Help science 70 points

Answer:

Part A

The sound intensity at the location 150 from the firework = 4.3[tex]\overline 5[/tex] W/m²

Part B

The power the firework is emitting is approximately 1,231.5 kW

Explanation:

Part A

The data of the firework sound heard by the two friends are;

Let 'A' represent the location of the friend at a point 150 m from the fireworks and let 'B' represent the location of the friend watching from a distance of 700 m from the firework

The distance of 'A' from the sound, r₁ = 150 m

The distance of 'B' from the sound, r₂ = 700 m

The intensity at which 'B' hears the sound, I₂ = 0.2 W/m²

The relationship between sound intensity and distance is given as follows;

[tex]\dfrac{I_2}{I_1} = \left (\dfrac{r_1}{r_2} \right )^2[/tex]

[tex]\therefore {I_1} = \dfrac{I_2}{ \left (\dfrac{r_1}{r_2} \right )^2} = I_2 \times \left (\dfrac{r_2}{r_1} \right )^2[/tex]

Plugging in the values gives;

[tex]\therefore {I_1} = 0.2 \times \left (\dfrac{700}{150} \right )^2 = \dfrac{196}{45} = 4.3\overline 5[/tex]

The sound intensity at location 'A', I₁ = 4.3[tex]\overline 5[/tex] W/m²

Part B

The relationship between power, 'P', and intensity, 'I', is presented as follows;

[tex]I = \dfrac{P}{4 \cdot \pi \cdot r^2}[/tex]

P = I·4·π·r² = 4·I·π·r²

Therefore, at point 'A', where the distance, r₁ = 150 m, and the intensity, I₁ = 4.3[tex]\overline 5[/tex] W/m², we have;

P = 4 × 4.3[tex]\overline 5[/tex] W/m² × π × (150 m)² = 1231504.32021 W

The power the firework is emitting, P ≈ 1,231.5 kW.

Answer:

C

Explanation:

Since gravitational force is inversely proportional to the square of the separation distance between the two interacting objects, more separation distance will result in weaker gravitational forces

I hope this helps a little bit

The correct Option is :

=》(C) The square of the distance that separates them

where,

f = gravitational force

r = distance between the objects

Answer:

Magnification, m = 3

Explanation:

It is given that,

Focal length of the lens, f = 15 cm

Object distance, u = -10 cm

Lens formula :

v is image distance

Magnification,

So, the magnification of the lens is 3.

Answer:

31.1

Explanation:

Trust brother

Answer:

=> Rheostat is an electric device used as a variable resistance, like the regulator of the fan. It is used to change the electric resistance in the electric circuit.

=> Rheostat works on the principle of Ohm’s law. Ohm’s law states that current in a circuit is inversely proportional to the resistance at the given temperature.

[tex] \infty \infty \infty [/tex]

Answer:

The shape of a screw is a cylindric shape that grows in diameter at the top. Along the cylindar portion, it has horizantal ridges that circulate around the screw.

Hope this helps, brainliest pls :D

Explanation:

A. True , a base is a substance that forms hydroxide ions in water

hope it helps

you tend to push off with the foot still on the boat.

Newtons 3rd law of motion hold that every action has an equal and opposite reaction.

So, the amount of force you use on your back foot to push yourself onto the dock, has an equal end opposite amount of force going the other way from your sole of your foot, which pushes the boat the other way.

The same principle applies when you fire a cannon - in the pirate films, you see the body of the cannon forced back as it is fired.

Take it one step further, Henry VIII flagship, “Mary Rose fired all its cannons together one day in a broad side, the opposite force rolled the ship over and sank it.

Answer:

dissociation of acetic acid (like vinegar) in water

Explanation:

CH3COOH is basically vinegar (aka acetic acid)

dissociation of acetic acid in water

so when you put vinegar in water it makes 2 hydrogen ions (H+) and acetate ( CH3C00 ) a chemical that used in making film

Explanation:

he is very keen on taking up and is the age

Answer:

An intangible force that attracts objects to each other The weight of the Earth is what holds you on the ground and causes objects to fall.

