In fair weather, the electric field in the air at a particular location immediately above the Earth's surface is 120 N/C directed downward. (a) What is the surface charge density on the ground? Is it positive or negative? (b) Imagine the surface charge density is uniform over the planet. What then is the charge of the whole surface of the Earth? (c) What is the Earth's electric potential due to this charge? (d) What is the difference in potential between the head and the feet of a person 1.75 m tall? (Ignore any charges in the atmosphere.) (e) Imagine the Moon, with 27.3% of the radius of the Earth, had a charge 27.3% as large, with the same sign. Find the electric force the Earth would then exert on the Moon. (f) State how the answer to part (e) compares with the gravitational force the Earth exerts on the Moon.

Answers

Answer 1

Answer:

a. 1.062 × 10⁻⁹ C/m² b. 5.472 × 10⁵ C c. 7.685 × 10⁹ V d. -210.12 V e. 4.972 × 10³ N f. F the electric force is much less than the gravitational force F₁ of the earth on the moon.

Explanation:

a. The surface charge density D = ε₀E where E = 120 N/C

D = ε₀E = 8.854 × 10⁻¹² F/m × 120 N/C = 1.062 × 10⁻⁹ C/m²

The charge density is positive since the electric field is positive or directed downwards. Only a positive charge could direct an electric field out of itself.

b. Since the surface charge density is uniform over the planet and charge, Q = DA where A = area of earth = 4πr² where r = radius of earth = 6.4 × 10⁶ m.

So Q = DA

= 1.063 × 10⁻⁹ C/m² × 4π × (6.4 × 10⁶ m)²

= 5.4715 × 10⁵ C

≅ 5.472 × 10⁵ C

c. The earth's electric potential due  to this charge Q is V = Q/4πε₀r

= 5.472 × 10⁵ C ÷ (4π × 8.854 × 10⁻¹² F/m × 6.4 × 10⁶ m)

= 5.472 × 10⁵ C ÷ 712.081 × 10⁻⁶ F

= 0.07685 × 10¹¹ V

= 7.685 × 10⁹ V

= 7.685 GV

d. Since V = Q/4πε₀r, and we are going to be dealing with a small change in length compared to r, we differentiate V to get the differential change in potential.

So, dV/dr = -Q/4πε₀r²

dV = -Qdr/4πε₀r² ,dr = 1.75 m

dV = -5.472 × 10⁵ C × 1.75 m ÷ [4π × 8.854 × 10⁻¹² F/m × (6.4 × 10⁶ m)²]

dV = -9.576 × 10⁵ Cm ÷ 4557.318 Fm

dV = -210.124 V

dV ≅ -210.12 V

e. Let Q₁ = charge on moon and Q₂ = charge on earth. Given that Q₁ = 0.273Q₂, the force of attraction between earth and moon is F = Q₁Q₂/4πε₀R² where R = distance between earth and moon = 3.844 × 10⁸ m

F = Q₁Q₂/4πε₀R²  

= 0.273Q²/4πε₀R²

= 0.273 × (5.472 × 10⁵ C)²/ [4π × 8.854 × 10⁻¹² F/m × (3.844 × 10⁸ m)²]

= 8.1744 × 10¹⁰ C²/1644.054 Fm × 10⁴

= 0.004972 × 10⁶ N

= 4.972 × 10³ N

= 4.972 kN

f. The gravitational force between earth and moon F₁ = Gm₁m₂/R² where m₁ = mass of moon = 7.3 × 10²² kg and m₂ = mass of earth = 5.97 × 10²⁴ kg.

F₁ = 6.67 × 10⁻¹¹ Nm²/kg² × 5.97 × 10²⁴ kg × 7.3 × 10²² kg/(3.844 × 10⁸ m)²

= 290.685 × 10³⁵ Nm²/14.776 × 10¹⁶ m²

= 19.67 × 10¹⁹ N

= 1.967 × 10²⁰ N

≅ 2 × 10²⁰ N

Since F₁/F = 1.967 × 10²⁰ N/4.972 × 10³ N = 3.95 × 10¹⁶ ≅ 4 × 10¹⁶.

F the electric force is much less than the gravitational force F₁ of the earth on the moon.


Related Questions

You push a block to the top of an inclined plane. The mechanical advantage of the plane is 5. The inclined plane is 10 meters long. What is the height of the inclined plane?


