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3 years ago

7

A Lua reflete parte da luz solar que nela incide. Admite que: a luz refletida pela Lua demora 1,28 segundos a chegar à Terra; en

tre a Lua e a Terra, a luz percorre 300 000 000 de metros em cada segundo; o trajeto da luz é retilíneo. Determina a distância da Lua à Terra. Apresenta o resultado em metros, escrito em notação científica. Mostra como chegaste à tua resposta.

1 answer:

Anuta_ua [19.1K]3 years ago

4 0

Answer:

3.84 * 10^8 meters

Step-by-step explanation:

As the speed of light is 300,000,000 meters/second and the time that the light takes to go from the moon to the Earth is 1.28 seconds, we can find the distance using the formula:

Distance = speed * time

So we have that:

Distance = 300,000,000 * 1.28 = 384,000,000 meters

In cientific notation, we need the first number to be in the interval from 1 to 10, so we have 3.84, and we have to multiply by 10^8 to reach our result, so we have:

Distance = 3.84 * 10^8 meters

You might be interested in

F(x)=25x^2-10x+1 what is the the value of the discriminant of f

Elanso [62]

Answer:

0

Step-by-step explanation:

Quadratic equation

$x=\frac{-b+-\sqrt{b^{2}-4*a*c} }{2*a}$

The discriminant is the part of the quadratic formula within the square root symbol: ${b^{2}-4*a*c}$ . The discriminant indicates if there are two solutions, one solution, or none.

The discriminant can be positive, zero or negative which determines how roots exist for the given quadratic equation.

So, a positive discriminant tell us that the quadratic has two different real solutions.

A discriminant of zero tell us that the quadratic has two real and equal solutions.

And a negative discriminant tell us that none of the solutions are real numbers.

In this case: 25x^2-10x+1=0

We can see that

a= 25 b=-10 c=1

Using: ${b^{2}-4*a*c}$

We have $-10^{2}-4* 25*1 =100-100=0$

the answer is zero, so the quadratic has two real and equal solutions

7 0

3 years ago

10x+2=9x3<br> what is the answer

yKpoI14uk [10]

Answer:

8.5

Step-by-step explanation:

10x+2=9x(3)

10x+2=27x

2=17x

x=8.5

6 0

3 years ago

En la tienda de mascotas "Animalo-T", se desea elevar un elefante de 2,900 kg utilizando una elevadora hidráulica de plato grand

Korvikt [17]

Answer:

Se requiere una fuerza de 854.473 newtons sobre el émbolo pequeño.

Step-by-step explanation:

Por el Principio de Pascal se conoce que el esfuerzo experimentado por el elefante es igual a la presión ejercida por el plato pequeño. Es decir:

$\frac{F_{1}}{A_{1}} = \frac{F_{2}}{A_{2}}$ (1)

Donde:

$F_{1}$ - Fuerza experimentada por el elefante, medida en newtons.

$F_{2}$ - Fuerza aplicada sobre el plato pequeño, medida en newtons.

$A_{1}$ - Área del plato grande, medida en metros cuadrados.

$A_{2}$ - Área del plato pequeño, medida en metros cuadrados.

La fuerza aplicada sobre el plato pequeño es:

$F_{2} = \left(\frac{A_{2}}{A_{1}} \right)\cdot F_{1}$

La fuerza experimentada por el elefante es su propio peso. Por otra parte, el área del plato es directamente proporcional al cuadrado de su diámetro. Es decir:

$F_{2} = \left(\frac{D_{2}}{D_{1}} \right)^{2}\cdot m\cdot g$ (2)

Donde:

$D_{1}$ - Diámetro del plato grande, medido en centímetros.

$D_{2}$ - Diámetro del plato pequeño, medido en centímetros.

$m$ - Masa del elefante, medida en kilogramos.

$g$ - Aceleración gravitacional, medida en metros por segundo cuadrado.

Si sabemos que $D_{1} = 0.75\,m$ , $D_{2} = 0.13\,m$ , $m = 2900\,kg$ y $g = 9.807\,\frac{m}{s^{2}}$ , entonces la fuerza a aplicar al émbolo pequeño es:

$F_{2} = \left(\frac{0.13\,m}{0.75\,m} \right)^{2}\cdot (2900\,kg)\cdot \left(9.807\,\frac{m}{s^{2}} \right)$

$F_{2} = 854.473\,N$

Se requiere una fuerza de 854.473 newtons sobre el émbolo pequeño.

3 0

3 years ago

A mermaid is swimming at sea level when a human comes by. She dives underwater at a rate of 8 meters per second. She continues t

Kay [80]

She will be at 160 meters

4 0

3 years ago

Please help and explain!

Scrat [10]

K is the slope of the line formed by connecting the points.
Use slope formula:
$\frac{y_2 - y_1}{x_2 - x_1}$
where the 2 points are the end points of the line (First and last going Left to right)
$(x_1,y_1) = (2,7) \\ (x_2,y_2) = (8,28)$
Substitute into slope formula
$k= \frac{28-7}{8-2} = \frac{21}{6} = \frac{7}{2}$
You can check if this is correct by going back to graph and going "up 7" and "over 2" to get from one point to the next.

5 0

3 years ago