Khi tia tới hợp với pháp tuyến tại điểm một góc i = 30 độ thì tia phản xạ hợp với pháp tuyến tại điểm tới một góc
A. i' = 90 độ B. i' = 45 độ
C. i' = 30 độ D. i' = 60 độ

Answers

Answer 1

Answer:

h jo

yhufjffj

m

m

m

m

m

n

m

j.j

j

njbgjbhggh

kjbn


Related Questions

If the distance between the first and the ninth crests in a string is 320 cm on the way velocity is 8 m/s calculate the periodic time

Answers

Áp dụng công thức tính bước sóng nhé

An atom contains 15 electrons. How many protons are present in the atom?

Answers

Answer:

15 protons.

Explanation:

The atomic number is the number of electrons as well as the number of protons whereas, the atomic mass is the number of neutrons and number of protons.

Answer:

15 protons

Explanation:

because the atom's electrons is always the same number as the atom's protons

hope it helps

HAPPY HALLOWEEN

Have a nice day

Examples of pressure in physics

Answers

Answer:

kettle boiling is an example of pressure in physics

Describe one unique/different food from your country

Answers

My country is Pakistan.
In pakistan, there’s a very popular dish called biryani which consists of rice and meat. often times it’s very spicy.

calculate the work done by a girl of mass 40 kg when she climbs a stair case of 20 steps each of height 10 cm and acceleration is 10Nkg^-1​

Answers

Answer:

i think its a 800x² hope you like it

Answer:

8964

Explanation:

465

If a truck starts from rest and it has acceleration of 4 m/s for 5 second calculate its final velocity. What will be the distance travelled by the truck during the time interval? ​

Answers

Answer:

20m/s final velocity, 60meters is the distance

Explanation:

since it accelerates 4m/s we can assume every second it goes up by 4 so we do 5×4=20...

while for the distance we have to think about the fact that every second the speed changes (precisely every second adding 4m/s) so in the first second its going to travel 4 meters in the second 8m in the third 12m in the fourth 16m and in the fifth 20m... so we just calculate them for addition and get 60 meters

Newtons and Coulombs Laws QC
(Look to the bottom for answers 100% correct)

1. Which law gives the force between two objects that is related to their mass and distance?
A. Newton's second law of motion
B. Kepler's law
C. Newton's law of gravitation
D. Coulomb's law

2. What is the property that allows a positive proton and a negative electron to feel an attraction between each other?
A. Mass
B. Weight
C. Charge
D. Spin

3. In which case would there be an electrostatic force between two objects?
A. Two positively charged objects
B. A negatively charged object and a neutral object
C. A positively charged object and a neutral charged objects
D. Two neutral objects

4. Which statement is correct about electrostatic force?
A. It can have a positive or negative value
B. It is only observed between two electrons
C. It depends on the mass if the charges
D. It is independent of the distance between charges

5. In the simulation, two charges are both set to +4 uC. Then one of the charges is charged to -4 uC. Which statement describes the situation?
A. The electrostatic force is originally repulsive and stays repulsive.
B. The electrostatic force is originally attractive and stays attractive.
C. The electrostatic force changes from attractive to repulsive.
D. The electrostatic force changes from repulsive to attractive.

Answers:
1. C
2. C
3. A
4. A
5. D

BE SURE TO CHECK THE ORDER OF YOUR ANSWER CHOICES BECAUSE THEY CAN CHANGE.
100% is guaranteed

Answers

1c 2c 3a 4a 5d

Explanation:

I just know.

ur welcome.

eeee

The first one is wrong

Answers

Answer: goin at a constant rate

Explanation: goes through 0,0

A tennis ball is tossed upward with a speed of 3.0 m/s. We can ignore air resistance.
What is the velocity of the ball 0.40 s after the toss?

Answers

Answer: Hello, The velocity of the ball is 0.92 m/s in the downward direction (-0.92 m/s).

Explanation: The equation for the velocity of an object thrown upward is the following:

v = v0 + g · t

Where:

v = velocity of the ball.

v0 = initial velocity.

g = acceleration due to gravity (-9.8 m/s² considering the upward direction as positive).

t = time.

To find the velocity of the ball at t = 0.40 s, we have to replace "t" by 0.40 s in the equation:

v = v0 + g · t

v = 3.0 m/s - 9.8 m/s² · 0.40 s

v = -0.92 m/s

The velocity of the ball is 0.92 m/s in the downward direction (-0.92 m/s).

