When dry ice appears to be smoking what is actually happening

Answers

Answer 1

Answer:

The “smoke” coming from dry ice is actually carbon dioxide gas, which is turning from a solid into a gas.

Explanation:


Related Questions

Which sentence accurately uses the homophones “they’re,” “there,” or “their”?

Many of the students left there backpacks on the bus.
They’re going to come home as soon as the movie is over.
I think I left the bags of groceries on the floor over their.
These dogs bark at everyone, but there not dangerous at all.

Answers

Answer:

They're going to come home as soon as the movie is over.

Answer:

B: They're going to come home as soon as the movie is over.

Explanation:

1. Describe the components of the reflex arc

Answers

The simplest arrangement of a reflex arc consists of the receptor, an interneuron (or adjustor), and an effector; together, these units form a functional group. Sensory cells carry input from the receptor (afferent impulses) to a central interneuron, which makes contact with a motor neuron.

Katelyn (55 kg) is practicing a drop jump in the biomechanics lab. She steps off a plyometrics box, lands on the force plate, and immediately jumps back up into the air. Right before she hits the force plate, her vertical velocity is 3.0 m/s downwards. After leaving the ground again, her vertical velocity is 3.5 m/s upwards. Katelyn was in contact with the ground for 0.4 seconds. (a) What was the impulse exerted on Katelyn when she was on the force plate

Answers

Answer:

J = 357.5 kg*m/s

Explanation:

The impulse exerted on Katelyn when she was on the force plate, is equal to the change in her momentum, according to Newton's 2nd Law.Assuming as the positive direction the upward direction (coincident with the positive y-axis) we can express the initial momentum as follows:

       [tex]p_{o} = m*v_{o} = 55 kg * (-3.0 m/s) (1)[/tex]

By the same token, the final momentum is as follows:

       [tex]p_{f} = m*v_{f} = 55 kg * (3.5 m/s) (2)[/tex]

As we have already said, the impulse J is just equal to the change in momentum, i.e., the difference between (2) and (1):

      [tex]J = p_{f} - p_{o} = m* (v_{f} -v_{o}) = 55 kg* (3.5m/s- (-3.0m/s)) = 357.5 kg*m/s (3)[/tex]

Which of the following is NOT true about a space-based internet system? * Data is transmitted in the form of electromagnetic radiation. Signals travel faster through space than through fiber-optic cables. No ground equipment is needed to access the internet. The network is made of many satellites organized in a grid pattern

Answers

Answer:

A Data is transmitted in the form of electromagnetic radiation.

B Signals travel faster through space than through fiber-optic cables.

C No ground equipment is needed to access the internet.

D The network is made of many satellites organized in a grid pattern.

Explanation:

THose are the options

Answer:

B

Explanation:

Which of the following best
describes amplitude?
A. Amplitude is how fast a wave travels.
B. Amplitude is how far a wave moves from its resting
position
C. Amplitude is the resting position of a wave.

Answers

Answer:

its b

Explanation:

Amplitude, in physics, the maximum displacement or distance moved by a point on a vibrating body or wave measured from its equilibrium position. It is equal to one-half the length of the vibration path.

The answer Is A Hope this helps

A capacitor with an initial potential difference of 100 V is discharged through a resistor when a switch between them is closed at t 0.At t 10.0 s, the potential difference across the capacitor is 1.00 V. (a) What is the time constant of the circuit

Answers

Answer:

τ = RC = 2.17 s

Explanation:

The voltage through a capacitor can't change instantaneously, so immediately after the switch is closed, the potential difference will keep at 100 V.This voltage will produce a flow of charge (a current) from the capacitor to the resistor, which will be diminishing continuously, till the capacitor be totally discharged, and the current becomes zero.The voltage through the capacitor will follow an exponential function of time, as follows:

       [tex]V_{C} =V_{o} * e^{-t/RC} (1)[/tex]

Replacing by the givens in (1):

       [tex]V_{C} = 1.00 V\\V_{o} = 100V\\t = 10.0 s[/tex]

      [tex]\frac{1.00V}{100 V} = e^{-10s/RC} (2)[/tex]

Taking ln on both sides in (2), and solving for RC, we have:

       [tex]R*C= \frac{-10s}{ln 0.01} = 2.17s (3)[/tex]

So, the time constant of the circuit (the product of R times C) is equal to 2.17s.

An astronomer studies an image taken by a satellite in space and sees an area of gas, dust, and many stars distributed along spiral arms. What is the astronomer most likely seeing?

