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3 years ago

How many planets are there?

2 answers:

Crank3 years ago

7 0

It would be 8 (in our solar system)
Mercury, Venus, Earth :D, Mars, Jupiter, Saturn, Uranus, and Neptune.

Many people believe Pluto is a planet, but it's been made official in 2006 that it should be dubbed a dwarf planet

beks73 [17]3 years ago

5 0

Hi there!

Assuming you're asking about the solar system, there are nine planets. But, if you're wanting to know about the universe, there are trillions and trillions of planets (most of which we haven't yet discovered).

Hope this helps!

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How was the scientific revolution important to the enlightenment

Margaret [11]

Answer: The scientific revolution laid the foundations for the Age of Enlightenment, which centered on reason as the primary source of authority and legitimacy, and emphasized the importance of the scientific method.

Explanation:

7 0

2 years ago

Problem 1: Two sources emit waves that are coherent, in phase, and have wavelengths of 26.0 m. Do the waves interfere constructi

Anton [14]

1) Destructive interference

The condition for constructive interference to occur is:

$\delta = m\lambda$ (1)

where

$\delta =|d_1 -d_2|$ is the path difference, with

$d_1$ is the distance of the point from the first source

$d_2$ is the distance of the point from the second source

m is an integer number

$\lambda$ is the wavelength

In this problem, we have

$d_1 = 78.0 m\\d_2 = 143 m\\\lambda=26.0 m$

So let's use eq.(1) to see if the resulting m is an integer

$\delta =|78.0 m-143 m|=65 m\\m=\frac{\delta }{\lambda}=\frac{65 m}{26.0 m}=2.5$

It is not an integer so constructive interference does not occur.

Let's now analyze the condition for destructive interference:

$\delta = (m+\frac{1}{2})\lambda$ (2)

If we apply the same procedure to eq.(2), we find

$m=\frac{\delta}{\lambda}-\frac{1}{2}=\frac{65.0 m}{26.0 m}-0.5=2$

which is an integer: so, this point is a point of destructive interference.

2) Constructive interference

In this case we have

$d_1 = 91.0 m\\d_2 =221.0 m$

So the path difference is

$\delta =|91.0 m-221.0 m|=130.0 m$

Using the condition for constructive interference:

$m=\frac{\delta }{\lambda}=\frac{130.0 m}{26.0 m}=5$

Which is an integer, so this is a point of constructive interference.

3) Destructive interference

In this case we have

$d_1 = 44.0 m\\d_2 =135.0 m$

So the path difference is

$\delta =|44.0 m-135.0 m|=91.0 m$

Using the condition for constructive interference:

$m=\frac{\delta }{\lambda}=\frac{91.0 m}{26.0 m}=3.5$

This is not an integer, so this is not a point of constructive interference.

So let's use now the condition for destructive interference:

$m=\frac{\delta}{\lambda}-\frac{1}{2}=\frac{91.0 m}{26.0 m}-0.5=3$

which is an integer: so, this point is a point of destructive interference.

3 0

3 years ago

We can expect the force of friction to be greater for an object moving on a surface if the surfaces in contact are

nikitadnepr [17]

Answer:

Explanation:

Friction is caused by how rough and object is, and how much the object weighs, as this causes it to drag more.

8 0

2 years ago

An air conditioner has a power rating of 3000 W and is used daily. Its electrical

Anarel [89]

Answer:

5.714 hours / day

Explanation:

<u>Calculate the hours used in that week </u>

120000 / 3000 = 120 / 3 = 40 hours a week

<u>Calculate the amount it is used in one day</u>

40 / 7 = 5.71428571 hours or 5.714 hours/day

5 0

2 years ago

Read 2 more answers

2. How long must a 400 W electrical engine work in order to produce 300 kJ of work?

yanalaym [24]

Answer:

Explanation:

400 W = 400 J/s

300000 J / 400 J/s = 750 s or 12.5 minutes

7 0

3 years ago