a body weights 28N at a height of 3200km from the earth surface.What will be the gravitational force on that body if its lies on the earth surface.

Answers

Answer 1

Answer:

The object would weight 63 N on the Earth surface

Explanation:

We can use the general expression for the gravitational force between two objects to solve this problem, considering that in both cases, the mass of the Earth is the same. Notice as well that we know the gravitational force (weight) of the object at 3200 km from the Earth surface, which is (3200 + 6400 = 9600 km) from the center of the Earth:

[tex]F_G=G\,\frac{M_E\,m}{d^2} \\28\,\,N=G\,\frac{M_E\,m}{9600000^2}[/tex]

Now, if the body is on the surface of the Earth, its weight (w) would be:

[tex]F_G=G\,\frac{M_E\,m}{d^2} \\w=G\,\frac{M_E\,m}{6400000^2}[/tex]

Now we can divide term by term the two equations above, to cancel out common factors and end up with a simple proportion:

[tex]\frac{w}{28} =\frac{9600000^2}{6400000^2} \\\frac{w}{28} =\frac{9}{4} \\\\ \\w=\frac{9\,*\,28}{4}\,\,\,N\\w=63\,\,N \\[/tex]


Related Questions

What is at the very center of our galaxy? This question is difficult to answer because the center is completely obscured to our eyes behind a large amount of dust. On the basis of what you know about dust from previous chapters, what can be done to improve our view of the galaxy’s center?

Answers

Answer:

The answer is "Observe it in the infrared"

Explanation:

The infrared observatory is a device, which helps to track but also fix thermal light from sources out and the front of Earth's atmosphere like nebulae, young stars, and dust and gas in several other galaxies.

The very center of our galaxy is like a star cluster is situated in the central of our universe across the Milky Way supermassive, and the central black hole, around 4 million times our sun's mass.

The main super black hole named the Sagittarius A-star has been located in the nucleus of the galaxy, that's why in this question "Observe it in the infrared" is the correct answer.

Consider how the spectrum of visible light is dispersed by a prism and by a diffraction grating. Which description is most complete? Question 2 options: A prism bends blue light more than red light but the angle of diffraction for blue light is less than for red light. White light can pass with no dispersion through a prism but not through a diffraction grating. There is little difference in how light is dispersed by the two methods. The diffraction grating behavior is based on Snell's Law and the prism behavior is based on the index of refraction.

Answers

Answer:

a) pridm       sin θ₂ = (sin θ) / n

b) red                sin θ= mλ/a

Explanation:

The scattering of light in its spectrum occurs by two different phenomena. In the case of the prism, light is scattered because the index of refraction of the material depends on the wavelength, according to the law of refraction.

          n₁ sin θ₁ = n₂ sin θ₂

if the cousin is in the air n1 = 1 and n2 is the refractive index of the prism

              sin θ₂ = (sin θ) / n

Since the refractive index depends on the wavelength, light is scattered in its spectrum.

For the diffraction grating, the dispersion adhesiveness to diffraction in multiple slits, and is described by the expression

              a sin θ =  mλ

              sin θ= mλ/a

where m is an integer indicating the order of the spectrum, the separation is due to the change in wavelength.

In black the separation of the network is much greater in the network because a is very small and in the prism the change of the index of refraction is small.

This mathematical model describes the changes that occur in a sample of
water as its temperature increases. Use this model to predict what will
happen to the motion of the molecules in a sample of water that is being
heated from 50° to 100°C.
200°C
vaporization
150°C
melting
100°C
Temperature (°C)
water vapor
50°C
liquid water
0°C-
--50°C
10
20
ice
30
Time (min)
40
50
60
70
O A. The motion will change very little.
O B. The molecules will stop moving.
O C. The movement of the molecules will gradually decrease.
O D. The movement of the molecules will gradually increase.

Answers

The correct answer is D. The movement of the molecules will gradually increase.