Hope That Helps

Writ the correct answer 'French word which means Rebirth, revival or rediscovery.'( MUSIC)

Answers

• Rebirth: réincarnation or renaissance
• Revival: reprise
• Rediscovery: redécouverte

Sammy feels an ocean breeze as he plays volleyball at the beach. Why do ocean winds or sea breezes blow toward shore during the day? Question 2 options: Air over the beach heats up, rises and is replaced by ocean air. Earth's rotation causes air to blow toward land. he energy of the ocean storms push air toward shore. Ocean air is less dense, so it rises to replace air over the land.

Answers

The heat coming from the sun warms the land more quickly than the sea. As a result of these, the air near the land warm up and rises and the cooler air from the sea moves in to replace the risen air. The correct answer is option A

There will be heat transfer from a region of higher temperature to the region of lower temperature. But in the case of land and sea breeze, the transfer of heat are the result of convectional current in nature. Because the land is a better absorber of heat and also has a lower specific heat capacity compare to sea, during the day, the heat coming from the sun warms the land more quickly than the sea. As a result of these, the air near the land warm up and rises.

The cooler air from the sea moves in to replace the risen air.

Why do ocean winds or sea breezes blow toward shore during the day ? It is because air over the beach heats up, rises and is replaced by ocean air.

Therefore, option A is correct

Learn more here : https://brainly.com/question/1114842

I NEED THE RIGHT ANSWER ASAP IT NEEDS TO BE 100% ACCURATE NO LINKS !!!
Which statement about vectors is true?
1:Vectors are quantities described by both velocity and acceleration.
2: Vectors are quantities described by both magnitude and direction.
3: Vectors are quantities described by both speed and movement.
4: Vectors are quantities described by both force and gravity.

Answers

Answer:

I will answer before the bot in comments

why it is important to have a regular
supervision of the weight and measurement and in the market ​

Answers

Supervision of weights and measures promotes accurate measurements of goods and services to ensure that everybody gets a fair trade in the marketplace. Not so coincidentally it also is a deterrent to ensure that traders are being honest in their trade practises. Then look at the construction industry. Without constant adherence to accuracy any building/bridge or other construction would soon lose its integrity.

bus slows down uniformly from 21 m/s to 0 m/s in 21 s. How far does it travel before stopping?

Answers

Answer:

1 hour = 3,600 seconds

1 km = 1,000 meters

75 km/hour = (75,000/3,600) m/s =  20-5/6 m/s

The average speed of the bus while it slows down is

                                   (1/2)(20-5/6 + 0) = 10-5/12 m/s .

Traveling at an average of 10-5/12 m/s for 21 seconds,

the bus covers

                         (10-5/12) x (21) =  218.75 meters .

do not own the answer

answer by (AL2006 from brainly)

Which is evidence for the existence of dark energy?
Black holes that are expanding at a constant rate.

Pulsars that seem to be moving closer at an accelerating rate.

Supernovae that are moving away at an accelerating rate.

Galaxies that are rotating at a constant rate.

Answers

Answer: it’s Supernovae that are moving away at an accelerating rate.

The evidence for the existence of dark energy is that Supernovae that are moving away at an accelerating rate.

is evidence for the existence of dark energy.

The first known evidence for dark energy came through from close watch of supernovae in 1998.

Much more evidence took taken earlier the year from a survey of 250,000 galaxies.

Dark matter are often known to be matter that we cannot see but one which can exerts a gravitational influence on stars and galaxies.

Learn more from

https://brainly.com/question/24930439

1.) Is it possible for an object to move in a direction that is different from the direction of the net force acting on the object? (an example would be much appreciated). ​

Answers

Answer:

No,unless the force is balanced and the object doesn't move .

how much heat must you remove from the 2.00 kg of 41.3 C tea to lower its temperature to 0.0 C?

Answers

Mass=m=2kgInitial temperature=41.3°CSpecific heat capacity=4184J/kgKFinal temperature=0°C

Using thermodynamics

[tex]\\ \sf\longmapsto Q=mc\Delta T[/tex]

[tex]\\ \sf\longmapsto Q=2(4184)(0-41.3)[/tex]

[tex]\\ \sf\longmapsto Q=8368(-41.3)[/tex]

[tex]\\ \sf\longmapsto Q=345598.4J[/tex]

leftover planetesimals that formed inside the frost line are known as

Answers

These are known as dwarf planets.