Answers

Answer:the answer is galaxy

Explanation:

The basal metabolic rate is the rate at which energy is produced in the body when a person is at rest. A 75-kg (165-lb) person of height 1.83 m (6 ft) has a body surface area of approximately 2.0 m2. (a) What is the net amount of heat this person could radiate per second into a room at 18°C (about 65°F) if his skin’s surface temperature is 30°C? (At such temperatures, nearly all the heat is infrared radiation, for which the body’s emissivity is 1.0, regardless of the amount of pigment.) (b) Normally, 80% of the energy produced by metabolism goes into heat, while the rest goes into things like pumping blood and repairing cells. Also normally, a person at rest can get rid of this excess heat just through radiation. Use your answer to part (a) to find this person’s basal metabolic rate.

Answers

Answer:

(a) Q = 142.67 W

(b) Basal Metabolic Rate = 178.33 W

Explanation:

(a)

We can find the heat radiated by the person by using Stefan-Boltzman's law:

[tex]Q = \sigma A (T^4 - T_{s}^4)\\[/tex]

where,

Q = heat radiated per second = ?

σ = Stefan-Boltzman Constant = 5.6703 x 10⁻⁸ W/m².k⁴

A = Surface Area = 2 m²

T = Temperature of Skin = 30° C + 273 = 303 k

Ts = Temperature of room = 18° C +273 = 291 k

Therefore,

[tex]Q = (5.6703\ x\ 10^{-8}\ W/m^2.k^4)(2\ m^2)[(303\ k)^4-(291\ k)^4][/tex]

Q = 142.67 W

(b)

Since the heat calculated in part (a) is 80 percent of basal metabolic rate. Therefore,

[tex]Q = (0.8)(Basal\ Metabolic\ Rate)\\Basal\ Metabolic\ Rate = \frac{Q}{0.8}\\\\Basal\ Metabolic\ Rate = \frac{142.67\ W}{0.8}[/tex]

Basal Metabolic Rate = 178.33 W

(a)  The  excess heat just through radiation Q = 142.67 W

(b) Basal Metabolic Rate = 178.33 W

What is metabolic rate?

Basal metabolic rate is the number of calories your body needs to accomplish its most basic (basal) life-sustaining functions.

(a) We can find the heat radiated by the person by using Stefan-Boltzman's law:

[tex]Q=\sigma A(T^4-T_s^4)[/tex]

where,

Q = heat radiated per second = ?

σ = Stefan-Boltzman Constant = 5.6703 x 10⁻⁸ W/m².k⁴

A = Surface Area = 2 m²

T = Temperature of Skin = 30° C + 273 = 303 k

Ts = Temperature of room = 18° C +273 = 291 k

Therefore,

[tex]Q=(5.6703\times 10^{-8}\times (2)\times[(303)-(291)][/tex]

Q = 142.67 W

(b) Since the heat calculated in part (a) is 80 percent of basal metabolic rate. Therefore,

[tex]\rm Q=0.8\times (Basal\ Metabolic\ Rate)[/tex]

[tex]\rm Basal\ metabolic \ Rate = \dfrac{Q}{0.8}[/tex]

[tex]\rm Basal\ Metabolic\ Rate = \dfrac{142.67}{0.8} =178.330W[/tex]

Basal Metabolic Rate = 178.33 W

Hence the  excess heat just through radiation Q = 142.67 and Basal Metabolic Rate = 178.33 W

To know more about Basal metabolic rate Follow

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While being thrown, a net force of 132 N acts on a baseball (mass = 140g) for a period of 4.5 x 10^-2 sec. what is the magnitude of the change in momentum of the ball?

Answers

Answer:

5.94 N·s

Explanation:

F = 132 N

t = 0.045 s

Impulse = Ft = (132 N)(0.045 s) = 5.94 N·s

an ice skater is moving across a flat and level skating rink and is speeding up. which one of the following statement is true of the ice skater

a) its potential energy is constant
b) its potential energy is increasing
c) its potential energy is decreasing​

Answers

Answer:

A

Explanation:

The angular momentum of a system of particles around a point in a fixed inertial reference frame is conserved if there is no net external torque around that point:

d

L

d

t

=

0

or

L

=

l

1

+

l

2

+

+

l

N

=

constant

.

Note that the total angular momentum

L

is conserved. Any of the individual angular momenta can change as long as their sum remains constant. This law is analogous to linear momentum being conserved when the external force on a system is zero.