Explanation:

At the beginning of the model the state of matter of the water is solid, in this, particles have a defined arrangement and are together, which stops particles from moving freely and only allows them to vibrate. However, as the substance is heated the thermal energy (heat) increases in the sample, this causes particles to move more and the arrangement of it changes. Due to this, when the ice melts and there is liquid water particles move more than in solid states, which makes ice lacks a defined shape. Moreover, as the heat continues to increase the thermal and kinetic energy (movement) increases, indeed in gas state (water vapor) particles will move freely. This means the movement or kinetic energy in particles gradually increases in the model.

Answer: D

Explanation:

Some students set up a circuit and decided to measure the voltage at different points around
the circuit. (Assume all the resistance are the same.)
What was the voltage reading shown on Voltmeter 1,2 and 3? If you know the answer please explain bc I have no idea :)

Answers

Answer:

 V₁ = 6 V ,  V₂ = V₃ = 3 V

Explanation:

To solve this circuit we must remember that there are two fundamental types of construction in series and parallel.

* a serial circuit there is only one path for current

in this circuit the constant current in the entire circuit and the voltage is the sum of the voltage of each term

* Parallel circuit in this there are two or more paths for the current

in this circuit the voltage is constant and the east is divided between each branch

with these principles let's analyze the proposed circuit

The DC battery is in parallel with resistor R1 and the equivalent of the other branch,

as in a parallel circuit the voltage is constant

               V₁ = 6 V

in the other branch (23) it forms a series construction, where the current is constant

               6 = iR₂ + iR₃

as they indicate that each resistance has the same value

              6 = 2 iR

              V = V₂ = V₃ = 3 V

A ray diagram is shown. A light ray strikes a boundary and a second vector into the second material. The second light ray is closer to the normal. What does theta2 represent? index of refraction index of reflection angle of incidence angle of refraction

Answers

Answer:

Angle of refraction.

Explanation:

Refraction is simply a change in direction of light rays as it enters into another medium.

In the diagram given above, θ2 is simply the angle of refraction showing us that the light ray has changed direction as it moves from one medium to another medium.

The angle  θ2 is the angle that shows the degree of the bending of the light ray and is called the anglle of refraction.

What is refraction?

The term refraction has to do with the bending of light rays as it crosss the boundary between two media. Now. we can see that the ray of ligh as shown in the image is undergoing refraction.

Now the angle that has been marked θ2 is the angle that shows the degree of the bending of the light ray and is called the anglle of refraction.

Learn more about refraction: https://brainly.com/question/14760207

This is a form of energy representing the motion of the molecules which make up an object. A. Thermal Energy B. Kinetic Energy C. Gravitational Potential Energy D. Chemical Potential Energy

Answers

Answer:

Kinetic energy.

Explanation:

There are many kinds of energy. Some of them are kinetic energy, potential energy, thermal energy etc. The energy that shows the motion of the object is called its kinetic energy.Also, the sum of kinetic energy and the gravitational potential energy is called mechanical energy. Out of the given options, kinetic energy is the form of energy that represents the motion of the molecules which make up an object. Hence, the correct option is (B).

How do you find the rest mass (kg) of a 3.1 eV electron?

Answers

Answer:

Explanation:

The rest energy of any substance is defined by the Einstein's mass energy equivalence relation. Thus the rest mass of a electron is 9.11x10^-31 kg. The speed of light is 299,792,458 m/s. Thus multiplying the square of speed of light with the rest mass of electron gives the rest energy of the electron.

Unit of energy density of electric field is a) NC-3 b) JC-3 c) Jm-3 d)JF

Answers

Answer:

the answer is c

The answer is C being JM-3

What is difference between gravity and gravitational force

Answers

gravity means that is not a force but the gravitational force is a force

For example we call the earth has a gravitational force but on moon we say that it doesn't have gravity

Answer:

Gravity is the Earth’s pull on a body, lying on near the surface of the Earth.

