dens = mass/volume. after crushing, vol less so density more. the actual density of the metal is the same, density of can changes
The density of a metal can, whether it is crushed or not, remains the same because density is an intrinsic property of matter, dependent only on the mass and volume of the substance. Changing the can's shape alters its volume but does not affect its mass or its density.
Explanation:The density of a substance is the ratio of its mass to its volume (Density = Mass / Volume). This physical property is intrinsic to the substance, meaning it doesn't change regardless of the quantity or form the material is in.
When you crush a metal can, you're changing its shape and thereby altering its volume. However, the mass remains the same because you haven't removed or added any material. As a result, the density of the metal in the crushed can stays the same as the metal's density before the can was crushed.
Let's consider a practical example: a block of brass and a piece of rebar. Both have the same mass and are made of the same metal, but the block of brass has a larger volume. Nevertheless, the densities of these substances remain constant. That's because density is an intrinsic property, reflecting the compactness of material in a substance. Hence, even though you change the can's shape (thus, its volume), you have no impact on the metal's density.
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hydrostatic pressure is deadly to sea creatures true or false
It is to some sea creatures. Like the ones with air filled areas like lungs and swim bladders
The correct answer is false. Just took the test
What is a molecule?
A. A group of positive ions surrounded by delocalized electrons
B. A group of ionically bonded atoms
C. Two oppositely charged ions
D. A group of covalently bonded atoms
D isd your answer buddy
The light from Star 1 reaches Star 3 in 138 years and Star 2 in 63 years. Which of these conclusions about the stars is correct?
A.The distance between Star 2 and Star 3 is 75 light years.
B.The distance between Star 2 and Star 3 is 201 light years.
C.Star 2 is 138 miles away from Star 3.
D.Star 2 is 63 kilometers away from Star 3.
The correct answer is A
The distance between Star 2 and Star 3 is 75 light years.
Explanation:The distance between stars in space can vary significantly. In our Milky Way galaxy, stars are typically separated by many light-years, with the closest star system, Alpha Centauri, about 4.37 light-years away from our solar system. However, interstellar distances can range from fractions of a light-year to many thousands of light-years, depending on the specific stars and their locations within the galaxy or the universe.
The distance between Star 2 and Star 3 can be calculated by subtracting the time it takes for light to travel from Star 1 to Star 2 (63 years) from the time it takes for light to travel from Star 1 to Star 3 (138 years). So, the distance between Star 2 and Star 3 is 75 light years (option A).
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According to evolutionary-oriented astronomers, the universe came into being by _____, _____ processes.
Fission and fusion process
the first part is physical
Explain why your senses would lead you to believe that the Earth is center of the universe
Answer:
This is due to the apparent movement of the celestial bodies, seen from an observer centered on the Earth. If we did not have knowledge of the advances of science and the latest discoveries, we would think that the Earth is the center of the universe.
For example, for an observer on Earth as a reference system, the Sun moves every day from east to west, as do the planets and all the stars that we observe at night, which leads the observer to believe that those in motion are these bodies outside in the sky while the earth is still and fixed in the universe.
Keep in mind that this theory of geocentrism was widely accepted for a long time in antiquity, until the astronomer Nicolaus Copernicus proposed a completely different and opposite idea, heliocentrism (universe centered on the Sun).
However, at present it is known and accepted that the universe has no center, that the Earth revolves around the Sun and that in reality all the bodies of the universe are in movement.
Our senses, based on our observational perspective, may lead us to believe that Earth is the center of the universe, a belief supported by the ancient geocentric model. The shift to the Copernican principle that positions the Sun at the center of the solar system challenged this perception. In reality, we are part of a vast universe and not at its center.
Explanation:Our senses can lead us to believe that Earth is the center of the universe because our daily observations suggest so. From our vantage point, it appears as if the Sun, Moon, and stars revolve around us, making Earth feel central. This observation is attributed to the geocentric model heavily rooted in ancient astronomical models where Earth was considered the universal center and all celestial bodies moved in circular orbits around it.
However, this perception changed with the introduction of the Copernican principle, which redefined our understanding of celestial mechanics, positioning the Sun as the center of our solar system and not the Earth.
