what is the main difference between a substance going through a physical change and one going through a chemical ?

Answers

Answer 1

Answer: Physical changes only change the appearance of a substance, not its chemical composition. Chemical changes cause a substance to change into an entirely substance with a new chemical formula. Chemical changes are also known as chemical reactions.

Answer 2

Answer:

just give the other person brainlyest

Explanation:


Related Questions

A car takes 9 m to stop after the driver applies the brakes.

The brakes exert a force of 2000 N.

Calculate how much work is done by this force.

Answers

Depends upon how soon you want to stop. You know the mass of the car, you know the initial velocity of 8.9 m/s. You know the final velocity which is zero. You can now calculate the deceleration of the car if you know how soon you want to stop.

Let's say you want to stop in one second.

a = (vf - vi) / t = - 8.9 m/s^2 (negative sign indicates deceleration).

F = ma = 800 x 8.9 = 7120 Newtons (kg*m/s^2)

how much work is done when a 30 kg mass is to be lifted through a height 6m?(1kg=9.8N​

Answers

we know 1kg=9.8N​ so 30 kg= 30 x 9.8 = 294 N

work is done when a 30 kg mass is to be lifted through a height 6m :

A = 294 x 6 = 1764 J

ok done. Thank to me :>

A bus is moving at a speed of 45 km/h. What is the speed of
the bus in m/s?
a) 1.25×101 m/s
b) 1.5×103 m/s
c) 2.5 m/s
d) 1.5×102 m/s

Answers

.

We want to convert the speed of the bus from kilometers per hour to meters per second.

To do this, multiply the speed in km/hr by 1,000 and divide by 3,600.

The formula to do this is: 1 km/hr = 1,000/3,600 m/s

Therefore, we have that 45 km/hr is:

45 x 1000/ 3,600 ➡️ 12.5 m/s = 1.25 x 10 to the 1st power m/s

The answer is option A.

How is the resultant displacement affected when two displacement vectors are added in a different order

Answers

Answer: it is not affected what so ever.

Explanation It will still produce the same resultant.

Identify each of the following statements related to universal gravitation as either true or false. False The gravitational field around a planet is oriented radially outward. True Stars must be at least 2 or 3 times more massive than our sun in order to become a black hole. False Orbiting astronauts are weightless because of the absence of a support force. False The outer planets in our solar system wobble in their orbits because the gravitational effects of the sun are so small. False The earth is falling toward the sun. False As you move farther from the earth, its gravitational force acting on you increases.

Answers

The characteristics of the universal gravitation law allow finding the results for which statements are true:

    2. Real stars must be at least 2 to 3 times more massive than our sun to become a black hole.

All the others are false.

The universal gravitational law states that the gravitational force is always attractive and is proportional to the masses and inversely proportional to the square of the distance.

       [tex]F = - G \frac{Mm}{r^2}[/tex]

Where F is the force, G is the universal gravitational constant, M and m are the masses and r the distance between the bodies.

Let's analyze the expressions:

1. The gravitational field around a planet is oriented radically outward

False. The force is attractive therefore it is directed towards the center of the planet.

2. Real stars must be at least 2 to 3 times more massive than our sun to become a black hole.

True. From observations of super-novae the minimum mass is 3 solar masses.

3. Astronauts in orbit are weightless due to the absence of a supporting force.

False. Astronauts have no weight because the force of gravity binds to change the direction of their velocity.

4. The outer planets of our solar system wobble in their orbits because the gravitational effects of the sun are very small.

False. The attraction of the sun decreases with the square of the distance, but the wobble is due to the attraction of the other large planets in this area.

5. The earth falls towards the sun.

False. The earth has a speed parallel to the orbit around the sun and the acceleration due to the attraction of the sun changes the direction of the orbital velocity, but the earth is not directed at the sun.

6, As you move away from the ground, the gravitational force acting on you increases.

False. The gravitational force is inversely proportional to the distance, therefore it decreases when leaving the earth.

In conclusion with the characteristics of the universal gravitation law we can find which statements are true:

     2. Real stars must be at least 2 to 3 times more massive than our sun to become a black hole.

All the others are false.

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A rock on the moon has 0.5kg. It is brought to Earth where the gravitational field is stronger. On Earth, the rock will have:
a) Less mass and same weight
b) The same mass and more weight
c) Less mass and less weight
d) The same mass and same weight

Answers

Answer:

Explanation:

It will be B.