Gravitational force is the force of attraction acting between any two bodies.

Which of the following statements describes nucleons?
A. Nucleons are the particles that make up a nucleus.
B. Nucleons are the particles in an atom that are neutral.
C. Nucleons are the particles that make up an atom.
D. Nucleons are the particles in an atom that have a charge.

Answers

Answer: nucleons are the particles that make up in nucleus

Explanation:

Nucleons are the particles that make up a nucleus, and they include protons and neutrons.

What are nucleons?

Nucleons are particles that make up nucleus of an atom. They include either proton or neutron, or both found in atomic nucleus.

Generally, nucleons are subatomic particles found within nucleus of an atom.

Therefore, we can conclude that, nucleons are the particles that make up a nucleus.

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What is electromagnet and list the types of electromagnet.​

Answers

Answer:

radio waves, micro wave, x-rays

Explanation:

Explanation:

A MAGNET IN WHICH MAGNETIC FIELD IS PRODUCED BY ELECTRIC CURRENT IS CALLED ELECTROMAGNET.

THE ELECTROMAGNETS ARE HAVE 3 TYPES. THERE ARE:

◇ ROBUST ONES

◇ THE SUPERCONDUCTORS

◇ HYBRIDS.

EXAMPLES OF ELECTROMAGNETS: RADIO WAVES, MICROWAVE, X-RAYS.

HOPE IT HELP...❤❤

electronegativity increases when atoms ___
A.have a small atomic radius
B.are located in the right on the periodic table
C.are located on the left on the periodic table
D.have a large atomic radius

Answers

your answer is.....

D. have a large atomic radius

although they also increase going from left to right so if D is incorrect, B might be your answer. it depends on context of the lesson.

What is Cognitive Behavioural Therapy?

Answers

Answer:-

Cognitive behavioral therapy (CBT) is a form of psychological treatment that has been demonstrated to be effective for a range of problems including depression, anxiety disorders, alcohol and drug use problems, marital problems, eating disorders and severe mental illness.  CBT leads to significant improvement in functioning and quality of life.

Hope this help :)

And can u give brainliest.

The goal of cognitive behavioral therapy (CBT), a type of psychotherapy, is to alter unhelpful thought and behavior patterns.

What is Cognitive Behavioural Therapy?

Cognitive Behavioral Therapy (CBT) is a form of psychotherapy that focuses on changing negative patterns of thinking and behavior. It is a goal-oriented and structured therapy that aims to help individuals identify and modify their thoughts and behaviors that may be contributing to psychological distress.

CBT is based on the idea that the way people think about a situation affects how they feel and how they behave. In CBT, therapists work with clients to identify and challenge negative and irrational thoughts and beliefs, and replace them with more realistic and positive ones. This can lead to improved mood and behavior.

CBT is a collaborative therapy, where the therapist and client work together to set goals and develop strategies to achieve them. CBT typically involves a specific number of sessions, with the number and frequency of sessions varying depending on the individual's needs and goals.

CBT has been found to be effective in treating a wide range of mental health issues, including anxiety disorders, depression, post-traumatic stress disorder, obsessive-compulsive disorder, and eating disorders. It is often used in combination with other treatments, such as medication, and can also be adapted for use with children and adolescents.

Therefore, To change unhelpful thought and behavior patterns is the aim of cognitive behavior therapy (CBT), a type of psychotherapy.

To learn more about Cognitive Behavior Therapy (CBT) click:

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What is the resistance In a circuit that carries 0.75A current when powered by a 1.5 V battery?

Answers

Answer:

2.0 Ω

Explanation:

V = IR

1.5 V = (0.75 A) R

R = 2.0 Ω

Energy of the fossil fuels is also derived from solar energy. Give reason.​

Answers

Answer:

Explanation:

All the energy in oil, gas, and coal originally came from the sun, captured through photosynthesis. In the same way that we burn wood to release energy that trees capture from the sun, we burn fossil fuels to release the energy that ancient plants captured from the sun

define motion also justify that rest and motion are related terms​

Answers

Answer;

Motion: A body is said to be in motion if it changes its position with respect to its surroundings.

