What other issues, besides addiction, might go along with overuse of phones?

On average, how many stars would we have to search before we would expect to hear a signal? assume there are 500 billion stars i

Keith_Richards [23]

We would have to search at least 5,000,000,000 (5 billion) stars before we would expect to hear a signal.

To find out the number of stars that we will need to search to find a signal, we need to use the following formula:

total of stars/civilizations
500,000,000,000 (500 billion) stars / 100 civilization = 5,000,000,000 (5 billion)

This shows it is expected to find a civilization every 5 billion stars, and therefore it is necessary to search at least 5 billion stars before hearing a signal from any civilization.

Note: This question is incomplete; here is the complete question.

On average, how many stars would we have to search before we would expect to hear a signal? Assume there are 500 billion stars in the galaxy.

Assuming 100 civilizations existed.

Learn more about stars in: brainly.com/question/2166533

7 0

3 years ago

A child in danger of drowning in a river is being carried downstream by a current that flows due south uniformly with a speed of

tia_tia [17]

Let the rescue boat starts at an angle theta with the North

now its velocity towards East is given as

$v_x = 24sin\theta$

$v_y = -24cos\theta + 3$

now in some time "t" it will catch the boy

so we will have

$t = \frac{0.5}{24sin\theta}$

also we have

$t = \frac{2}{-24cos\theta + 3}$

now we have

$\frac{2}{-24cos\theta + 3} = \frac{0.5}{24sin\theta}$

$4*24sin\theta = - 24cos\theta + 3$

$96 sin\theta + 24cos\theta = 3$

by solving above we got

$\theta = 164 degree$

3 0

3 years ago

Select all that apply. An acorn falls from a tree. Which of the following statements is true? The force of gravity is acting on

DedPeter [7]

The net force on the acorn is less than the force of gravity.

6 0

3 years ago

Read 2 more answers

Diagram shows the velocity time graph for a particle moving in 16 seconds.

Leya [2.2K]

Answer:

The detailed calculations are shown below;

Explanation:

a)The maximum acceleration of the particle:

It is seen that the maximum change in velocity is at the time between 8s to 10s.

Maximum acceleration: $\frac{V}{t}$

= $\frac{20}{2}$

= 10 m/ $s^{2}$

b) The deceleration of the particle

The velocity of particle is decreased after 10s so,

deceleration = - $\frac{40}{6}$

= - 6.67 m/ $s^{2}$

c)The total distance traveled by the particle = Area under the curve

= $\frac{1}{2}$ * 4*20 + 4*20 + $\frac{1}{2}$ * 2*20+ 2*20+ $\frac{1}{2}$ * 40*16

= 290 m

d)The average velocity of the particle = $\frac{Area under the curve}{Total time}$

= $\frac{290}{16}$

= 18.12 m/s

3 0

3 years ago

What is the resistance ofa wire made of a material with resistivity of 3.2 x 10^-8 Ω.m if its length is 2.5 m and its diameter i

Katarina [22]

R = 0.407Ω.

The resistance R of a particular conductor is related to the resistivity ρ of the material by the equation R = ρL/A, where ρ is the material resistivity, L is the length of the material and A is the cross-sectional area of the material.

To calculate the resistance R of a wire made of a material with resistivity of 3.2x10⁻⁸Ω.m, the length of the wire is 2.5m and its diameter is 0.50mm.

We have to use the equation R = ρL/A but first we have to calculate the cross-sectional area of the wire which is a circle. So, the area of a circle is given by A = πr², with r = d/2. The cross-sectional area of the wire is A = πd²/4. Then:

R =[(3.2x10⁻⁸Ω.m)(2.5m)]/[π(0.5x10⁻³m)²/4]

R = 8x10⁻⁸Ω.m²/1.96x10⁻⁷m²

R = 0.407Ω

5 0

3 years ago