(18+4)+m=(5-3)m

An object at the top of a building with height 110 feet is thrown upward with an initial speed of 23 ft/s. Find its position z(t

alina1380 [7]

Answer:

Step-by-step explanation:

Given

Height of building is $h=110\ ft$

Initial upward velocity $u=23\ ft/s$

height of object is given by

$z(t)=ut+\frac{1}{2}gt^2$

but building is already at a height of 110 ft so z(t) must be given by

$Z(t)=ut+\frac{1}{2}(-g)t^2+110$

$Z(t)=23\times t-\frac{1}{2}\times 9.8\times t^2$

$Z(t)=-16t^2+23t+110$

Time when it hits is given by when Z(t)=0[/tex]

$-16t^2+23t+110=0$

$t=\frac{-23\pm \sqrt{(23)^2-4\times (-16)\times 110}}{2\times (-16)}$

$t=\frac{-23\pm 87}{-32}$

$t=3.43\ s$

6 0

3 years ago

An observer on a cliff 1000 yards above sea level sights two ships due east. The angles of depression from the observers perspec

Anika [276]

Answer:

480.53 yards

Step-by-step explanation:

cos(35) = 1000/hypotenuse1 - multiply by h (hypotenuse)

(h1)cos(35) = 1000 - divide by cos(35)

h1 = 1000 / cos(35)

h1 = 1220.7746

Same thing with the angle of depression of 54 degrees.

h2 = 1000 / cos(54)

h2 = 1701.3016

h2 - h1 = 480.53

3 0

2 years ago

Use the divergence theorem to find the outward flux of the vector field F(xyz)= 4x^2 i + 4y^2 j + 3z^2 k across the boundary of

Pavel [41]

$\vec F(x,y,z)=4x^2\,\vec\imath+4y^2\,\vec\jmath+3z^2\,\vec k\implies\nabla\cdot\vec F=8x+8y+6z$

Let $S$ be the surface of the rectangular prism bounded by the planes $x=0$ , $x=a$ , $y=0$ , $y=b$ , $z=0$ , and $z=c$ . By the divergence theorem, the integral of $\vec F$ over $S$ is given by the integral of $\nabla\cdot\vec F$ over the interior of $S$ (call it $R$ ):

$\displaystyle\iint_S\vec F\cdot\mathrm d\vec S=\iiint_R(\nabla\cdot\vec F)\,\mathrm dV$

$=\displaystyle\int_0^c\int_0^b\int_0^a(8x+8y+6z)\,\mathrm dx\,\mathrm dy\,\mathrm dz=\boxed{abc(4a+4b+3c)}$

5 0

3 years ago

Determine the critical value or values for a one-mean z-test at the 1% significance level if the hypothesis test is right-tailed

kifflom [539]

Answer:

We need to conduct a hypothesis in order to determine if the mean is greater than specified value, the system of hypothesis would be:

Null hypothesis: $\mu \leq \mu_o$

Alternative hypothesis: $\mu > \mu_o$

For this case the significance is 1%. So we need to find a critical value in the normal standard distribution who accumulates 0.99 of the area in the left and 0.01 in the right and for this case this critical value is:

$z_{crit}= 2.326$

Step-by-step explanation:

Notation

$\bar X$ represent the sample mean

$\sigma$ represent the standard deviation for the population

$n=$ sample size

$\mu_o$ represent the value that we want to test

$\alpha$ represent the significance level for the hypothesis test.

z would represent the statistic (variable of interest)

State the null and alternative hypotheses.

We need to conduct a hypothesis in order to determine if the mean is greater than specified value, the system of hypothesis would be:

Null hypothesis: $\mu \leq \mu_o$

Alternative hypothesis: $\mu > \mu_o$

For this case the significance is 1%. So we need to find a critical value in the normal standard distribution who accumulates 0.99 of the area in the left and 0.01 in the right and for this case this critical value is:

$z_{crit}= 2.326$

3 0

2 years ago

2/3 times x = 4/9 <br> Solve for X<br> 10 points

BabaBlast [244]

Answer:

The answer is 2/3

Step-by-step explanation:

Let's solve your equation step-by-step.

2/ 3(x)=4/9

Step 1: Multiply both sides by 3/2.

( 3/2)*(2/3*x)=(3/2)*(4/9)

so this means the answer is 2/3

6 0

3 years ago