Explanation:

Rest and motion are the relative terms because they depend on the observer's frame of reference. So if two different observers are not at rest with respect to each other, then they too get different results when they observe the motion or rest of a body .

one example for each. Rest: If a body does not change its position with respect to its surroundings, the body is said to be at rest. ... Motion: A body is said to be in motion if it changes its position with respect to its surroundings.

Negative ions have _____.

Answers

A negaive ion has more electrons bound to it than protons in its nucleus.

Suppose the position of an object moving in a straight line is given by s (t )equals 5 t cubed minus 2 t squared plus 9. Find the instantaneous velocity when tequals7.

Answers

Answer:

Explanation:

s(t) = 5t³-2t²+9

Instantaneous velocity v = ds / dt

v = ds/dt = 15t²-4t

Putting t = 7

v = 15 x 7² - 4 x 7

= 707

Instantaneous velocity at t = 7

is 707 unit .

A car engine burns gas at 495 K and exhausts to the air at 293 K. What is the highest possible efficiency it could have?
(NO UNIT)

Answers

Answer:

59.19%

Explanation:

Step 1:

Data obtained from the question. This include the following:

Input temperature = 495 K.

Output temperature = 293 K.

Efficiency =..?

Step 2:

Determination of the efficiency of the engine.

Efficiency is simply defined as the ratio of output to input times 100. Mathematically, it is expressed as:

Efficiency = output /input x 100

With the above formula, we can calculate the efficiency of the engine as follow:

Input temperature = 495 K.

Output temperature = 293 K.

Efficiency =..?

Efficiency = output /input x 100

Efficiency = 293/495 x 100

Efficiency = 59.19%

Therefore, the efficiency of the engine is 59.19%

Answer:

0.41

Explanation:

Trust me bro

Suppose a point charge is located at the center of a spherical surface. The electric field at the surface of the sphere and the total flux through the sphere are determined. Now the radius of the sphere is halved. What happens to the flux through the sphere and the magnitude of the electric field

Answers

Answer:

The flux through the sphere will remain the same, and the magnitude of the electric field will increase by four times.

Explanation:

The electric flux is the number of electric field, passing through a given area. It is proportional to the electric field strength and the area through which this field passes.

If the radius of the sphere is halved, the area of the sphere will reduce by square of the reduction, which will be four times. The electric field lines will become closer together, or technically increase by a fourth of its initial value. The resultant effect is that the electric flux will remain the same.

If originally,

Φ = EA cos∅

where Φ is the electric flux through the sphere

E is the electric field on the sphere

A is the area of the sphere.

If the area of the sphere is reduced to half, then,

the area reduces to A/4,

and the electric field increases to be 4E on the sphere.

The flux now becomes

Φ = 4E x A/4 cos∅

which reduces to

Φ = EA cos∅

which is the initial electric flux on the sphere.

PLEASE HELP!!!! i will give brainliest to the first person...

Answers

Answer: Fossil fuels power the machine that shakes the tree so the apples fall to the ground

Explanation: most machines are powered by fossil fuels

what is the meaning of physics​

Answers

Answer:

the branch of science concerned with the nature and properties of matter and energy

20 m
A projectile is fired from the origin (at y = 0 m) as shown in the diagram. The initial velocity components are Vox = 310 m's and Vov = 26 m s The
projectile reaches maximum height at point P. then it falls and strikes the ground at point Q which is 20 m below the launch point. What is the horizontal
distance that the projectile travels (labeled x in the diagram)?
O 1.3 km
700 m
O 32 km
O 870 m
O 1.9 km​

Answers

Answer:

  1.9 km​

Explanation:

The equation for vertical motion is ...

  h(t) = -4.9t^2 +26t +20

This will have a zero near t = 5.988 seconds.*

The horizontal distance traveled in that time is ...

