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Top-fuel dragsters like the one shown above accelerate from rest at a tremendous rate. They race on a straight 1/4 mile long track. From a standing start, they complete the quarter mile in about 4.5 seconds and reach a speed of about 330 mph by the finish line.

Part A

Show that the statistics given in the problem introduction are inconsistent at the 10% level with the assumption that the dragster produces constant acceleration as it moves down the track.

System: Dragster as point particle.

Interactions: External influence from the ground (friction) assumed to produce constant acceleration.

Model: One-Dimensional Motion with Constant Acceleration.

Approach: We are asked to prove that the model we are examining does not fit the data. To do so, we look for a contradiction. In this case, we have several ways to find the acceleration, since we have a large number of givens. Choosing our coordinates such that the race begins at xi = 0 and proceeds in the positive x direction, we have:

Givens
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\begin

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[ t_

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= 0][t_

Unknown macro: {f}

=\mbox

Unknown macro: {4.5 s}

][ x_

= 0][x_

Unknown macro: {f}

= \mbox

Unknown macro: {402 m}

][v_

Unknown macro: {i}

= 0][v_

= \mbox

Unknown macro: {148 m/s}

]\end

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