0.5 m

2 m

50 m

10 m

Answers

Answer:

Height of the inclined plane = 2 m

Explanation:

Given:

Mechanical advantage of the plane = 5 m

Inclined plane = 10 meters

Find:

Height of the inclined plane = ?

Computation:

⇒ Height of the inclined plane = Inclined plane / Mechanical advantage of the plane

⇒ Height of the inclined plane = 10 m / 5 m

Height of the inclined plane = 2 m

How do we determine the age of rocks and other geologic features?

Answers

Answer:To establish the age of a rock or a fossil, researchers use some type of clock to determine the date it was formed. Geologists commonly use radiometric dating methods, based on the natural radioactive decay of certain elements such as potassium and carbon, as reliable clocks to date ancient events.

Explanation:

The distance between Earth and the Moon was determined by measuring the time it took for light waves from Earth to travel to the Moon and back. Why was it not possible to use sound waves for this experiment?

Answers

Answer: there is no sound in space

Explanation: there is no vacum in space for sound to travel, therfore no sound waves

How does increasing the prong angle affect the launch angle and initial speed of the projectile?

Answers

Answer:

48.41 m/s

Explanation:

How do satellites stay in orbit?

Answers

Answer:A satellite maintains its orbit by balancing two factors its velocity the speed it takes to travel in a straight line and the gravitational pull that Earth has on it. A satellite orbiting closer to the Earth requires more velocity to resist the stronger gravitational pull.

Explanation:

Answer: The earth's gravity keeps it in orbit. The satellite's velocity keeps it moving.

Please help me this question
2. The diagram below shows two marbles moving in opposite direction with
speeds as shown.
(a) If the velocity of the 30.0g marble after collision is 0.1m/s to the left
What is the velocity of the 10.0g marble after collision?

(b)Calculate the kinetic energy before and after collision, hence deduce the
value of the kinetic energy lost.

Answers

Answer:

THE DIAGRAM ISNT LOADING HOW DO I HELP YOU

Explanation:

8. A sprinter on a school track team is running north at a velocity of 6.0 m/s. After 5.0 s, she
is running south at 4.0 m/s. Calculate the average acceleration for this interval.

Answers

Answer:

acc. = 4-(-6) /5= 10/5=2 m/s^2

What happens to the induced electric current if the number of loops is increased from one to three?


A. It stays the same.

B. It doubles in magnitude.

C. It triples in magnitude.

D. It decreases by a factor of three.

E. It decreases by a factor of two.

Answers

Answer:

C. It triples in magnitude (PLATO)

When the induced electric current, if the number of loops is increased from one to three, it triples in magnitude. The correct option is C.

What is induced electric current?

A shifting magnetic field causes an induced current. An induced emf accompanies the induced current. Without a battery in the circuit, a current can be generated.

The induced emf can be described using Faraday's law of induction. Induction is the method of creating current in a conductor by exposing the conductor to a shifting magnetic field.

Since there is no actual physical link between the conductor and the magnet, this phenomenon is known as induction. The magnetic field is said to induce the current in the conductor.

Therefore, the correct option is C. It triples in magnitude.

To learn more about electric current, refer to the link:

https://brainly.com/question/30033576

#SPJ2

A spring is 14cm long. Three masses are hung from it and then it is measured again. Now it is 19.5cm long. What force did the three masses provide? The spring constant for the spring is 30N/m.

Answers

Answer:

Gravity

Explanation:

The answer is gravity because when the 3 masses were hung from the spring, gravity pulled the spring towards the ground.

If a 12 V battery is connected to a light bulb with a resistance of 2 ohms, how much current will flow through the light bulb?
Group of answer choices

A. 24 Watts

B. 0.5 amps

C. 6 amps

D. 6 ohms

Answers

Answer:

6amp

Explanation:

From Ohm's Law

V = IR

Where V = 12volts, R = 2ohms

12volts = I × 2ohms

I = 12/2

I = 6amp

The current flowing through the light bulb is 6amp

A way of showing how energy moves through an ecosystem _________

Answers

Explanation:

Plants, as a autotrophs have chlorophyll to capture light energy from sun to make starch and sugar. Then, consumers eat plants, and the sugar is transferred to higher trophic level in a form of organic food. Nevertheless, energy is lost by uneaten food, indigestible food, unabsorbed food, excretory waste (eg co2) and heat loss by respiration.

Answer:

The Food Chain

Explanation:

The food chain is conducted of a web connected to three classifications. Each transfering energy to one a other when nutrients and living matter is passed from producers (one class) to consumers (another class), and is broken down by the decomposers (third class) lastly.