  (310 m/s)(5.988 s) ≈ 1856 m ≈ 1.9 km

_____

* The root of a quadratic can be found numerous ways. We choose the quick and easy: let a graphing calculator show it to you.

Which prefix indicates the smallest part of a unit?
O A. Mega-
B. Milli-
O C. Kilo-
O D. Micro-
SUBM

Answers

The prefix that is the smallest part of a unit is D, MICRO.

A prefix meaning one-millionth (1/1,000,000 or 10-6)

Example:

a micrometer is one-millionth of a meter.

Hope this help!!! :)

The prefix which indicates the smallest part of a unit D. Micro

What is prefix of a unit ?

A unit prefix is that precedes a basic unit of measurement to indicate a multiple or submultiple of the unit .

1 mega = 10^(6)

1 milli = 10^(-3)

1 kilo = 10^(2)

1 micro = 10 ^ (-6)

out of all above prefix of  units d) Micro is the smallest

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On his fishing trip Justin rides in a boat 12 km south. The fish aren’t biting so they go 4 km west. They then follow a school of fish 1 km north. What distance did they cover? What was their displacement?

Answers

Answer:

I think the answer is 8km2

Answer:

Distance = 17km

Displacement = 12.6 km

Explanation:

south 12km

west 4km

north 1km

Total distance = 12 + 4 + 1 = 17km

Total displacement = in picture above.

Find the net force of the box and the acceleration. 10 points. Will give brainliest.

Answers

Answer:

38.6 N

2.57 m/s²

Explanation:

Draw a free body diagram of the box.  There are four forces:

Weight force mg pulling down,

Normal force N pushing up,

Friction force Nμ pushing left,

and applied force P pulling at an angle 40°.

Sum of forces in the y direction:

∑F = ma

N + P sin 40° − mg = 0

N = mg − P sin 40°

The net force in the x direction is:

∑F = P cos 40° − Nμ

∑F = P cos 40° − (mg − P sin 40°) μ

∑F = P cos 40° − mgμ + Pμ sin 40°

∑F = P (cos 40° + μ sin 40°) − mgμ

Plugging in values:

∑F = (80 N) (cos 40° + 0.23 sin 40°) − (15 kg) (10 m/s²) (0.23)

∑F = 38.6 N

Net force equals mass times acceleration:

∑F = ma

38.6 N = (15 kg) a

a = 2.57 m/s²

Which of the following statements are true? (mark all that apply)
a) Light is a form of energy.
b) The rate of flow of energy is measured in Watts.
c) White light is made of all the colors of the rainbow and can be split to show them all including shades of gray all the way to black
d) Black is the absence of light.

Answers

Answer:

(a) and (b)

Explanation:

Energy is the capacity to do work, and exists in various forms. These forms can be converted one to another by the use of appropriate means. Some examples are sound, mechanical, solar, light, which causes the sensation of vision, etc. energy is measured in Joules (J).

The rate of transfer of energy is called power.

i.e Power = [tex]\frac{energy}{time}[/tex]

It is measured in Watts (W).

When a white light is disperses into its colors, gray and black are not part of the colors. And a black sometimes could be as a result of the absorption of all other colors of light.

A body moves in a straight line. At time, it's acceleration is given by a = 12t + 1. When t =0, the velocity of the body v is 2 metres per second and its displacement from the origin s is 0.
1. Express v and s in terms of t.
2. Determine velocity and displacement of the body after 3 seconds. ​

Answers

Answer:

v = 6t² + t + 2, s = 2t³ + ½ t² + 2t

59 m/s, 64.5 m

Explanation:

a = 12t + 1

v = ∫ a dt

v = 6t² + t + C

At t = 0, v = 2.