The correct answer is the same mass and less weight.

What happens to the weight of an object when it is brought from the moon to the Earth?

The weight decreases. Your weight will be 1/6 of the weight on the moon that you had on Earth. This is because the mass of the moon is less hence the gravitational pull is very low compared to Earth.

What happens to the mass of an object when you take it to the moon?

Therefore, the mass of an object on the Moon remains the same as its mass on Earth. But its weight gets less because the gravity on the moon is less than on the Earth.

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The initial temperature of the mixture was +20 °C. The mixture froze at -1.5 °C.
A total of 165 kJ of internal energy was transferred from the mixture to cool and
freeze it.
specific heat capacity of the mixture = 3500 J/kg °C
specific latent heat of fusion of the mixture = 255 000 J/kg
Calculate the mass of the mixture.
Give your answer to 2 significant figures.
[6
M

Answers

Answe16000/3500(-1.5-2-)225000= 1.1

Explanation:

The mass of the mixture will be 2.19 ×10⁻³ kg. The unit of mass is kg and it is a scalar quantity.

What is mass?

Mass is a numerical measure of inertia, which is a basic feature of all matter. It is, in effect, a body of matter's resistance to a change in speed or position caused by the application of a force.

In the International System of Units (SI), the kilogram is the unit of mass.

The given data in the problem is;

The initial temperature of the mixture was, [tex]\rm T_i = 20 ^0 \ C[/tex]

The mixture froze at the temperature of, [tex]\rm T_F = -1.5 ^0 \ C[/tex]

The internal energy is,[tex]\rm E = \rm 165 \ kJ[/tex]

The specific heat capacity of the mixture is,[tex]\rm C = 3500 J/kg ^0C[/tex]

The specific latent heat of fusion of the mixture is,[tex]\rm l = 255 000 J/kg[/tex]

m is the mass of the mixture,

The latent heat is equal to the heat transfer. Because the net work done is zero.

The formula for the heat transfer is found as;

[tex]\rm Q = mCdt \\\\ m = \frac{Q}{Cdt} \\\\ m = \frac{165 }{3500(20-(-1.5)} \\\\ m = 2.19 \times 10^{-3} \ kg[/tex]

Hence the mass of the mixture will be 2.19 ×10⁻³ kg.

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You have a particle of length 68 nm. What is this in meters?
A. 6.8 x 10^10 m
B. 6.8 x 10^14 m
C. 6.8 x 10^-11 m
D. 6.8 x 10^-8 m

The number after "^" that symbol are exponents ​

Answers

A. 6.8 x 10^10 m

Don’t pay attention to this part

how does the hypothesis of inflation account for the existence of the seed of density from which galaxies and other large structures formed

Answers

Inflation would have caused random, microscopic quantum fluctuations to grow so large in size that they became the seeds of structure.

Mushroom is a fungi. ​

Answers

[tex]⇒[/tex]

Mushrooms are filamentous fungi that produce large, often edible fruiting bodies. They live on organic material, thriving on compost, fallen leaves and damp wood and any other dead plant or animal matter. Their role in causing decay is important in maintaining ecological cycles.

Ryan and his dad go paintball img they 700 balls each how much did paintballing cost for the two of them

Answers

Answer:

We don't know how much it cost bc u didn't give us a number of how much one person cost or any details but if you add both of the balls together they have 1,400 balls

To calculate the cost of paintballing for Ryan and his dad, we need to know the cost per paintball. Once we have that information, we can multiply it by the total number of paintballs they used (700 balls each).

Let's say the cost per paintball is $0.50.

For Ryan:

Cost for Ryan = Cost per paintball × Number of paintballs used by Ryan

Cost for Ryan = $0.50/ball × 700 balls = $350

For his dad:

Cost for Dad = Cost per paintball × Number of paintballs used by Dad

Cost for Dad = $0.50/ball × 700 balls = $350

Total cost for both of them:

Total Cost = Cost for Ryan + Cost for Dad

Total Cost = $350 + $350 = $700

So, the total cost of paintballing for Ryan and his dad is $700, assuming the cost per paintball is $0.50.

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what is the fate of the energy in ultraviolet light that is incident upon glass?

Answers

Answer:

we can say when UV light is incident. Essentially, when it strikes glass or incident upon gloss, it will be absorbed. The energy has to go somewhere. Um, and in this case, this radiation is then converted to thermal energy and the glass raises and temperature.