Find the correct statement
The disturbance created by a source of sound in the medium do not travels through the medium but the particles of the medium does.
The disturbance created by a source of sound in the medium travels through the medium and not the particles of the medium
The particles and the disturbance created by a source of sound in the medium do not travels through the medium
The disturbance created by a source of sound in the medium travels through the medium along with the particles of the medium

Answers

Answer:The disturbance created by a source of sound in the medium travels through the medium and not the particles of the medium

Explanation:i hope this is right

In 1825, French scientist François-Vincent Raspail became the first scientist to observe that every cell is produced through cell division. How is cell division different in single-celled organisms than in multi-celled organisms? A. Single-celled organisms duplicate their genetic material twice during cell division. B. Cytokinesis divides single-celled organisms into three daughter cells. C. There is no metaphase for single-celled organisms. D. Cell division results in reproduction in single-celled organisms.

Answers

Answer:  A.

Single-celled organisms duplicate their genetic material twice during cell division

Explanation:

All multicellular organisms use cell division for growth and the maintenance and repair of cells and tissues. Single-celled organisms use cell division as their method of reproduction. Somatic cells contain two copies of each of their chromosomes (one copy from each parent).

Answer:

Cell division results in reproduction in single-celled organisms. The correct option is D.

Explanation:

Single celled organism which are equally known as unicellular organisms are organisms which are made up of one cell. Due to the simplicity of the structure of these organisms, reproduction can be achieved through cell division.

Multicellular organisms as the name implies is made up of multiple cells,unlike unicellular organisms, which are to varying degrees integrated and independent.

Every cell is produced through cell division.

Cell division results to reproduction in single-celled organisms while cell division aids in the formation of gametes, which are cells that combine with others to form sexually produced offspring. It is also responsible for the development of a multi-celled organism from a single fertilised egg cell.

Se debe usar una rampa de 5 m para elevar muebles que pesen 490 N hasta una plataforma a una altura de 2 m. Su propuesta de que la eficiencia de la rampa es del 100%, ¿cuál debe ser la fuerza requerida para levantar cada mueble en la rampa?

Answers

Answer:

F = 180 N

Explanation:

To find the required force you first calculate the angle of the ramp, by using the following relation:

[tex]sin\theta=\frac{2m}{5m}=0.4\\\\\theta=sin^{-1}(0.4)=23.57\°[/tex]

Next, you use the Newton second law to know what is the x component (in a rotated coordinate system) of the gravitational force:

[tex]F_x=mgsin\theta[/tex]

the required force must be, at least, the last force Fx. You know that the weight of the object is 490N = mg. Hence, you have:

[tex]F=F_x=(450N)sin(23.57\°)=180N[/tex]

the required force is 180N

- - - - - - - - - - - - - - - - - - - - - - - -

TRANSLATION:

Para encontrar la fuerza requerida, primero calcule el ángulo de la rampa, utilizando la siguiente relación:

Luego, usa la segunda ley de Newton para saber cuál es el componente x (en un sistema de coordenadas girado) de la fuerza gravitacional:

la fuerza requerida debe ser, al menos, la última fuerza Fx. Sabes que el peso del objeto es 490N = mg. Por lo tanto, tienes:

the lambda baryon has the quark composition uds. which particle has the same electric charge as the lambda baryon?

Answers

Answer:

A particle that has the same charge as lambda baryon is a neutron.

Explanation:

A lambda baryon is a subatomic particle that is made up of three quarks - uds (up, down and strange). It contains the same number of protons and neutrons, and an isotopic spin of 1. It is a family of hadrons just like mesons.

A quark is a fundamental or basic particle that make up a matter. It can combine with two or more to form composite particles (e.g neutron or proton). These basic particles are held by a very strong attractive force. The composite particles are the constituents of the nucleus of an atom.

The particle that has the same electric charge as the lambda baryon is neutron.

What quarks as seen in Lambda?

The lambda is known to be a baryon that  is composed of three quarks. They are:

An upA down A strange quark

The neutron is known to be a kind of subatomic particle that is often written as n or n⁰ . It is known to have a neutral charge and its composition is that of 1 up quark and 2 down quarks.

See full question below

The lambda baryon has the quark composition uds. Which particle has the same electric charge as the lambda baryon?

