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At a drag race, a jet car travels 0.25 mile in 5.2 seconds. What is the car's final speed (m/s) and acceleration (m/s²)?

A) Final speed = 48.08 m/s, Acceleration = 9.8 m/s²
B) Final speed = 9.8 m/s, Acceleration = 48.08 m/s²
C) Final speed = 12.5 m/s, Acceleration = 0.052 m/s²
D) Final speed = 0.052 m/s, Acceleration = 12.5 m/s²

1 Answer

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Final answer:

The final speed of the jet car is approximately 98 m/s, and the acceleration is approximately 18.843 m/s² when it travels 0.25 mile in 5.2 seconds.

Step-by-step explanation:

To determine the jet car's final speed and acceleration, we need to convert the distance from miles to meters and then use the kinematic equations for uniformly accelerated motion. A quarter mile is equivalent to 402.336 meters (1 mile = 1609.34 meters). Assuming the car starts from rest and accelerates evenly, we can use the equation:

v = u + at,

where v is the final velocity, u is the initial velocity (0 m/s since it starts from rest), a is the acceleration, and t is the time (5.2 seconds). Since the car starts from rest, the equation simplifies to v = at. Next, we use the distance equation:

s = ut + (0.5)at2,

where s is the distance (402.336 meters), which again simplifies to s = (0.5)at2 since u=0. By rearranging to solve for a, we have:

a = (2s)/t2 = (2 * 402.336)/(5.2)2 ≈ 18.843 m/s2.

Now we can find v using a and t:

v = at = 18.843 * 5.2 ≈ 98 m/s.

Therefore, the final speed of the jet car is approximately 98 m/s, and the acceleration is approximately 18.843 m/s2.

User Roman Yakoviv
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