period observed, Tommy's acceleration is neither constant nor can we infer a consistent pattern of increasing or decreasing acceleration without specific numerical values for how quickly these changes in speed occurred.