Explanation:

Explanation:

I would describe it as a force that keeps Earth from floating away and keep us humans and other objects on earth's surface.

Answer:

CaCl2

Explanation:

Answer:

its a! the answer is a

Explanation:

Answer:

[tex]\frac{n}{t} = 30\ photons/s[/tex]

Explanation:

The radiated power can be given in terms of the wavelength as follows:

[tex]Rasiated\ Power = \frac{nE}{t} = \frac{nhc}{\lambda t}[/tex]

where,

Radiated Power = 1.2 x 10⁻¹⁷ W

n = no. of photons = ?

h = plank's constant = 6.625 x 10⁻³⁴ J.s

c = speed of light = 3 x 10⁸ m/s

λ = wavelength = 500 nm = 5 x 10⁻⁷ m

t = time

Therefore,

[tex]1.2\ x\ 10^{-17}\ W = \frac{n(6.625\ x\ 10^{-34}\ J.s)(3\ x\ 10^8\ m/s)}{(5\ x\ 10^{-7}\ m)(t) }\\\\\frac{n}{t} = \frac{1.2\ x\ 10^{-17}\ W}{3.975\ x\ 10^{-19}\ J}\\\\\frac{n}{t} = 30\ photons/s[/tex]

Answer:

4

Explanation:

Not all plants can grow flowers. Only the ones thay have buds can.

Not all plants produce flowers. Hence, this is the characteristic which is not common in all plants.Therefore, the correct option is 4.

Flowers are the structures of plants. They are responsible for producing seeds that will grow into new plants. Flowers typically consist of a colorful or ornamental part called the corolla, which attracts pollinators such as bees and butterflies, and a reproductive part called the stamen and pistil, which contain the plant's male and female organs.

Not all green plants produce flowers. Flowering plants are a type of plant that belong to the group Angiosperms, but there are also non-flowering plants like ferns and mosses that do not produce flowers. Therefore, the correct option is 4.

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Automation:

1. The creation and application of technology to monitor and control the production and delivery of products and services.

2. The use of machines and technology to make processes run on their own without manpower.

Examples to make you understand better:

Automations are in Meetings, Hiring Process, Employee Analytics.

Quote:

"In manufacturing, a system or method in which many or all of the processes of production, movement, and inspection of parts and materials are automatically performed or controlled by self-operating machinery, electronic devices, etc."

Fulcrum:

Picture Included.

1. The support about which a lever turns

2.The support or point of support on which a lever turns in raising or moving something

Consumerism:

Quote:

"Consumerism has a good and bad side. Although consumerism drives economic growth and boosts innovation, it comes with a fair share of problems ranging from environmental and moral degradation to higher debt levels and mental health problems."

Definition:

1. "The growth of consumerism has led to many organizations improving their service to the customer"

2. Spending money and consuming goods is good for the economy.

3. The protection or promotion of the interests of consumers.

I hope this helped!+*♡

Explanation:

Light passes from air into water at an angle of incidence of 42.3∘.42.3∘. Determine the angle of refraction in the water.

Answer:

360J

Explanation:

In physics, the kinetic energy of an object is the energy that it possesses due to its motion. It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. Having gained this energy during its acceleration, the body maintains this kinetic energy unless its speed changes. The same amount of work is done by the body when decelerating from its current speed to a state of rest.

Answer:

Just like a chemical reaction.

Answer:

New force = 9(initial force)

Explanation:

The force between two charges is given by :

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

Where

d is the original distance

Let d' is the new distance such that, r' = r/3

New force,

[tex]F'=\dfrac{kq_1q_2}{r'^2}\\\\F'=\dfrac{kq_1q_2}{(\dfrac{r}{3})^2}\\\\F'=9\times \dfrac{kq_1q_2}{r^2}\\\\F'=9F[/tex]

So, the new force becomes 9 times the initial force.