Explanation:

Got the information from the internet

HELP PLZZZZZZ
A 30 g spoon is lifted above a table and has 0.062 J of potential energy. How high is it?

Answers

Hi there!

We know that:

U (Potential energy) = mgh

We are given the potential energy, so we can rearrange to solve for h (height):

U/mg = h

g = 9.81 m/s²

m = 30 g ⇒ 0.03 kg

0.062/(0.03 · 9.81) = 0.211 m

Glucose typically enters the cell through which mechanisms

Answers

Answer:

facilitated diffusion

A tellurium-sapphire laser can produce light at wavelength of 800 nm in ultrashort pulses that last only 4.00x10-15s (4.00 femtoseconds, or 4.00 fs). The energy in a single pulse produced by one such laser is 2.00 μJ = 2.00x10-6 J, and the pulses propagate in the positive x-direction. Find a) the frequency of the light; b) the energy and minimum energy uncertainty of a single photon in the pulse

Answers

The speed of light and the propagation of errors allows to find the results on the questions of the radiation emitted by the laser are:

    a) The frequency is: f = 3.7 10¹⁴ Hz

    b) The energy with its uncertainty is: E = (2.465 ± 0.004) 10⁻¹⁹ J

a) The speed of a wave is related to its wavelength and frequency.

           c = λ f

           [tex]f = \frac{c}{\lambda}[/tex]

Where c is the speed of light, λ the wavelength and f the frequency.

They indicate that the wavelength is λ = 800 nm = 800 10⁻⁹ m, the speed of light is a constant c = 2.99 10⁸ m/s.

         f = [tex]\frac{2.99 \ 10^8}{800 \ 10^{-9}}[/tex]  

         F = 3.7 10¹⁴ Hz

b) Planck's equation states that the energy is proportional to the frequency of the radiation.

         E = h f

Where E is the energy, h the Planck constant and f the frequency.

         E = 6.63 10⁻³⁴  3.7 10¹⁴

         E = 2.46467 10⁻¹⁹ J

The uncertainty or error is the fluctuation that a magnitude may have due to the precision in the measurements, when the magnitude is calculated by some formula, the propagation of these uncertainties must be carried out.

         

        Δm = ∑   [tex]\sum \frac{dm}{dx_i} | \Delta x_I|[/tex]  

the expression for energy is:

        E = [tex]\frac{hc}{\lambda }[/tex]  

        [tex]\Delta E = \frac{dE}{d \lambda} |D\lambda |[/tex]  

        [tex]\Delta E = \frac{h c }{\lambda^2 } |\Delta \lambda |[/tex]

When the error in the measured magnitude is not explicitly indicated, we assume that the error is in the last digit written, therefore

         Δλ = ± 1 nm = ± 1 10⁻⁹ m

We calculate.

        [tex]\Delta E = \frac{6.63 \ 10^{-34} \ 2.99 \ 10^8 }{(800 \ 10^{-9})^2} 1 \ 10^{-9}[/tex]  

        ΔE = 3.1 10⁻²² J

the error is given with a significant figure.

        ΔE = 3 10⁻²² J = 0.004 10⁻¹⁹ J

The result of the energy is:

        E = (2.465 ± 0.004) 10⁻¹⁹ J

In conclusion, using the speed of light and the propagation of errors, we can find the results on the questions of the radiation emitted by the laser are:

    a) The frequency is; f = 3.7 1014 Hz

    b) The energy with its uncertainty is: E = (2.465 ± 0.004) 10⁻¹⁹ J

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John carries a 5 kg bag horizontally to the checkout line. How much work must he
do to move it 8 m at a constant velocity of 1 m/s to the right?

Answers

The work John must do to move the bad horizontally to given distance is 2.5 J.

The given parameters;

mass of the  bag, m = 5 kgdistance moved by the bad, d = 8 mvelocity of bag, v = 1 m/s

The acceleration of the bag at the given distance and velocity is calculated as follows;

[tex]v^2 = u^2 + 2as\\\\1^2 = 0 + 2(a)(8)\\\\1 = 16 a\\\\a = \frac{1}{16} \\\\a = 0.0625 \ m/s^2[/tex]

The work done in moving the bag to 8m is calculated as follows;

[tex]W = F \times d\\\\W = ma \times d\\\\W = 5 \times 0.0625 \times 8 \\\\W = 2.5 \ J[/tex]

Thus, the work John must do to move the bad horizontally to given distance is 2.5 J.

