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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, where symbols have their usual meanings. ∆p₁ = -∆p₂ ∆E = -∆PE + KE = 0 F ∆t = m∆v ∆v ⋉ ⋉F

User Rich Walsh
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Final answer:

The Physics concept of change in momentum can explain why bending your knees when jumping from a height reduces impact force. Bending the knees increases the time over which momentum change occurs, thus reducing the force exerted on the body due to Newton's second law.

Step-by-step explanation:

The subject matter related to this question is Physics as the student is asking about a kinematic event related to jumping from some height. In Physics, when one jumps from a certain height and lands by bending their knees, the time over which the change in momentum (∆p) is taking place is increased. This is represented by the relation F ∆t = m∆v. Here, F is the force, t is time, m is mass, and v is velocity.

When you bend your knees, the force exerted over your body due to the stop in momentum is spread out over a longer duration, thus reducing the impact force. This is why it's less jarring and generally safer to bend your knees as you land. The change in momentum is absorbed over a larger time, resulting in a smaller force exerted on your body due to Newton's second law of motion. This reduces the potential harm caused by the sudden deceleration when landing.

Learn more about Force & momentum

User Jade Ellis
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