In this graph (mass vs volume), what does the slope represent? I will mark brainliest​

Answers

Answer:

Slope y2-y1/x2-x1

m=mass/volume

slope represents density(g/ml)

Explanation:

PLS MARK BRAINLIEST

Slope = Mass/ Volume = Density. The given slope represents Density.

Thus, Density is the mass of a material substance per unit volume. d = M/V, where d is density, M is mass, and V is volume, is the formula for density.

Grams per cubic centimeter are a typical unit of measurement for density.  For instance, air weighs 1.2 pounds per cubic metre. In textbooks and manuals, the densities of typical solids, liquids, and gases are stated.

The volume of a body is equal to the mass multiplied by the density (M = Vd), while the volume is equal to the mass divided by the density (V = M/d). Density provides a straightforward way to determine a body's mass from its volume, or vice versa.

Thus, Slope = Mass/ Volume = Density. The given slope represents Density.

Learn more about Density, refer to the link:

https://brainly.com/question/29775886

#SPJ6

10 points and BRAINLIEST? Could someone please provide 10 key facts about electricity? For the most reasonable answer, I'll follow you and rate your answer Excellent and give Brainliest!!!​

Answers

Answer:

Broadcasting empty threats is unwise

Explanation:

Roosevelt states that a man who boasts without backing himself up puts his position in jeopardy

the energy per unit volume in an electromagnetic wave is

Answers

Answer: sum of the electric field energy density and magnetic field energy density.

Explanation:

The total energy stored in an electromagnetic wave is equal to the sum of energy stored in the electric and magnetic fields. In that case, the energy stored per unit volume, or energy density of the electromagnetic wave, is the sum of the electric field energy density and magnetic field energy density.

A car starts from rest and retains the acceleration of 4m/s² in 20 second. calculate its final velocity.
step by step

Answers

Answer:

80m/s

Explanation:

[tex](acceleration)= \frac{(change \: in \: velocity)}{(change \: in \: time)}[/tex]

4 = v/20

V = 4 * 20

V = 80( final velocity)

no matter where you are on earth, stars appear to rotate about a point called the

Answers

Answer:

The Celestial Sphere

Explanation:

No matter where you are on Earth, stars appear to rotate about a point called the celestial pole.

Here's how it works:

Rotation of Earth: The Earth rotates on its axis from west to east. This rotation takes approximately 24 hours to complete one full rotation.

Celestial Poles: The celestial poles are imaginary points in the sky directly above the Earth's geographic poles. The North Celestial Pole is located directly above the Earth's North Pole, and the South Celestial Pole is located directly above the Earth's South Pole.

Apparent Motion: As the Earth rotates, the stars that are closer to the celestial poles appear to move in small circles around these poles. The stars that are farther away from the poles will have larger apparent circles.

Constellations and Circumpolar Stars: The constellations located near the celestial poles are known as circumpolar constellations. This means that they never fully set below the horizon from a specific location on Earth.

Equator and Horizon: The stars that are situated near the celestial equator (an imaginary line that's an extension of Earth's equator into the sky) will rise in the east, arc across the sky, and set in the west, much like the Sun does.

To know more about celestial pole:

https://brainly.com/question/30418300

#SPJ3

How do a proton and an electron compare?
A. The proton is farther from the nucleus.
B. They have opposite charges.
C. They are both found in the nucleus.
D. The electron has greater mass.

Answers

Answer:

b

Explanation:

proton and electron are exactly the same size but opposite

I need help with some physics stuff​ HELP

Answers

Answer:

You just double the number of boxes it goes higher. Then triple the number for the second question. But don't change the time.

you are given two circuits with two batteries of emf e and internal resistance r1 each. circuit a has the batteries connected in series with a resistor of resistance r2, and circuit b has the batteries connected in parallel to an equivalent resistor.

Answers

Answer:

In which direction does the current in circuit A flow?

counterclockwise

What is the power dissipated by the resistor of resistance R2 for circuit A, given that E=10 V, R1=300ohms, and R2=5000ohms? Calculate the power to two significant figures.0.064WFor what ratio of R1 and R2 would power dissipated by the resistor of resistance R2 be the same for circuit A and circuit B?R1/R2 = 1 Under which of the following conditions would power dissipated by the resistance R2 in circuit A be bigger than that of circuit B? Some answer choices overlap; choose the most restrictive answer.R2>R1

Explanation:

The current flowing through the circuit A is [tex]I = \frac{e}{r_1 + r_2}[/tex].