Answer:

hi how are you

2) 5/8

4) 5/8

Answer:

i'm sorry i'm not a physics student

Answer:

thread

Explanation:n general, a screw can hold 80-100 pounds. Several factors can impact on the amount of weight the screw can hold. This includes the length of the screw, the type of thread, the quality of the screw, the way it was inserted, and the type of forces that will be acting on it.

Answer:

0.16 A

Explanation:

V = IRtotal

24V = I(100 + 40 + 10)

I = 0.16 A

Answer: 0.16 is correct

Explanation:

Answer:

The distance the car moves after all ten cannonballs have been fired is 1.5 meters  

Explanation:

The parameters given in the question are;

The length of the car = 20 meters

The mass of the of the cannon ball, m₁ = 2,000 kg

The direction the cannon fires = The right

The direction the car recoils = The left

The mass of each cannonball, m₂ = 15 kg

The number of cannonballs = 10

Let v₁ represent the speed of the car and let v₂ represent the speed of the cannonball, where momentum is conserved, we have;

m₁·v₁ = m₂·v₂

2000 × v₁ = 15 × v₂

400·v₁ = 3·v₂

Therefore, when the cannon ball travels 400 meters, the railroad car travels 3 meters

Similarly, when the cannon ball travels 400/20 = 20 meters, the distance the railroad car travels, d = 3/20 meters

We not that the railroad car and the car are brought to a stop each time the cannonball hits the watt

Therefore, the total distance moved by the car after all ten have been fired, [tex]d_{total}[/tex], is given as follows;

[tex]d_{total}[/tex] = d × The number of balls fired

∴ [tex]d_{total}[/tex] = 3/20 meters per ball × 10 balls = 3/2 meters = 1.5 meters

The total distance moved by the car, [tex]d_{total}[/tex] = How far the car moves after all ten have been fired = 1.5 meters.

Answer:A - a pond has only produced a small amount of algae, so the fish population is also small. i’m pretty sure that’s correct.

Explanation: The amount of alage determines the size,or carrying capasity of the fish population,so it is a limiting factor.

Hope I could help!Brainlist?plz

Answer:

Your answer is C~

Explanation:

Answer:

It is true that Smaller the surface area greater the gravitational force and vice versa

Explanation:

The gravitational force depends on the distance between the two objects

F=GMm/r2

where G = gravitational constant

M = mass of one object

m = mass of second object

r is the distance between the two objects

Gravitational force is inversely proportional to the square of the distance between two objects. Hence, it can be said the Gravitational force is inversely proportional to the area and hence as the area increases gravitational force will decrease or vice versa

Answer: The conditions would probably exist the drew point and dry bulb temperatures to be the same at the ground because When the dew point temperature and air temperature are equal, the air is said to be saturated. Dew point temperature is NEVER GREATER than the air temperature. Therefore, if the air cools, moisture must be removed from the air and this is accomplished through condensation.

Explanation:

Since the air is said to be saturated when the dew point temperature and air temperatures are equal, the circumstances are likely present for the dew point and dry bulb temperatures to be equal at the ground. NEVER is the dew point temperature higher than that of the air temperature. As a result, condensation is used to remove moisture from the air when it cools.

The dew point, under the assumption of constant air pressure and water content, is the temperature at which air must be chilled to become water vapor condenses. Airborne vapor will condense to create liquid water, known as dew, when it is cooled below the dew point, thereby moisture capacity.  If this occurs via coming into contact with a cooler surface, dew will grow there.

Humidity influences the dew point. The dew point rises as the amount of moisture in the atmosphere increases.

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Explanation:

part 1.

s=60m

t=5s

v=s/t. =60/5 =12m/s

part 2

total s= 540+60. =600m

v=12m/s

t=s/v. =600/12 =50s