A sky diver, with parachute unopened, falls 625 m in 15.0 s. Then she opens her parachute and falls another 348 m in 146 s. What is her average velocity (both magnitude and direction) for the entire fall?
Well, the direction of the average velocity should be considered down. No cross wind is mentioned, nor is the speed of the airplane when she jumps. (She would have had that horizontal velocity component initially.)
She falls a total distance of 625 + 338 m in a total time of 15 + 146 s. Do the addition required. The average speed is the ratio of thoue two numbers.
Then do the division.
To find the average velocity for the entire fall, we need to calculate the total displacement and divide it by the total time taken.
First, let's calculate the total displacement during the first phase of the fall, where the skydiver falls 625 m in 15.0 s. Since the direction is not specified, we'll assume downward as the positive direction. Therefore, the displacement during this phase is +625 m.
Next, we calculate the total displacement during the second phase of the fall, where the skydiver falls another 348 m in 146 s. Again, assuming downward as the positive direction, the displacement during this phase is also +348 m.
To find the total displacement, we add the individual displacements:
Total Displacement = 625 m + 348 m = 973 m
Now, let's calculate the total time taken for the entire fall:
Total Time = 15.0 s + 146 s = 161.0 s
Finally, to find the average velocity, we divide the total displacement by the total time:
Average Velocity = Total Displacement / Total Time
Average Velocity = 973 m / 161.0 s
Average Velocity ≈ 6.04 m/s
The magnitude of the average velocity is approximately 6.04 m/s, but since both the displacements were in the downward direction, the direction of the average velocity is also downward.
To find the average velocity for the entire fall, we need to calculate the total displacement and the total time.
First, let's find the total displacement. The skydiver falls 625 m in 15.0 s and then falls an additional 348 m. So the total displacement is 625 m + 348 m = 973 m.
Next, let's find the total time. The skydiver falls for 15.0 s initially and then falls an additional 146 s. So the total time is 15.0 s + 146 s = 161 s.
Now we can calculate the average velocity by dividing the total displacement by the total time.
Average velocity = Total displacement / Total time
Average velocity = 973 m / 161 s
Calculating this, we get an average velocity of approximately 6.04 m/s.
Therefore, the average velocity of the skydiver's entire fall is 6.04 m/s downwards.