From everyday observation, it does seem like everything in the sky orbits the Earth. This perception is due to our positional perspective, not a reflection of the true cosmic order. The reality is that Earth orbits the Sun, and we are just one of many objects in the universe, not at its center.
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The histogram below shows the number of downloads of a song over time.
Approximately how many downloads were there between 8 p.m and 9 p.m?
Given data:
It is a graphical display where the data is grouped in to rangesA diagram consists rectangles, whose area is proportional to frequency of a variable and whose width is equal to the class interval. It is an accurate representation of the distribution of numerical data.From Figure:
Each box in the graph (small rectangle box) is assumed to be one download. So, in the graph the time between 8 p.m to 9 p.m, the number of downloads are 8.75 approximately (because the last box is incomplete, therefore 8 complete boxes and 9th is more than half).
So, We conclude that the total number of downloads are approximately 9 in the time span of 8 p.m. to 9 p.m.
A bowling bowl is thrown off the top of a building. Determine distance the ball has fallen after falling for 3.0 s. Remember, the gravitational acceleration (g) is 9.8 m/s2. (Hint: d = ½gt2)
d = distance the bowling ball has fallen = ?
g = acceleration due to gravity acting on the ball by earth = 9.8 m/s²
t = time of fall for the ball = 3.0 s
distance the ball has fallen is given as
d = (0.5) g t²
inserting the above values in the equation above
d = (0.5) (9.8 m/s²) (3.0 s)²
d = (0.5) (9.8 m/s²) (9.0 s²)
d = (4.9 m/s²) (9.0 s²)
d = 44.1 m
hence the distance fallen by the ball comes out to be 44.1 m
Here is a force diagram of an object in water. The weight of the object is 15N and the buoyancy force is 17N. Will the object float or sink?
Float
Sink
Stay suspended just under the surface
Answer:
Object will float.
Explanation:
Total force on the body = Weight of body + Buoyancy force on body.
Weight of body = 15 N downwards = 15 N
Buoyancy force on body = 17 N upwards = -17 N
Total force on body = 15 - 17 = -2 N = 2 N upwards
So, the body will float.
Object will float.
Consider a boat heading due east at 15 miles/hour. The water's current is moving at 7.1 miles/hour at 45º south of east. Drag vectors for the boat and the current into the vector addition simulation.
What do Rx, Ry, , and |R| represent in terms of the force of the current, and what do they represent in terms of the forces moving the boat?
If a boat is going East at 15mph and there is a water current going southeast at 45° then the boat is being drifted southward. So since the current is going at an angle then it has a x and y component. So Rx refers to the x-component force of the current and Ry refers to the y-component of the current, and |R| refers to the magnitude of these forces.
Answer:
The boat velocity is 20.6 mph and 14 south of east
Explanation:
For this exercise it is best to write the speeds based on its components x and y
Boat V1x = 15 mph
Water V2 = 7.1 mph
θ = - 45º
Where the angle is measured from the x axis, the negative indicates that it is measured on an hourly basis
V2x = V2 cos (-45) = 7.1 (0.707)
V2y = V2 sin (-45) = 7.1 (-0.707)
V2x = 5.0 mph
V2y = -5.0 mph
The total system speed is the sum of each component
Vx = V1x + V2x
Vy = V1y + V2y
Vx = 15 + 5.0
Vy = 0 -5
Vx = 20 mph
Vy = -5.0 mph
We can give result in the form of magnitude and angle
V² = Vx² + Vy²
θ = tan-1 (Vy / Vx)
V = √ [20² ++ (-5)²]
θ = tan-1 (-5/20)
V = 20.6 mph
θ = -14º
The boat velocity is 20.6 mph and 14 south of east
The waters of a lake will be most layered in which season
A. winter
B. spring
C. summer
D. fall
Your answer is C) Summer
I think that the waters of a lake will be most layered in spring
Identify the examples of values. Check all that apply. Inez thinks it is important to be honest with her friends. Molly was raised in a foreign country. Byron tries to treat all people with respect. Lydia cares about expressing her creativity. Armando enjoys playing basketball. Marc would like to learn more about fashion.
Answer:
Inez thinks it is important to be honest with her friends.
Byron tries to treat all people with respect.
Lydia cares about expressing her creativity.