A satellite, moving in an elliptical orbit, is 368 km above Earth's surface at its farthest point and 164 km above at its closest point. (a) Calculate the semimajor axis of the orbit. Incorrect: Your answer is incorrect. m (b) Calculate the eccentricity of the orbit. Incorrect: Your answer is incorrect. Did you find the semimajor axis a from the greatest and smallest radii

Answers

Answer:

a) 6636 km

b) 0.0154

Explanation:

The height above the earth at its furthest point is 368 km

The height above the earth at its closest point is 164 km

Radius of the Earth is 6370 km

The distance of the satellite from the center of the earth to the furthest point is 6370 + 368 km = 6738 km

The distance of the satellite from the center of the earth to the closest point is 6370 + 164 = 6534 km

If we add together the sum of the distance of the satellite from the furthest and its closest distance, it is equal to the 2 major semi axis.

Basically,

2a = R + r

a = (R + r) / 2

a = (6738 + 6534) / 2

a = 13272 / 2

a = 6636 km

Eccentricity, e = (a - r) / a

Eccentricity, e = (6636 - 6534) / 6636

Eccentricity, e = 102 / 6636

Eccentricity, e = 0.0154

Calculate the average maximum height for all three trials when the mass of the bottle is 0.125 kg, 0.250 kg,
0.375 kg, and 0.500 kg.

Record your calculations in Table A of your Student Guide.

When the mass of the bottle is 0.125 kg, the average maximum height of the beanbag is
m.

When the mass of the bottle is 0.250 kg, the average maximum height of the beanbag is
m.

When the mass of the bottle is 0.375 kg, the average maximum height of the beanbag is
m.

When the mass of the bottle is 0.500 kg, the average maximum height of the beanbag is
m.

Answers

Answer:

10

Explanation:

i dont know this is right answer

0.35

0.91

1.26

1.57

Explanation:

I did it on ed2020 and got it correct

16. Two capacitors have an equivalent
capacitance of 30 pF, if connected in
parallel, and 7.2 pF, if connected in
series. Find C1 and C2.​

Answers

Answer:

C1 + C2 = 30     parallel connection

C1 * C2 / (C1 + C2) = 7.2  series connection

C1 * C2 = 7.2 * (C1 + C2) = 216

C2 + 216 / C2 = 30    using first equation

C2^2 + 216 = 30 C2

C2^2 - 30 C2 + 216 = 0

C2 = 12 or 18    solving the quadratic

Then C1 = 18 or 12

the equation P^xV^yT^z= constant is Boyle law for what is the values of x,y,z​

Answers

Answer:

x = 1, y = 1 and z = 0

Explanation:

Given equation;

[tex]P^x V^y T^z = constant[/tex]

Boyle's law states that at constant temperature, the volume of a fixed mass of gas is inversely proportional to its pressure.

Mathematically the law is written as;

[tex]PV = constant[/tex]

From the given equation, the values of x, y and z that will match this law is calculated as follows;

[tex]P^1 V^1 T^0 = constant\\\\P^1 = P\\\\V^1 = V\\\\T^0 = 1\\\\P \times V \times 1 = PV = constant\\\\Thus, x = 1, \ y = 1 \ \ and \ z = 0[/tex]

Which is an example of a wedge?
A.
B
C
D

Answers

Answer:

B I believe, because the axe is wedged into the log

Answer:

B

Explanation:

I think just rhis is the answer

We would like to compare the angular momentum of Mars about its axis of rotation with that of Earth's. The mass of Mars is 11% that of Earth, with a radius 53% that of Earth, and a rotational period 103% that of Earth. Assuming both planets to be uniform spheres calculate the ratio of the angular momentum of Mars to that of Earth.

Answers

Explanation:

Assume that mass of Earth is M, radius of earth orbit is R, and rotational period of Earth is T.

The angular momentum of Earth is,

 [tex]L_{z} &=M R^{2} \omega \\ &=M R^{2}\left(\frac{2 \pi}{T}\right) \\ &=\frac{2 \pi M R^{2}}{T}[/tex]

The mass of mars is, mass of Earth

=0.11 M

The radius of mars orbit is, of radius of earth

=0.53 R

The rotational period of mars is, of period of Earth

=1.03 T

The angular momentum of mars is,

[tex]L_{m}=\frac{2 \pi(0.11 M)(0.53 R)^{2}}{1.03 T}[/tex]

The angular momentum of mars is,

[tex]L_{m}=\frac{2 \pi(0.11 M)(0.53 R)^{2}}{1.03 T}[/tex]

The ratio of angular momentum of mars to that of earth is,

[tex]\frac{L_{m}}{L_{E}}=\frac{\frac{2 \pi(0.11 M)(0.53 R)^{2}}{1.03 T}}{\frac{2 \pi M R^{2}}{T}} \\ \frac{L_{m}}{L_{E}}=0.03 \\ \frac{L_{m}}{L_{B}}=3.0 \times 10^{-2}[/tex]

A marshmallow is fired from ground level with an initial speed of 41.5 m/s at an
angle of 33.5° above the horizontal. (a) Determine the maximum height reached
by the marshmallow. (b) Determine the horizontal range that the marshmallow
travels during its flight.

