My problem:
A swimmer travels from the south end to the north end of a 30.0 m pool in 15.0 s and makes the return trip to the starting position in 19.0 s. What is the average velocity for the second half of the swim?
My answer:
1.60 m/s to the south
Please check! I will really appreciate it. :)
Is this correct?
To find the average velocity for the second half of the swim, we need to calculate the swimmer's displacement during that time period. Displacement is the change in position from the starting point to the final point.
Given that the swimmer travels from the south end to the north end of a 30.0 m pool in 15.0 s, we know that the swimmer's initial position is at the south end and the final position is at the north end. Therefore, the swimmer's displacement during this time period is +30.0 m (positive indicates movement towards the north).
Next, we are told that the swimmer makes the return trip to the starting position in 19.0 s, which means that the swimmer travels from the north end back to the starting position (south end). Since the swimmer returns to the starting position, the displacement during this time period is 0 m.
Now, to find the displacement during the second half of the swim, we need to subtract the displacement of the return trip from the displacement of the initial trip.
Displacement during the second half = 0 m - 30.0 m = -30.0 m (negative indicates movement towards the south)
Finally, to find the average velocity, we divide the displacement during the second half by the time taken for the second half.
Average velocity for the second half = (-30.0 m) / (19.0 s) = -1.58 m/s
Therefore, the swimmer's average velocity for the second half of the swim is approximately -1.58 m/s to the south.
Note: It seems like there was a small rounding error in your answer. The correct answer is approximately -1.58 m/s.