Larry leaves home at 9:03 and runs at constant speed to the lamppost(200 yards from the start). He reaches the lamppost at 9:07, immediately turns, and runs to the tree(1200 yards from the start). Larry arrives at the tree at 9:13.
What is Larry’s average velocity, in yards/min, during each of these two intervals.
Express your answer using three significant figures.
I got 50.0 y/m and 167 y/m
I can say noting about velocity because all I have is speed. For velocity direction is also required.
For speed you can use a speedometer.
For velocity you need both a speedometer and a compass.
1) 8
2) 5
To calculate Larry's average velocity, we need to use the formula:
Average Velocity = Total Distance / Total Time
First, let's calculate the total distance and total time for the first interval from the start to the lamppost.
Distance from the start to the lamppost = 200 yards
Time taken from the start to the lamppost = 9:07 - 9:03 = 4 minutes
Total Distance for the first interval = 200 yards
Total Time for the first interval = 4 minutes
Average Velocity for the first interval = Total Distance / Total Time
= 200 yards / 4 minutes
= 50.0 yards/minute
Hence, your calculation for the average velocity during the first interval is correct at 50.0 y/m.
Now, let's calculate the total distance and total time for the second interval from the lamppost to the tree.
Distance from the lamppost to the tree = 1200 yards
Time taken from the lamppost to the tree = 9:13 - 9:07 = 6 minutes
Total Distance for the second interval = 1200 yards
Total Time for the second interval = 6 minutes
Average Velocity for the second interval = Total Distance / Total Time
= 1200 yards / 6 minutes
= 200 yards/minute
Hence, the correct calculation for the average velocity during the second interval is 200 y/m, not 167 y/m.
To summarize:
Average velocity during the first interval (start to lamppost) = 50.0 y/m
Average velocity during the second interval (lamppost to tree) = 200 y/m
To find Larry's average velocity during each interval, we need to divide the distance covered in each interval by the time taken in each interval.
First, let's calculate the time taken for the first interval:
Larry leaves home at 9:03 and reaches the lamppost at 9:07, so the time taken is 4 minutes.
The distance covered in the first interval is 200 yards.
Average velocity = Distance / Time = 200 yards / 4 minutes = 50 yards/minute
So, Larry's average velocity during the first interval is 50 yards/minute.
Next, let's calculate the time taken for the second interval:
Larry reaches the lamppost at 9:07 and arrives at the tree at 9:13, so the time taken is 6 minutes.
The distance covered in the second interval is 1200 yards.
Average velocity = Distance / Time = 1200 yards / 6 minutes = 200 yards/minute
So, Larry's average velocity during the second interval is 200 yards/minute.
Therefore, Larry's average velocity during each of these two intervals is 50.0 y/m and 200 y/m, respectfully, as rounded to three significant figures.
Note: It seems like there was a typo in your question, as you mentioned 167 y/m for the second interval. However, the correct result, using the given values, is actually 200 y/m.