Answers

Look at picture first I couldn’t fit it all in but after you get the time get all the x values that you have and sub into s=ut+1/at^2

S=? t=2.34 a=0 u=41.5cos(33.5)
s= (41.5cos(33.5))(2.34)+1/2(0)
s=80.98 meters
this is the horizontal range

A force of 880 newtons stretches a spring 4 meters. A mass of 55 kilograms is attached to the end of the spring and is initially released from the equilibrium position with an upward velocity of 8 m/s. Find the equation of motion. x(t)

Answers

Answer:

x(t) = -8sin2t

Explanation:

See the attachment for solution

From my solving, we can deduce that w² = 4, and thus, w = 2

Therefore, the general solution is

x(t) = c1 cos2t + c2 sin2t

Considering the final variable, we can conclude that

x(0) = 0

x'(0) = -8 m/s

The final solution, thus

x(t) = -8sin2t

HELP ITS DUE IN 4 MINUTES

Answers

Answer:

the nephew

Explanation:

because we need to First find the trails that is on top of all the others in order to find who was the last to leave, since the person that was last to leave would most likely step on another person's trail that has been theirs before them.

by looking at this picture I noticed that the butler's footprint was the latest one but the dogs footprint steps over it therefore making it the last to leave, and the person who owns a dog is her nephew so therefore the nephew is the one that stole the butterfly trophy.

Which of the following statements is NOT correct about sea breezes?
A) In a sea breeze, the sand is much warmer than the water, therefore creating a low pressure above the sand.
B) The breeze/wind moves from the sea to the land.
C) The breeze/wind moves from the land to the sea.
D) There is high pressure above the sea, and low pressure above the sand.

Answers

I think the correct answer is B.

The breeze/wind moves from the land to the sea. This statement is NOT correct about sea breezes.

What is  sea breeze?

Local wind patterns known as sea breezes flow from the sea to land during the day. When there is no strong large-scale wind system and it is very hot or very cold during the day or at night, sea breezes and land breezes alternate along the coasts of large lakes or oceans.

Because the sea breeze's surface flow ends over land, an area of low-level air convergence is created. Locally, this convergence frequently causes air to rise, which promotes the formation of clouds. Showers over land in the afternoon may result from such clouds.

Hence, the sea  breeze/wind moves from the land to the sea. This statement is NOT correct about sea breezes.

Learn more about sea breeze here:

https://brainly.com/question/13015619

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Equal amounts of heat are added to equal masses of ice and copper at the same initial temperature. Which substance will have the higher final temperature?
ice
copper

How much greater will that temperature change be than the temperature change of the other substance?
larger ΔT/smaller ΔT
= ?

Answers

One of the major effects of heat transfer is temperature change: heating increases the temperature while cooling decreases it. We assume that there is no phase change and that no work is done on or by the system. Experiments show that the transferred heat depends on three factors—the change in temperature, the mass of the system, and the substance and phase of the substance.

Figure a shows a copper-colored cylinder of mass m and temperature change delta T. The heat Q, shown as a wavy rightward horizontal arrow, is transferred to the cylinder from the left. To the right of this image is a similar image, except that the heat transferred Q prime is twice the heat Q. The temperature change of this second cylinder, which is also labeled m, is two delta T. This cylinder is surrounded by small black wavy lines radiating outward. Figure b shows the same two cylinders as in Figure a. The left cylinder is labeled m and delta T and has a wavy heat arrow pointing at it from the left that is labeled Q. The right cylinder is labeled two m and delta T and has a wavy heat arrow pointing to it from the left labeled Q prime equals two Q. Figure c shows the same copper cylinder of mass m and with temperature change delta T, with heat Q being transferred to it. To the right of this cylinder, Q prime equals ten point eight times Q is being transferred to another cylinder filled with water whose mass and change in temperature are the same as that of the copper cylinder.

Pick 3 safety rules in science that you think are important and explain what would happen if the rules were no followed. Used your own word.

Answers

Answer:

Answer down below!

Explanation:

Always wear goggles! This is to prevent chemicals or any other substance to get into your eyes. If this wasn't followed, more people could get hurt.Clean up afterwards! Its always better to clean up so someone else couldn't get hurt! If people don't follow this, it could be a mess and someone could get seriously injured.When smelling something, waft it to your face, and not get real close. This is to prevent getting chemicals into your body that could be poisonous. If people didn't folloe this, someone could be seriously sick.