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A measuring cylinder contains 80 cm3 of a certain liquid. The liquid is poured

into an empty beaker of mass 48 g. The total mass of the beaker and the liquid

was found to be 136 g.

(a) Calculate the mass of the liquid in grams.

(b)Calculate the density of the liquid in gcm-3

Answers

Answer:

1.5 g/cm

3

Let d be the density of fluid.

So , Initial reading of balance, F

1

=30dg N

After the level reaches 50cm

3

Final reading of balance , F

2

=50dg N

Given that difference between final and initial reading is 30g

i.e, F

2

−F

1

=30 g

⟹50dg−30dg=30g

⟹20dg=30g

⟹d=

20g

30g

⟹d=1.5g/cm

3

So, density of fluid is 1.5g/cm

3

najah, a management researcher, conducted an experiment with the goal of confirming or contradicting the behavioral leadership approach. najah spent many days following managers around while they worked. like the ohio state university and university of michigan studies, najah’s data showed that most managers focus on

Answers

Based on the information that is depicted from the question, the data from Najah showed that most managers focus on consideration and inspiration.

The behavioral leadership theory simply focuses on how leaders behave. The theory also assumes that other leaders copy each other's traits.

Based on the complete information, the data illustrated that most managers focus on consideration and inspiration. Managers inspire their subordinates in order to accomplish a goal.

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which of these MANNER of death? (select all that apply)
1-blood loss
2-cessation of brain function
3-accidential death
4-stabbing
5-pulmonary arrest
6-homicidal death
7-natural death
8-shooting

Answers

Answer:

3, 4, 6, 7, 8 are manners of death.

the schwarzschild radius of a black hole depends on

Answers

Answer:

The mass of the object.

Explanation:

Happy Thanksgiving!

The Schwarzschild radius of a black hole depends solely on its mass. The Schwarzschild radius is a concept in general relativity that defines the boundary known as the event horizon.

The formula for the Schwarzschild radius is given by:

r_s = 2GM / c²

Where: r_s is the Schwarzschild radius

As the mass of the black hole increases, its Schwarzschild radius also increases. This means that a more massive black hole has a larger event horizon and a stronger gravitational pull.

The mass of the black hole is the primary factor determining the size of the Schwarzschild radius, while other properties, such as spin or charge, can also affect the structure and behavior of the black hole but do not directly impact the Schwarzschild radius.

Therefore,The Schwarzschild radius of a black hole depends solely on its mass.

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Compare and contrast instantaneous and average speed.

Answers

Answer:

instantaneous velocity is a velocity covered at an instant while average velocity is the change in distance/ the change in time taken

what is use of hydraulic machine?​

Answers

Answer:

Hydraulic machines use liquid fluid power to perform work. Heavy construction vehicles are a common example.

Explanation:

In this type of machine, hydraulic fluid is pumped to various hydraulic motors and hydraulic cylinders throughout the machine and becomes pressurized according to the resistance present.

Hope it helps and welcome :)

Brainliest plsss thank you :)

In an experiment to determine the density of a substance the following results were
obtained. Use the results to plot a graph of mass against volume.
Mass (g) 10 20 30 40 50 60 70 80 90
Volume (cm 3 ) 0.5 1.0 1.4 2.0 2.2 2.6 3.0 3.6 4.5

a) Find the gradient of the graph.
b) What does the gradient represent?
c) What is the mass when the volume is 1.5cm 3 ?
d) What is the volume when the mass is 65g?

Answers

Answer:

a) Gradient = rise/run = mass/volume

since the graph is mass against volume we know mass is on the y-axis and volume is on the x-axis

in physics it’s best to use a larger part of the graph to find the gradient, so imma use the biggest values.

90/4.5 = 20

(additional note: sometimes you may get a different gradient. For example, when using 30 and 1.4 you get ≈21 this is an anomalous result since ita gradient differs; a mass against volume graph is supposed to be linear)

b) gradient represents density (p) since gradient is = mass/volume. And density also = mass/volume

For c and d just plot the points and you’ll be able to read from the graph to get the values.

I got this graph (the image)

but you’ll be able to interpret better when ‘you’ draw it (so try plotting it)

A young woman walks up 55 steps to the top of a water slide. She slides
down, feet first, all the way to the bottom gaining speed as she goes. If each
step of the slide is.10m tall, how fast will she be going at the bottom?

