Laws Of Motion Question 67
Question: Consider the following statement: When jumping from some height, you should bend your knees as you come to rest, instead of keeping your legs stiff. Which of the following relations can be useful in explaining the statement [AMU (Engg.) 2001]
Options:
A) $ \Delta \overrightarrow{P _{1}}=-\Delta \overrightarrow{P _{2}} $
B) $ \Delta E=-\Delta (PE+KE)=0 $
C) $ \overrightarrow{F}\Delta t=m\Delta \overrightarrow{v} $
D) $ \Delta \overrightarrow{x}\propto \Delta \overrightarrow{F} $ Where symbols have their usual meaning
Show Answer
Answer:
Correct Answer: C
Solution:
$ \overrightarrow{F}\Delta t=m\Delta \overrightarrow{v} $ therefore $ F=\frac{m\Delta \overrightarrow{v}}{t} $ By doing so time of change in momentum increases and impulsive force on knees decreases.