2 = 6(0)² + (0) + C

2 = C

Therefore, v = 6t² + t + 2.

s = ∫ v dt

s = 2t³ + ½ t² + 2t + C

At t = 0, s = 0.

0 = 2(0)³ + ½ (0)² + 2(0) + C

0 = C

Therefore, s = 2t³ + ½ t² + 2t.

At t = 3:

v = 6(3)² + (3) + 2 = 59

s = 2(3)³ + ½ (3)² + 2(3) = 64.5

A lever is placed on a fulcrum. A rock is placed on the right end of the lever and a downward (counterclockwise) force is applied to the left end of the lever. What measurements would be most effective to help you determine the angular momentum of the system? (Assume the lever itself has negligible mass.)

Answers

Answer:

measurements that would be most effective to help you determine the angular momentum of the system are

the mass of the rock, the length of the lever on both sides of the fulcrum, and the force applied on the right side of the lever

A constant force of 230 N is applied to a 24 kg block of concrete for 25 seconds.

a. What is the final speed of the block if it originally at rest

Answers

Explanation:

a = f/m

a = 230/24 = 9.58m/s²

t = 25secs

u = 0m/s

v = ?

a = (v - u)/t

9.58 = (v - 0)/25

9.58 x 25 = v

v = 238.75m/s

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Which statement best defines a theme in a short story?.A theme is the central message, moral, or lesson conveyed using characters,'setting, and plot.OB.A theme is the topic of a story, which the author develops through a particular tone and mood.O C.A theme helps build tension between the characters in a story.ODA theme is the use of an object to represent a larger idea.OE.A theme helps reveal the order in which events occur in a story. Sketch the graph of y = (x - 3)2 - 16, then select the graph that correspondsto your sketch.10-2020-55. 101020A. Graph AB. Graph BC. Graph C D. Graph D Why was the 1912 election significant?A. Because it showed that the American political landscape was stagnant.B. Because it proved that the Socialists were not as powerful.C. Because American was offered a variety of ideological choices.D. Because it showed that the Republicans were a dominant party.E. Because it showed that the Democrats were a dominant party. 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Read the poem below and answer the question that follows. La Belle Dame sans Merci: A Ballad by John Keats O, what can ail thee, knight-at-arms, Alone and palely loitering? The sedge has withered from the lake, And no birds sing. O what can ail thee, knight-at-arms, So haggard and so woe-begone? The squirrels granary is full, And the harvests done. I see a lily on thy brow, With anguish moist and fever-dew, And on thy cheeks a fading rose Fast withereth too. I met a lady in the meads Full beautifula faerys child, Her hair was long, her foot was light, And her eyes were wild. I made a garland for her head, And bracelets too, and fragrant zone; She looked at me as she did love, And made sweet moan. I set her on my pacing steed, And nothing else saw all day long, For sidelong would she bend, and sing A faerys song. She found me roots of relish sweet, And honey wild, and manna-dew, And sure in language strange she said I love thee true. She took me to her elfin grot, And there she wept and sighed full sore, And there I shut her wild wild eyes With kisses four. And there she lulld me asleep, And there I dreamedAh! woe betide! The latest dream I ever dreamt On the cold hill side. I saw pale kings and princes too, Pale warriors, death-pale were they all; They criedLa Belle Dame sans Merci Thee hath in thrall! I saw their starved lips in the gloam, With horrid warning gapd wide, And I awoke and found me here, On the cold hills side. And this is why I sojourn here, Alone and palely loitering, Though the sedge is withered from the lake, And no birds sing. Source: Keats, John. La Belle Dame sans Merci: A Ballad. Poetry Foundation. Poetry Foundation, n.d. Web. 24 June 2011. Determine the meter of this poem. Which sentence describes the metrical pattern? The meter is iambic with 8 feet in the first 3 lines; the last line has 4 feet. The meter is iambic with 4 feet in the first 3 lines; the last line has 2 feet. 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