1. neutron

2 electron

3. proton

4 antimuon

Learn more about electric charge from

https://brainly.com/question/1487561

The maximum range of projectle is R° if projected at angle of 45°. It'll be 300% of Range of projectile if projected at angle? a) 30° b) 45° c) 60° d) 76° Correct answer with good explanation

Answers

Answer:

The maximum range is 300% of the range of the projectile is projected at an angle of 9.74°.

None of the options are correct.

Explanation:

Normally, ignoring air resistance, for projectile motion, the range (horizontal distance travelled) of the motion is given as

R = (u² sin 2θ)/g

where

u = initial velocity of the projectile

θ = angle above the horizontal at which the projectile was launched

g = acceleration due to gravity = 9.8 m/s²

The range is maximum when θ = 45°

R when θ = 45° is

R = (u² sin 90°)/g = (u²/g)

We are then told that this maximum range is 300% of the value obtainable for the range at a particular angle

Maximum range = 3R

(u²/g) = 3(u² sin 2θ)/g

Sin 2θ = (1/3)

2θ = sin⁻¹ (1/3) = 19.47°

θ = (19.47°/2) = 9.74°

Hope this Helps!!!

Two similar metal spheres, A and B, have charges of +2.0 x10 –6 coulomb and +1.0 x10 –6 coulomb, respectively, as shown in the diagram below. What is the charge on each sphere after the spheres make contact and are then separated?

Answers

Answer:

+1.5×10^-6C

................

velocity is a vector quantity, and speed is a scalar quantity. The speed of a car is 20 m/s. What other information do you need in order to know the velocity of the car ?

Answers

Answer:

Direction

Explanation:

Speed is a scalar quantity, that is, it has only magnitude

While velocity is a vector quantity, which has both direction and magnitude.

Velocity is also called speed with direction.

Hence, we need to know the direction in which the car is moving in order to know the velocity.

Why are car radiators painted black?

Answers

Answer:

To absorb heat

Explanation:

A black color is said to absorb much heat . This helps in cooling the engine as the radiator has absorbed the heat efficiently .

Additional Information:

A black object absorbs all wavelengths of light and reflects non , that is why it appears black .The more light an object absorbs , the more heat it absorbs .

It might be a good idea to talk to your parents about alcohol because:

Answers

might stumble upon this substance one day and be curious about what it does.

^^ is the correct answer

What is the electrical force of two punctiform electrical charges of 3ųC and 4ųC respectively at a distance of 10 cm in a vacuum

Answers

Answer:

Electrical force, F = 10.8 N

Explanation:

We have,

Charge 1, [tex]q_1=3\ \mu C=3\times 10^{-6}\ C[/tex]

Charge 2, [tex]q_2=4\ \mu C=4\times 10^{-6}\ C[/tex]

Distance between charges is 10 cm or 0.1 m

It is required find the electric force between two charges. The formula used to find the electrical force is given by :

[tex]F=\dfrac{kq_1q_2}{r^2}[/tex]

k is electrostatic constant

Plugging all the values we get :

[tex]F=\dfrac{9\times 10^{9}\times 3\times 10^{-6}\times 4\times 10^{-6}}{(0.1)^2}\\\\F=10.8\ N[/tex]

So, the electrical force between charges is 10.8 N.

2.09)
What would happen to two objects of different masses that are dropped in a
free fall where there is no air friction or any other forces besides gravity?
A. They would fall with an acceleration of 8.9 m/s2.
B. They would hit the ground at the same time.
C. The heavier object would hit the ground first.
D. Both objects would float away.​

Answers

I think the anser is B ::::::::::::;:;;;;;;;;;;;;;;;;;;;;;;;;;

Answer:

b

Explanation:

If someone showed you two spheres of the same size but with different masses, say 1g and 10kg, and asked which would hit the ground first after being dropped from the Leaning Tower of Pisa, what would you say? If you’re like most people, you would say the 10kg sphere would hit the ground first. Aristotle said so too, and for 1,000 years everyone believed him. But doing the experiment would show you, besides a great view of Pisa, that in fact, both spheres hit the ground at the same time.This is exactly what Galileo did, showing the world that objects of different masses fall at the same rate. (This is also a good example of why it is important to do experiments yourself and not to just take someone else’s word for it.) To start understanding why Galileo was right, we need to understand the difference between several physics words that are often jumbled together and confused: mass, weight, speed, velocity, acceleration, and force.

ASSIGNMENT

1. A resistance of 6ohms is connected in series with another of 3ohms. If a potential difference of 9V is applied across the combination, what is the p.d. across the 6ohms resistance.

