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3 years ago

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A ball with mass m kg is thrown upward with initial velocity 28 m/s from the roof of a building 17 m high. Neglect air resistanc

e Use g = 9.8 m/s. Round your answers to one decimal place. (a) Find the maximum height above the ground that the ball reaches. meters (b) Assuming that the ball misses the building on the way down, find the time that it hits the ground. Fend Click If you would like to Show Work for this question: Open Show Work LINK TO TEXT

1 answer:

Nutka1998 [239]3 years ago

3 0

a. At its maximum height, the ball has zero vertical velocity, so

$-\left(28\dfrac{\rm m}{\rm s}\right)^2=2(-g)(y_{\rm max}-17\,\mathrm m)$

$\implies y_{\rm max}=57\,\mathrm m$

b. The ball's height in the air $y$ at time $t$ is given according to

$y=17\,\mathrm m+\left(28\dfrac{\rm m}{\rm s}\right)t-\dfrac g2t^2$

Solve for $t$ when $y=0$ :

$17+28t-4.9t^2=0\implies t\approx6.3\,\mathrm s$

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4 years ago

The simple interest on an investment of $8000 for one year is $360.

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4 years ago

If the inspection division of a county weights and measures department wants to estimate the mean amount of soft-drink fill in 2

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Answer:

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Step-by-step explanation:

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Assuming the X follows a normal distribution

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The next step would be find the value of $\z_{\alpha/2}$ , $\alpha=1-0.95=.05$ and $\alpha/2=0.025$

Using the normal standard table, excel or a calculator we see that:

$z_{\alpha/2}=1.96$

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$n=(\frac{z_{\alpha/2} \sigma}{Me})^2$

And we have everything to replace into the formula:

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4 years ago

Lady_Fox [76]

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3 years ago

Many residents of suburban neighborhoods own more than one car but consider one of their cars to be the main family vehicle. The

horrorfan [7]

Answer:

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Step-by-step explanation:

We are given the following information in the question:

Mean, μ = 2

Standard Deviation, σ = 6 months = 0.5 year

We are given that the distribution of age of cars is a bell shaped distribution that is a normal distribution.

Formula:

$z_{score} = \displaystyle\frac{x-\mu}{\sigma}$

P(family vehicles is between 1 and 3 years old)

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$P(1 \leq x \leq 3) = 95.4%$

95.4% of family vehicles is between 1 and 3 years old.

3 0

3 years ago