Explanation:
Just did on Edge
If mechanical energy is conserved in a system the energy at any point in time can be in the form of
potential, kinetic, elastc energies
The mechanical energy of the system at any point in time can be in the form of kinetic energy, potential energy, and elastic energy. These all are interconvertible, hence mechanical energy is conserved.
What is Mechanical Energy?The term mechanical energy accounts for the total energy by the virtue of position as well as the motion of an object.
When an object is dropped from a certain height, then the mechanical energy of the object at any instant is given as the sum of kinetic energy and potential energy. The expression is given as,
ME = KE + PE
But at some point in time, the potential energy can be in the form of elastic energy as well. This energy is known as spring potential energy. Hence, the mechanical energy is conserved in a system at any point considering the forms like kinetic energy, potential energy, and elastic energy.
Thus, we can conclude that the mechanical energy of the system at any point in time can be in the form of kinetic energy, potential energy, and elastic energy. These all are interconvertible, hence mechanical energy is conserved.
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To get a sample material from the mantle, drilling will be done through the oceanic crust rather than through the continental crust because oceanic crust it? Explain why?
1)younger than the continental drift.
2)more dense than continental crust.
3)thinner than the continental crust.
4)softer than continental crust.
To get a sample material from the mantle, drilling will be done through the oceanic crust rather than through the continental crust because oceanic crust is thinner than continental crust. Continental crust is thicker than oceanic crust and it is composed of granite. Oceanic crust is easily drilled.
oceanic crust is younger than continental crust but it does not provide any advantage in drilling so it is not a reason.
oceanic crust is more dense than continetal crust but it also not provide any advantage in drilling so it is not a reason
Answer:
Option (3)
Explanation:
The oceanic crust has a thickness of about 7 to 10 km on average, which is much thinner than the continental crust. In order to obtain the rock sample from the mantle, drilling must be done through the rocks of oceanic crust. It is because the depth from the seafloor up to mantle will be much lesser than the depth from the surface of the continental crust to the mantle.
It will require a comparatively lesser amount of money for excavation, in comparison to the drilling done from the continental surface.
Thus, drilling is more favorable to obtain mantle rocks from the oceanic crust.
Hence, the correct answer is option (3).
A model rocket weighing 4.9 N launches from a pad. How much work does the little rocket engine do in the first 4 meters
Answer:
Work done by the little rocket engine = 19.6 Joules.
Explanation:
We know that work = force x displacement.
Force = weight of rocket = 4.9 N
Displacement = 5 meter.
So work done by the little rocket engine = Weight of rocket x displacement.
Work done by the little rocket engine = 4.9 x 4 = 19.6 J
Work done by the little rocket engine = 19.6 Joules.
Suppose that we look at a photograph of many galaxies. Assuming that all galaxies formed at about the same time, which galaxy in the picture is the youngest?
a. the one that is closest to us
b. the one that appears smallest in size
c. the one that is farthest away
d. the one that is bluest in color
e. the one that is reddest in color
A. The one that is closet to us
A trumpet player is playing a musical note. A boy is running at a constant velocity toward the trumpet player, then stops quickly when he is 2.0 meters away. As the boy stops running, what change in pitch, if any, occurs to the musical note he perceives?
The pitch becomes higher
The pitch remains the same
The pitch becomes lower
According to Doppler's law when a listener move towards a source of sound at rest, the frequency observed by the listener is greater than the actual frequency of sound coming from the source. This observed frequency by the listener is given as
f' = (V + v) f/V
where f = actual frequency of the sound from source
V = speed of sound , v = speed of listener towards the source.
Since (V+v)/v > 1
hence f'> f
but when the boy stops , he starts hearing the actual frequency of sound from the source which is smaller to what he was hearing before stopping. hence
The pitch becomes lower
A gargoyle statue falls off the side of a building from a height of 75 m . How long did it take to reach the ground
Distance of a fall from rest = (1/2) (g) (Time²)
75 m = (1/2) (9.8 m/s²) (Time²)
75 m = (4.9 m/s²) (Time²)
Divide each side by (4.9 m/s²):
Time² = (75 m) / (4.9 m/s²)
Time² = (15.3) (s²)
Square-root both sides:
Time = 3.91 seconds
Final answer:
Using the equation for free fall under gravity, it takes approximately 3.91 seconds for a gargoyle statue to reach the ground when dropped from a height of 75 meters.
