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vova2212 [387]
3 years ago
15

The height h, in feet of a model rocket t seconds after launch is given

Mathematics
1 answer:
Illusion [34]3 years ago
7 0

Answer:

h_max = 324.09 ft

Step-by-step explanation:

The correct equation is;

h = 245t - 16t²

We are told that as the rocket descends, it deploys

a recovery parachute when it reaches 325 feet above the ground.

Thus;

245t - 16t² = 325

Thus;

16t² - 245t + 325 = 0

Using quadratic formula, we have the roots as;

t = 1.47s or 13.85s

We will pick the higher value.

Thus;

Maximum height will occur at t = 13.85 s

Thus, plugging in 13.85 for t into h = 245t - 16t², we have;

h_max = 245(13.85) - 16(13.85)²

h_max = 324.09 ft

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nika2105 [10]

Answer:

a) X ~ exp ( 10 )

b) E(X) = 0.1 , Var (X) = 0.01

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Step-by-step explanation:

Solution:-

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- Denote a random variable "X"represent a single interspike interval (ISI) having an exponential distribution.

- Where X follows exponential distribution defined by event rate parameter i.e λ.

                               X ~ Exp ( λ )

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                               X ~ Exp ( 10 )

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                               E(X) = 0.1 s per neuron.

- The variance is the variation in the time taken by a single neuron to be emitted. It is defined as:

                               Var (X) = 1 / λ^2

                               Var (X) = 1 / 10^2

                               Var (X) = 0.01 s^2

- The probability that ISI is less than t = 0.07 seconds: P ( X < t = 0.07 s):

- The cumulative distribution function for exponential variate "X" is:

                                P ( X < t ) = 1 - e^(-λ*t)

- Plug the values and the determine:

                                P ( X < 0.07 ) = 1 - e^(-0.1*0.07)

                                                      = 1 - 0.99302

                                                      = 0.00698

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