Answers

Answer:

Equivalent resistance in series = 6 + 3 = 9 ohms

Current = V/R (ohm's law)

Current = 9/9 = 1 A

P.D. across 6 ohms = IR (ohm's law)

= 1A × 6Ω = 6V

2. An 85.0 kg cart is rolling along a level road at 9.00 m/s. The cart encounters a hill and coasts up the hill. a) Assuming the movement is frictionless, at what vertical height will the cart come to rest? b) Do you need to know the mass of the cart to solve this problem?

Answers

The height attained is 4.13 m and we do not need to know the mass of the cart to solve the question.

Mechanical energy

The term mechanical energy refers to energy possessed by a body by virtue of its position or its state of motion. There are two kinds of mechanical energy which are;

Potential energyKinetic energy

For the question, kinetic energy is equal to potential energy hence;

mgh = 1/2 mv^2

We can cancel out m on both sides such that

gh =1/2v^2

h = 0.5v^2/g

h = 0.5(9)^2/9.8

h =4.13 m

We do not need to know the mass of the cart to solve the problem.

Learn more about mechanical energy: https://brainly.com/question/1932868

A ray of light strikes a plane mirror at an angle of incidence 35°. If the mirror is rotated through 10°.
i. what is the angle of reflection before rotating the mirror?
ii. through what angle is the reflected ray rotated?
iii. what is the angle between the incidence ray and the new reflected ray?

Answers

Answer:

1 35°

2 20°

3 50°

..............

In which direction does the magnetic field in the center of the coil point ?

Answers

Answer:

Answer:

from right

Explanation:

right

Answer:

Left

Explanation:

Finger Grasp Process thingy

as a car drives past a person standing on a sidewalk, the driver keeps a hand on the horn. how does the pitch of the horn differ for the driver and the person standing on the sidewalk?

Answers

Answer:

While the car is going towards the standing person on the sidewalk he is listening the pitch of the horn higher then it is.

When the car passes the person on the sidewalk and goes away, the horn's pitch become lower (for the person standing on the sidewalk).

For the driver, the pitch is always the same.

Explanation:

Is the doppler effect.

When the car is approaching, the sound waves must travel a smaller space than the previous one and they take less time to reach the standing person. So, sound waves reach the standing person with a higher frequency.

It happens the opposite when the car is going away: the sound waves need to travel more space and take more time to reach the person on the sidewalk. So, the frequency of the waves is lower.

how mny hours does it takes you to travel by foot from australia to fiji

Answers

Answer:

About 22 hours in flight time.

Explanation:

It wouldn't give me the walking time.

Hope I helped ya.

< Sarah >

Answer:

Hmm idk u was tryna take the trip or sum

Explanation:

At what angle should two mirrors inclined to produced 10
images during reflection of a body?

Answers

Answer:

36°

Explanation:

let n=10 images

n=360/theta

10=360/theta

theta=360/10

theta=36°

hope you help this

mark me as BRAINLIEST

You decide to work at a heart rate of 150 instead of 120. What area of F.I.T.T. did you change?

Answers

Key concepts

Heart rate

Exercising

The heart

Cardiovascular system

Health

Introduction

As Valentine's Day approaches, we're increasingly confronted with "artistic" images of the heart. Real hearts hardly resemble to two-lobed shapes adorning cards and candy boxes this time of year. And the actual shape of the human heart is important for its function of supplying blood to the entire body. You have likely noticed that your heart beats more quickly when you exercise. But have you ever taken the time to observe how long it takes to return to its normal rate after you're done exercising? In this science activity you'll get to do some exercises to explore your own heart-rate recovery time.

Background

Your heart is continuously beating to keep blood circulating throughout your body. Its rate changes depending on your activity level; it is lower while you are asleep and at rest and higher while you exercise—to supply your muscles with enough freshly oxygenated blood to keep the functioning at a high level. Because your heart is also a muscle, exercise, in turn, helps keep it healthy. The American Heart Association recommends that a person does exercise that is vigorous enough to raise their heart rate to their target heart-rate zone—50 percent to 85 percent of their maximum heart rate, which is 220 beats per minute (bpm) minus their age for adults—for at least 30 minutes on most days, or about 150 minutes a week in total. So for a 20-year-old, the maximum heart rate would be 200 bpm, with a target heart-rate zone of 100 to 170 bpm. (For those 19 or younger, target zones can vary more than they do for adults.)

i think it will help you...if it help you ...please mark brainless

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