Explanation:
To calculate how long it takes for a gargoyle statue to reach the ground from a height of 75 meters, we can use the kinematic equation for freely falling objects under gravity (ignoring air resistance). The equation used to determine the time taken (t) is:
\( h = \frac{1}{2}gt^2 \)
Where:
h is the height from which the object falls (75 meters),
g is the acceleration due to gravity \(9.8\, m/s^2\) on Earth,
t is the time in seconds.
By rearranging the formula and solving for t we get:
\( t = \sqrt{\frac{2h}{g}} \)
Plugging in the values:
\( t = \sqrt{\frac{2 \times 75}{9.8}} = \sqrt{\frac{150}{9.8}} = \sqrt{15.30612} \approx 3.91 \text{ seconds} \)
Therefore, it takes approximately 3.91 seconds for the gargoyle to reach the ground.
Satellite technology has allowed us to monitor areas that were once so remote that we had no way of monitoring them. Review the statements and choose the one that best describes how we can use this technology to benefit the environment.
Large ocean liners use satellites to aid in navigation. This type of navigation aid is also used on cruise ships. Using satellites can help these large ships navigate waters during bad storms.
Satellite surveillance can be used to aid in port security. Satellite data can be monitored and evaluated by complex computer systems. These systems can alert officials when something unusual occurs.
Satellite technology allows us to monitor and track the changes in the polar ice sheets. This can help us plan and direct conservation efforts for the animals that depend on polar ice in order to survive.
Satellite surveillance has allowed us to map areas that were previously too remote to observe. This helps developers to locate and choose sites for large resorts.
Answer: Satellite technology allows us to monitor and track the changes in the polar ice sheets. This can help us plan and direct conservation efforts for the animals that depend on polar ice in order to survive.
Explanation:
A satellite orbits around Earth. We have different satellites for different purposes. A satellite has transmitter and receiver for sending and receiving information. For the use of environment, only one statement seems correct that is: Satellite technology allows us to monitor and track the changes in the polar ice sheets. This can help us plan and direct conservation efforts for the animals that depend on polar ice in order to survive.
Rest options are true but not from the environment point of view.
We know that animals are dependent on the environment for their survival. polar ice caps are difficult to reach and monitor. For making conservation plan for the animals residing in these remote areas, satellite technology is very crucial.
Answer:
Satellite technology allows us to monitor and track the changes in the polar ice sheets. This can help us plan and direct conservation efforts for the animals that depend on polar ice in order to survive.
Explanation:
. What is the relationship between potential energy, kinetic energy, and speed as the skater moves down and up the U-shaped ramp?
They are in the inverse relationship between potential energy, and kinetic energy.
What is kinetic energy?The energy of the body by the virtue of its motion is known as the kinetic energy of the body. It is defined as the product of half of mass and square of the velocity.
According to the law of conservation of energy, total energy is defined as the sum of kinetic energy and potential energy.
Total energy = kinetic energy+potential energy
At the top of the U ramp, potential energy is greatest, while kinetic energy is least. The potential energy is the lowest and the kinetic energy is the largest at the bottom of the U ramp.
Hence, PE and KE have an inverse relationship.
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How much current is in a circuit that includes a 9.0 volt battery and a bulb woth a resistance of 4.0 ohms
According to Ohm's law for a portion of the circuit we have:
U=RI=>I=U/R=9/4=2.25 A
Answer:
Current in the circuit, I = 2.25 A
Explanation:
Given that,
Voltage of the battery, V = 9 V
Resistance of the bulb, R = 4 ohms
We need to find the current in the circuit. It can be calculated using Ohm's law. Ohm's law gives the relationship between the current, resistance and the voltage as :
[tex]V=IR[/tex]
[tex]I=\dfrac{V}{R}[/tex]
[tex]I=\dfrac{9\ V}{4\ \Omega}[/tex]
I = 2.25 A
So, the current flowing in the circuit is 2.25 amperes. Hence, this is the required solution.
The metric unit of force is the _____.
A.newton
B.pound
C.kilogram
D.watt
A force is calculated in neutons
Answer: newton
Explanation:
The dodo bird is now extinct. What factor would not have led to its extinction?
