During an airplane's takeoff, its speed increases from to , and the work done by the net force during this process is . Then, its speed increases from to , and the work done by the net force during this second process is . What is the ratio of to ?
Options
A
1:1
B
1:3
C
3:5
D
4:9
Answer & Analysis
Answer
C
Analysis
To find the ratio of to , we can
use the work-energy theorem, which states that the work done by the net force
equals the change in kinetic energy:
For (speed increases from to
):
Thus,
For
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