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adelina 88 [10]

2 years ago

10

A car is traveling with a constant speed when the driver suddenly applies the brakes, giving the 14) car a deceleration of 3.50

m/s2. if the car comes to a stop in a distance of 30.0 m, what was the car's original speed?

1 answer:

sergij07 [2.7K]2 years ago

7 0

To be able to determine the original speed of the car, we use kinematic equations to relate the acceleration, distance and the original speed of the car moving.

First, we manipulate the one of the kinematic equations

v^2 = v0^2 + 2 (a) (x) where v = 0 since the car stopped

Writing the equation in such a way that the initial velocity or v0 is written on one side of the equation,

<span>we get v0 = sqrt (2(a)(x))

Substituting the known values,

v0 = sqrt(2(3.50)(30.0))
v0 = 14.49 m/s
</span>
Therefore, before stopping the car the original speed of the car would be 14.49 m/s

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Answer:

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A particle in the first excited state of a one-dimensional infinite potential energy well (with U = 0 inside the well) has an en

nataly862011 [7]

Answer:

The energy of this particle in the ground state is E₁=1.5 eV.

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In the ground state (n=1). In the first excited state (n=2) we are told the energy is E₂= 6.0 eV. If we replace in the above equation we get that:

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Answer:

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2 years ago