A) The forests the dodo lived in where cut down.
B) Sailors landed on the island and killed many for food.
C) It was well adapted to living on the island of Mauritius.
The well adaptability of dodo's in living on the island of Mauritius is the factor that would not have led to dodo's extinction.
What is dodo bird?Dodo is a bird that cannot fly i.e. it is flightless. It is now extinct. Earlier it was found in Mauritius to the east of Madagascar. Rodrigues solitaire, which are genetically related to dodo bird are also categorized as extinct.Given is to find the factor would not have led to the extinction of dodo birds.
If the forests are cut down or Sailors would have landed to kill many for food, it would lead to the extinction of dodo birds. The factor that would not have led to dodo's extinction is the well adaptability of dodo's in living on the island of Mauritius.Therefore, the well adaptability of dodo's in living on the island of Mauritius is the factor that would not have led to dodo's extinction.
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apple newest ipad pro has a storage option of up to 128gb (gigabytes). how many bytes of storage will it have? use a conversion factor, and provide your answer in standard form and scientific notation
Explanation:
Storage offered by iPad pro = 128 gb
1 gigabyte = 1000,000,000 bytes
[tex]1 gb = 1\times 10^{9} bytes[/tex]
[tex]128 gb=128\times 10^9 bytes=128\times 10^9 bytes[/tex]
Standard form = 128,000,000,000 bytes of storage
Scientific notation = [tex]1.28\times 10^{11} \text{bytes of storage}[/tex]
The Apple iPad Pro with 128 GB of storage holds 137438953472 bytes of storage which in scientific notation would be written as 1.3744 x 10^11 bytes.
Explanation:To find the number of bytes in 128 gigabytes (GB), we use the conversion factor that 1 GB is equal to 1024 megabytes (MB), and 1 MB is equal to 1024 kilobytes (KB), and 1 KB is equal to 1024 bytes. So, to convert 128 GB to bytes, we would do the following: 128 GB * 1024 (to get MB) * 1024 (to get KB) * 1024 (to get bytes).
Doing this calculation gives us a total of 137438953472 bytes. In scientific notation, this would be written as 1.3744 x 10^11 bytes.
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3)
Which bones are used to determine age?
A) skull, femur, spine, and phalanges
B) radius, ulna, spine, and femur
C) skull, clavicle, sternum, and sacrum
D) femur, sacrum, pelvis, and skull
4)
How many teeth does a human adult have?
A) 25
B) 27
C) 30
D) 32
5)
Shelia was abducted from a school football field, taken to a bank, and forced to withdraw money from an ATM machine. Afterward, she was left abandoned in a car at a local park. Which is the primary crime scene?
A) bank ATM
B) car
C) park
D) football field
Eliminate
D. Femur, sacrum, pelvis and skull
Nyah explains to Arman the importance of decomposers in an ecosystem. Which sentence(s) should she use in her explanation? Select all that apply.
A.) Decomposers provide food for consumers.
B.) An ecosystem cannot function without decomposers.
C.) Most ecosystems have only one type of decomposer.
D.) Decomposers help to recycle nutrients in an ecosystem
E.) Fungi, plants, and insects are examples of decomposers.
The Sentences Nyah should use in her Explanation are :
B. An Ecosystem cannot Function without Decomposers.
D. Decomposers help to recycle nutrients in an Ecosystem.
Because :
✿ Producers provide food for Consumers.
✿ Ecosystems have many types of Decomposers like Bacteria & Fungi.
✿ Plants are not Examples of Decomposers.
Final answer:
Decomposers like fungi and bacteria are crucial for ecosystem functionality as they recycle nutrients, enabling the survival and stability of ecosystems. They prevent waste buildup and support the cycle of life by converting dead matter into essential nutrients for producers.
Explanation:
Nyah explains to Arman the importance of decomposers in an ecosystem. The sentences that should be used in her explanation are:
B.) An ecosystem cannot function without decomposers.
D.) Decomposers help to recycle nutrients in an ecosystem.