An ant crawls in a straight line at a constant speed of 0.24 m/s for a distance of 3.0 m, beginning in the corner of a square classroom. It then turns exactly 90 degrees to the right, and proceeds an additional 4.0 m, reaching the far corner of the same wall from which it began. If the second leg of the journey was crawled in half the amount of time as the first, what was the ant's average speed for the whole trip?

Answers

Answer:

vavg = 0.37 m/s

Explanation:

The average speed is just the relationship between the total distance traveled, and the total time required for that travel , as follows:

       [tex]v_{avg} = \frac{\Delta x}{\Delta t} (1)[/tex]

We know that for the first leg of the journey, the ant crawls at a constant speed of 0.24 m/s, moving 3.0 m.We can find the time required for this part, just applying the definition of average velocity, and solving for the time t (which we will call t₁), as follows:

       [tex]t_{1} =\frac{x_{1}}{v_{1} } = \frac{3.0m}{0.24m/s} = 12.5 s (2)[/tex]

From the givens, we know that the time for the second part is exactly the half of the value found in (2), so we can write the total time Δt as follows:

       [tex]\Delta t = t_{1} + \frac{t_{1} }{2} = 12.5 s + 6.25 s = 18.75 s (3)[/tex]

We also know that in the second leg of the journey, the ant traveled 4.0 m, which adds to the 3.0 m of the first part, making a total distance of 7.0 m.Per definition of average speed, we can write the following expression as in (1) replacing Δx and Δt by their values, as follows:

       [tex]v_{avg} = \frac{\Delta x}{\Delta t} = \frac{7.0m}{18.75m} = 0.37 m/s (4)[/tex]

Conductivity in aqueous solutions, is a measure of the ability of water to conduct an electric current.

a. True
b. False

Answers

Answer:

true

Explanation:

i think its true beacuse water can cause electricity

pls let me know if corrct

if yes pls mark brainlest

A 700 kg horse has 4000 J of kinetic energy as it is running
What is the velocity of the horse?

Answers

Answer:

m

Explanation:

0. What is centripetal accleration?Derive relation for it​

Answers

Answer:

Centripetal acceleration is defined as the property of the motion of an object, traversing a circular path. Any object that is moving in a circle and has an acceleration vector pointed towards the center of that circle is known as Centripetal acceleration. ... Centripetal means towards the center.

Define as property of motion

1. An electron travels 4.82 meters in 0.00360 seconds. What is its average speed?

Answers

Answer:

speed =distance /time

speed =4.82/0.00360

speed =1338.8m/s

elophase II is the final and the fourth stage in meiosis II when the chromosomes reach the opposite poles of the

Answers

Answer: The correct answer is formation of four haploid nuclei.

The event occurring during telophase II includes formation of four haploid daughter cells. Telophase II is the final and the fourth stage in meiosis II when the chromosomes reach the opposite poles of the nuclear spindle. During this stage both the daughter cells get divided forming four haploid cells. The development of the nuclear envelope around each set of the chromosome and cytokinesis also takes place during telophase II.

Explanation:

???

Experiments carried out on the television show Mythbusters determined that a magnetic field of 1000 gauss is needed to corrupt the information on a credit card's magnetic strip. (They also busted the myth that a credit card can be demagnetized by an electric eel or an eelskin wallet.) Suppose a long, straight wire carries a current of 5.0 A .
How close can a credit card be held to this wire without damaging its magnetic strip?

Answers

Answer:

his distance is too small (r = 0.01 mm), therefore the cut can be at any distance

Explanation:

For this exercise let's use the ampere law.

Let's use a cylinder as the circulating surface

          ∫ B. ds = μ₀ I

in this case the field is circular and ds is circular therefore the angle between them is zero and cos 0 = 1

          B 2π r =  μ₀ I

          r =  [tex]\frac{\mu_o I}{2\pi B}[/tex]

The field needed to demagnetize the card is B = 1000 gauss = 0.1 T

          r = [tex]\frac{4\pi 10^{-7} 5.0 }{2\pi \ 0.1}[/tex]

           r = 2 10⁻⁷  5.0/0.1

          r = 1  10⁻⁵ m

this distance is too small (r = 0.01 mm), therefore the cut can be at any distance

Question 2 of 15
When the source of a sound is moving, its speed increases.
A. True
B. False

Answers

False trust me gggvvbbbgffdfdxcbn
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