Answers

Answer:

potential energy PE = M g h

KE at bottom = 1/2 M V^2

Regardless of the slope of the slide the change in energy is the same

1/2 V^2 = g h

V = (2 g h)^1/2 = (2 * 9.8 m/s^2 * 10 m)^1/2 = 14 m / s

Perhaps the question says that h = 55 * .1 = 5.5 m

Then V = (2 * 9.8 * 5.5) = 10.4 m/s

Please help...
Will give the brainliest !!!
Please answer correctly

Answers

5) a) An alpha particle consists of 4 nucleons. Two of these are protons and two are neutrons.  An alpha particle carries a charge of +2 (due to the particles having 2 protons).

b)  A beta minus particle is a fast moving electron that's emitted from the nucleus. It's created when neutrons in the nucleus decays to form a proton & the beta particle.

c) A 3rd type of ionising radiation has no mass. It's called gamma radiation (gamma rays / X - rays). This type of radiation is a type of wave with a very short / low wavelength.  (shortest wavelength among others)

d) Gamma radiation is a part of the electromagnetic spectrum.

_______

Hope it helps ⚜

Which statement describes the flow of heat? Question 8 options: Heat moves from a warmer object to a cooler object. Heat moves from a cooler object to a warmer object. Heat moves from a cooler object to a warmer object. Heat moves only between two cold objects.

Answers

Answer:

A

Explanation:

as shown in the figure, a 10-kg block on a perfectly smooth horizontal table is connected by a horizontal string to a 63-kg block that is hanging over the edge of the table. what is the magnitude of the acceleration of the 10-kg block when the other block is gently released?

Answers

Newton's second law allows to find the acceleration of the two-body system, where a mass is hanging is:

The acceleration of the system is: a = 8.46 m / s²

Newton's second law states that the net force on a body is equal to the product of the mass and the acceleration.

         ∑ F = m a

Where the bold letters indicate vectors, F is the force, m the mass and the acceleration of the body.

A free body diagram is that diagram of the system where the forces are shown without the details of the bodies. In the attachment we have a free-body diagram of the system.

Let's write Newton's second law for each axis.

x- axis

        T = m₁ a

y-axis

body in the horizontal part

        N-W₁ = 0

       N = W₁

Body hanging.  

         W₂ - T = m₂ a

Wwhere the positive direction is down, let's write our system of equations.

         

                T = m₁ a  

         W₂-T = m₂ a

Let's Resolve.

          m₂ g = (m₁ + m₂) a

          a = [tex]\frac{m_2}{m_1+m_2} \ g[/tex]  

Let's calculate.

         a =[tex]\frac{63}{10+63} \ 9.8[/tex]  

         a = 8.46 m / s²

In conclusion using Newton's second law we can find the acceleration of the two-body system, where a mass is hanging is:

The acceleration of the system is: a = 8.46 m / s²

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A rock excerts a pressure of 20 N/cm^2 on the ground. what does 20N/cm^2 mean?

A force of __________ acts on each _________ of area​

Answers

Answer:

A force of 20N acts on each cm^2 of area

If the coefficient of kinetic friction between the puck and the ice is 0.05, how far does the puck slide before coming to rest? Solve this problem using conservation of energy. initial speed is 5.3 m/s

Answers

Hi there!

We know that:

Ei = Ef

There is work being done on the object, so:

W = Force · displacement = F · d ⇒ work due to friction

KEi - Fd = KEf (0)

KEi = Fd

Input variables:

1/2mv² = μmgd

Cancel out the mass:

1/2v² = μgd

Solve for d:

1/2(5.3²)/(0.05 · 9.81) = 28.63 m

Which of the following, if eliminated, would completely prevent the greenhouse effect from occurring on earth?

A. Atmosphere Clouds

B. Fossil fuels

C. Acid rain

D. The ozone layer

E. Chlorofluorocarbons​

Answers

I think answer correct A ……………

Chlorofluorocarbons​ is eliminated, would completely prevent the greenhouse effect from occurring on earth.

What is greenhouse effect?

The greenhouse effect is a phenomenon in which heat from a planet's host star passes through its atmosphere and warms the surface of the planet, but greenhouse gases in the atmosphere prevent part of the heat from going directly to space, making the world warmer.

Chlorofluorocarbons gas is main cause of greenhouse effect so when we remove it from atmosphere than green house effect will be reduced.

Chlorofluorocarbons​ is eliminated, would completely prevent the greenhouse effect from occurring on earth.

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