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3 years ago

The diagram below shows the different phase transitions that occur in matter.

Physics

2 answers:

Margaret [11]3 years ago

7 0

Answer:A

Explanation:matter normally occurs in three phases;solid, liquid and gases. They may change from one phase to another due to temperature difference.

The molecules that makes up solids are held together by bonds. When heat is added,the molecules begin to move as a result,the bonds break and it turns to liquid.this process is called melting. The reverse of melting is freezing.

Liquid are made up of molecules that moves more freely than solids. When heat is added to liquid,the molecules gain more energy and begins to move faster. This causes them to turn to gases.

This process is called evaporation. It occurs at different temperature for different substances.

The particles of gases move more faster and are separated by large distances. A gas can change back to a liquid through condensation.

Luden [163]3 years ago

6 0

Answer:

A. Molecules are speeding up as boiling occurs.

Explanation:

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What is the frequency of a wave that has a wavelength of 20 cm and a speed of 10 m/s

jarptica [38.1K]

You would probably have a low frequency due to how much the wavelength is spread out.

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3 years ago

Cars A and B are racing each other along the same straight road in the following manner: Car A has a head start and is a distanc

4vir4ik [10]

The question is incomplete. Here is the complete question.

Cars A nad B are racing each other along the same straight road in the following manner: Car A has a head start and is a distance $D_{A}$ beyond the starting line at t = 0. The starting line is at x = 0. Car A travels at a constant speed $v_{A}$ . Car B starts at the starting line but has a better engine than Car A and thus Car B travels at a constant speed $v_{B}$ , which is greater than $v_{A}$ .

Part A: How long after Car B started the race will Car B catch up with Car A? Express the time in terms of given quantities.

Part B: How far from Car B's starting line will the cars be when Car B passes Car A? Express your answer in terms of known quantities.

Answer: Part A: $t=\frac{D_{A}}{v_{B}-v_{A}}$

Part B: $x_{B}=\frac{v_{B}D_{A}}{v_{B}-v_{A}}$

Explanation: First, let's write an equation of motion for each car.

Both cars travels with constant speed. So, they are an uniform rectilinear motion and its position equation is of the form:

$x=x_{0}+vt$

where

$x_{0}$ is initial position

v is velocity

t is time

Car A started the race at a distance. So at t = 0, initial position is $D_{A}$ .

The equation will be:

$x_{A}=D_{A}+v_{A}t$

Car B started at the starting line. So, its equation is

$x_{B}=v_{B}t$

Part A: When they meet, both car are at "the same position":

$D_{A}+v_{A}t=v_{B}t$

$v_{B}t-v_{A}t=D_{A}$

$t(v_{B}-v_{A})=D_{A}$

$t=\frac{D_{A}}{v_{B}-v_{A}}$

Car B meet with Car A after $t=\frac{D_{A}}{v_{B}-v_{A}}$ units of time.

Part B: With the meeting time, we can determine the position they will be:

$x_{B}=v_{B}(\frac{D_{A}}{v_{B}-v_{A}} )$

$x_{B}=\frac{v_{B}D_{A}}{v_{B}-v_{A}}$

Since Car B started at the starting line, the distance Car B will be when it passes Car A is $x_{B}=\frac{v_{B}D_{A}}{v_{B}-v_{A}}$ units of distance.

5 0

3 years ago

A car sitting at a red light begins to accelerate at 2 m/s2 when the light turns green. It continues with this acceleration unti

jek_recluse [69]

Answer:

x_total = 600 m

Explanation:

This is an exercise and kinematics, let's find the time it takes to reach the velocity 20 m / s

v = v₀ + a t

as part of rest v₀ = 0

t = v / a

t = 20/2

t = 10 s

let's find the distance traveled in this time

x₁ = vo t + ½ a t2

x₁ = 0 + ½ 2 10²

x₁ = 100 m

The remaining time is

t₂ = 35 - t

t₂ = 35 - 10

t₂ = 25 s

as in this range it has a constant speed

v = x₂ / t₂

x₂ = v t₂

x₂ = 20 25

x₂ = 500 m

the total distance traveled is

x_total = x₁ + x₂

x_total = 100 + 500

x_total = 600 m

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3 years ago

A star is moving away from an observer. Toward which end of the spectrum does its visible light shift?.

scZoUnD [109]

Answer:

Redshift, or lower power

Explanation:

doppler effect

waves get stretched when you are moving away from something, and squished when you are moving towards it. Imagine you have a long, bent wire. if you stretch out the wire, the wavelength becomes longer. This also applies to sound.

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2 years ago

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pishuonlain [190]

<span>10 inches
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3 years ago

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