"Your question is not complete, it seems to be missing the following information",

find the the current flowing through the resistors in circuit A;

The given parameters;

emf of each battery = einternal resistance of circuit A = r₁resistance of circuit = r

The equivalent resistance of the circuit A in series is calculated as follows;

[tex]R_e = r_1 + r_2[/tex]

The emf of the battery connected to circuit A

emf = e

The current flowing through the circuit A is calculated as follows;

[tex]V= IR\\\\I = \frac{V}{R} \\\\I = \frac{e}{R_e} \\\\I = \frac{e}{r_1 + r_2}[/tex]

Thus, the current flowing through the circuit A is [tex]I = \frac{e}{r_1 + r_2}[/tex].

Learn more here:https://brainly.com/question/23008996

What do you call a molecule composed of two atoms of the same element?

Answers

Answer:

I believe it's called a diatomic atom

Evelyn learns that a sound wave can be recorded electronically as an analog signal or as a digital signal. She investigates these two signal types. She records her voice using a tape recorder, which uses an analog signal to produce sound when played back. She also records her voice using a computer, which uses a digital signal to produce sound when played back. Evelyn replays each recording 100 times.

a. Describe a difference that Evelyn would most likely hear between the two recordings after being replayed 100 times.

b. Explain why the two recordings would sound different after being replayed 100 times.

Answers

a)The analog signal's pitch and frequency change each time. It is continuous in the digital signal.

What is the digital signal?

A digital signal is one in which data is represented as a series of discrete numbers.

To reduce the influence of noise in communication, a digital signal is utilized. When compared to analog signals, digital signals convey more information per unit of time.

a)Evelyn would most likely notice a difference between the two recordings after hearing them 100 times is that the analog signal's pitch and frequency change each time. It is continuous in the digital signal.

b)After 100 replays, the two recordings would sound different since the digital signal has a greater quality throughout long-distance transmission.

When digital signals are transferred, the amount of bandwidth used is lowered.

Hence, the digital signal has a greater quality throughout long-distance transmission causing two recordings would sound different.

To learn more about digital signals refer to:

https://brainly.com/question/14825566

#SPJ1

identify a woman in sports and give a brief bio on her life and her contribution to the sporting discipline that she is notably involved in.

Answers

Answer:

Explanation:

These ground breaking women have achieved something no woman has achieved before. 1938: Babe Zaharias, the first female to play on the PGA Tour in the Los Angeles Open. She shot 81-84 and missed the cut.

The density of water is

Answers

Answer:

997 kg/m³

Explanation:

Answer:

997 kg/m³

Explanation:

Other Questions
what clues on a cbc would make a doctor suspect leukemia? Write your answer as a decimal-8.1 / 0.5 HELPPP!!! SOMEONE PLEEASEEE!!! :(URGENT!!!! Question 1 of 10This graph shows how the potential energy of a reaction system changesover time. Which statement is true for this system?BPotential energyReaction progressO A. The potential energy of the reactants is greater than the potentialenergy of the productsOB. The height of the curve at point A represents the activation energyO C. The height of the curve at point B represents the activation energy.O D. The potential energy of the products is greater than the potentialenergy of the reactants. Paano magsisilbing gabaysa pagpapasiya at pagkilos ang konsensiyang nahubog sa likas na batas moral? In the late 1800s, Western nations generally believed the peoples of Africa and Asiawere good Christians.* were less civilized.should learn English.should be industrialized. Evaluate the expression.-41-5(713)19]2(-1)What is the value of the expression? Do you work or are you a student? Is that a popular subject in your country? What are the most popular subjects in China? Why did you choose that university? What are your favorite classes/ courses/ subjects at university? A shirt that regularly sells for $20 is marked down by 30%. What is the new price ofthe shirt? 5What is the additive inverse of2 The movement of the progress bar may be uneven becouse questions can be worth more or less including zero) depending on your answerWhat is 35% of 28.6?0.10011.00110.010 100.1SubmitHoldPassDony know answerSkip for now What are some of the organelles in a plant cell? In this is in science A small school has 78 students. If 24 students are boys what is the ratio of girls to boys Which of the following describes point d? I need help on this one too Here is a list of numbers:15, 6, 13, 5, -14, 9, 8, 10, 15State the median. French comprhensionVista learning Answer choices are Un carUne carteLa vie dun collgien Une dlgue de classe Une matire Express the ratio below in its simplist form 9:9:3 1/2x - 5+ 2/3 x= 7/6x+4 help me please and thank you