Decomposers, such as fungi and bacteria, play a critical role in sustaining ecosystems by breaking down dead organisms and organic waste. This process recycles essential nutrients like carbon and nitrogen back into the soil, which are then available for producers, such as plants, to use. By converting dead matter into nutrients, decomposers ensure the stability and survival of ecosystems, preventing waste accumulation and enabling the continuous cycle of life.
label the parts of a wave the terms : crest ,trough, frequency, wavelength, amplitude
We have that Crest ,trough, frequency, wavelength, amplitude you will be able to label the wave in Question.
From the question we are told
Label the parts of a wave the terms : crest ,trough, frequency, wavelength, amplitude
Generally
CrestThis is the defined as the vertical distance covered by a wave.
TroughThis speaks of lowest point of a wave the inverse of the crest
FrequencyThis is the is defined as the inverse of
WavelengthThis is defined as the peak to peak distance of a wave
AmplitudeThis defines the maximum height attained by the wave.
Therefore
With above definition of Crest ,trough, frequency, wavelength, amplitude you will be able to label the graph in Question
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When you look at the isotopes of one element, the number of protons__________
Answers:
Changes, Stays the Same
Answer: the number protons stayed the same.
Explanation: an isotope has equal number of protons but different number of neutrons resulting in different atomic mass but the same chemical properties.
How did Ernest Rutherford change the atomic model based on his experimental results?
A. He placed electrons in orbits around the nucleus.
B. He described the atom as a sea of positive charge sprinkled with electrons.
C. He placed positive material in the atom's center.
D. He described electrons as being in clouds outside the nucleus.
You have two answers that are pretty close. He mentioned D, but what he really found and stuck with it and concentrated on it when submitting his findings was that the nucleus of an atom was small and concentrated at the center of the atom.
So the answer is C but you cannot easily eliminate D. I think the question is somewhat faulty, but C should give you the mark.
Answer:
C. He placed positive material in the atom's center.
Explanation:
Ernest Rutherford was a physicist from New Zealand who spent most of his career in England and Canada. Rutherford was an important figure in the history of the discovery of the atom. Rutherford is famous for his gold foil experiment. Based on the results of his experiment, Rutherford concluded that there must be a tiny volume of the atom, containing most of the atom's mass, at the center of the atom. This would have a positive charge, and the rest of the atom must be made of mostly empty space. This positive material in the atom's center is the nucleus.
A rocket ship starts from rest and turns on its forward booster rockets, causing it to have a constant acceleration of 4 \,\dfrac{\text m}{{\text s}^2}4 s 2 m ? rightward. After 3\,\text s3s, what will be the velocity of the rocket ship? Answer using a coordinate system where rightward is positive.
Answer:
+12 m/s
Explanation:
The velocity of an object moving of accelerated motion is given by:
[tex]v(t) = v_0 +at[/tex]
where
v0 is the initial velocity of the object
a is the acceleration
t is the time
In this problem, the rocket starts from rest, so [tex]v_0 =0[/tex]. The acceleration is [tex]a=4 m/s^2[/tex], so the velocity after [tex]t=3 s[/tex] will be
[tex]v(3 s)=0 +(4 m/s^2)(3 s)=+12 m/s[/tex]
Help with 5 and the question below. BRAINLIEST FOR THE CORRECT ANSWER! Urgent Physics help!
You are trying to hear your friend give directions to new store in town. But from your distance of 15 m you only hear a whisper of about 20 dB intensity. You move closer to bring the conversation up to a sound level of about 50 dB. How close do you need to be?
100 cm
333 cm
90 cm
47 cm
90 cm
Sound level at distance of 15 m is given as 20 dB
so intensity at this distance is given as
[tex]L = 10 Log\frac{I}{I_0}[/tex]
[tex]20 = 10 Log{I}{10^{-12}}[/tex]
[tex]I_1 = 10^{-10}W/m^2[/tex]
now if we move closer to some some distance the sound level is now 50 dB
now the intensity is given as
[tex]L = 10 Log\frac{I}{I_0}[/tex]
[tex]50 = 10Log\frac{I}{10^{-12}}[/tex]
[tex]I_2 = 10^{-7}W/m^2[/tex]
now we know that
[tex]\frac{I_1}{I_2} = \frac{r_2^2}{r_1^2}[/tex]
[tex]\frac{10^{-10}}{10^{-7}} = \frac{r_2^2}{15^2}[/tex]
[tex]r_2 = 47 cm[/tex]
so now the distance from friend must be 47 cm