1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
alukav5142 [94]
2 years ago
13

Find a numerical value for rhoearth, the average density of the earth in kilograms per cubic meter. Use 6378km for the radius of

the earth, G=6.67×10−11m3/(kg⋅s2), and a value of g at the surface of 9.80m/s2.Express your answer to three significant figures.
Physics
1 answer:
mylen [45]2 years ago
8 0

Answer:

density = 5520 kg/m^3

Explanation:

given that

radius of earth = 6378 km

G = 6.67 x 10⁻¹¹ m³/kg.s²

g = 9.80 m/s²

we know,

g = \dfrac{GM}{r^2}

mass of earth

M = \dfrac{gr^2}{G}

M = \dfrac{9.8 \times (6378 \times 10^3)^2}{6.67 \times 10^{-11}}

M = 5.972 x 10²⁴ kg

density =\dfrac{mass}{volume}

V = volume of the earth = 4/3πr³

V = 4/3 x 3.14 x (6378  x 10³)³

V = 1.08 x 10²¹ m³

density = \dfrac{5.972\times 10^{24}}{1.08\times 10^{21}}

density = 5.52 x 10³  kg/m^3

density = 5520 kg/m^3

You might be interested in
If an airplane is flying directly north at 300.0 km/h, and a crosswind is hitting the airplane at 50.0 km/h from the east, what
Rashid [163]

Answer:

magnitude = 304.14 km/h

direction: 9.46^o West of North

Explanation:

The final plane's vector velocity will be the result of the vector addition of one pointing North of length 300 km/h, another one pointing West of length 50 km/h.

To find the magnitude of the final velocity vector (speed) we need to apply the Pythagorean theorem in a right angle triangle with sides: 300 and 50, and find its hypotenuse:

|v|=\sqrt{300^2+50^2}=\sqrt{92500}  = 304.14 km/h

The actual direction of the plane is calculated using trigonometry, in particular with the arctan function, since the tangent of the angle can be written as:

tan(\theta)=\frac{50}{300} = \frac{1}{6} \\\theta = arctan(\frac{1}{6} ) = 9.46^o

So the resultant velocity vector of the plane has magnitude = 304.14 km/h,

and it points 9.46^o West of the North direction.

3 0
3 years ago
You drop a 0.375 kg ball from a height of 1.37 m. It hits the ground and bounces up again to a height of 0.67 m. How much energy
Radda [10]

2.57 joule energy lose in the bounce .

<u>Explanation</u>:

when ball is the height of 1.37 m from the ground  it has some gravitational potential energy with respect to hits the ground  

Formula for gravitational potential energy given by  

Potential Energy = mgh

Where ,

m = mass  

g = acceleration due to gravity  

h = height

Potential energy when ball hits the ground

m= 0.375 kg

h = 1.37 m

g = 9.8 m/s²

Potential Energy = 0.375\times9.8\times1.37

Potential Energy = 5.03 joule

Potential energy when ball bounces up again

h= 0.67 m

Potential Energy = 0.375\times0.67\times9.8

Potential Energy = 2.46 joule

Energy loss = 5.03 - 2.46 = 2.57 joule

2.57 joule energy lose in the bounce

6 0
2 years ago
A 100 kg bag of sand has a weight on 100 N. When dropped its acceleration is what?
Lyrx [107]
100N describes the weight of the sandbag, while 100kg is the mass of the sandbag.

To calculate acceleration, divide your weight by the mass, thus the accleration is:

100N/100kg = 1(m/s^2)
7 0
2 years ago
Read 2 more answers
I need help on ideas for a science project.. (highschool ideas)
Nana76 [90]

A research question that would complete the third question you need that are related to the first 2 questions which are:

  • “what type of masks help prevent fog on glasses when breathing?”
  • “does a mask’s material affect the level of fog on glasses as an effect of breathing?”

Would be: "Are there any available masks that could prevent fog on glasses that could be improved upon"?

This new research question would help you find out if there is an already existing mask that could be made better.

<h3>What is a Research Question?</h3>

This refers to "a question that a research project sets out to answer". and seeks to give answers to particular phenomena.

Hence, we can see that the new research question Would be: "Are there any available masks that could prevent fog on glasses that could be improved upon"?

This new research question would help you find out if there is an already existing mask that could be made better.

Read more about research questions here:

brainly.com/question/25257437

#SPJ1

8 0
1 year ago
!! 50 points spent, easy points for you. 8th-grade science/physics !!
luda_lava [24]

Answer:

1.mirage

2.lens

3.concave lens

4.convex lens

5.index of refraction

Explanation:

IQ=999999

7 0
2 years ago
Other questions:
  • a shot putter accelerates a 7.3kg shot from rest to 14m/s in 1.5r seconds. what average power was developed?
    15·1 answer
  • In a room that is 2.41 m high, a spring (unstrained length = 0.30 m) hangs from the ceiling. A board whose length is 1.86 m is a
    7·1 answer
  • find the current to run an electrical motor that has an output of 2.1 horsepower and is 71% efficient. operates at 171 volts ans
    8·1 answer
  • Need help with both questions!
    7·1 answer
  • What must be the distance in meters between point charge q1 = 30.3 µC and point charge q2 = -68.2 µC for the electrostatic force
    7·1 answer
  • The water at the top of a waterfall has _____ energy.
    6·2 answers
  • Does a stove have mechanical energy
    15·1 answer
  • Ions having equal charges but masses of M and 2M are accelerated through the same potential difference and then enter a uniform
    15·1 answer
  • Explain why a book placed on a table does not move?
    10·2 answers
  • The intersubjective approach treats individuals within societies as quasi-rational arbiters of societal norms. Which of the foll
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!