Comments on How can the kinetic energy equation be intuitively understood?
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How can the kinetic energy equation be intuitively understood?
Momentum is proportional to an object's velocity, and kinetic energy is proportional to the square of its velocity
Looking at braking seems to help. If you're going twice as fast when you start to brake and your speed linearly goes to zero, it will take you twice as long at constant deceleration to decelerate to zero, and the average speed while braking will be twice as great (half your initial speed). This implies that the braking distance is proportional to the square of your initial speed, so you're applying a braking force for four times the distance. Similarly, accelerating a car to 40 MPH will take 4 times as much distance as accelerating to 20 MPH. But that doesn't quite get me to energy.
I think there's just one more step to making the relationship to kinetic energy obvious, but I don't have it.
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Your analysis seems pretty good. To take an equivalent but more traditional example, imagine we throw a ball upwards. Ignoring air resistance and approximating the gravitational force as constant, the ball will accelerate downward with constant acceleration. If the initial (upwards) velocity is
Moving more towards your analysis, once we fix a constant force (and constant mass), then we know work is directly proportional to the distance,
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