Answer; Ultrasonic waves (sounds having frequency greater than 20,000 Hz) are used in sonar because: ... Ultrasonic waves can penetrate water to long distances (because of their high frequency and very short wavelength), but ordinary sound waves or infrasonic waves cannot penetrate water to such long distances.
Answer:
Ultrasonic waves (sounds having frequency greater than 20,000 Hz) are used in sonar because: ... Ultrasonic waves can penetrate water to long distances (because of their high frequency and very short wavelength), but ordinary sound waves or infrasonic waves cannot penetrate water to such long distances
Explanation:
star a is composed of 60% hydrogen and star b has 54% hydrogen. which star is older and why
Answer: hello I think I'm in your class..
Explanation:
Mr. juhl is my teacher and he pit this on a test.
I'm Lennox
What will be acceleration due to gravity of a feather and coin if
they are dropped in vacuum?
Explanation:
Hey there!
We know that the objects in vacuum falls equally on the surface or bottom. As there is no air resistance in vacuum, the objects has equal stabdard acceleration. (i.e g = 9.8m/s^2)
So, the acceleration due to gravity is 9.8m/s^2.
Hope it helps....
Branden ran at 6 m/s for a time of 300s. How much distance did he cover during his run?
Answer:
The covered distance was 1800 [m]
Explanation:
In order to solve this problem we must use the following formula of kinematics. It is important to make it clear that Branden's speed never changes during that time, or therefore the speed is constant.
[tex]x = x_{o}+v*t\\[/tex]
where:
x = distance [m]
Xo = initial position = 0
v = velocity = 6 [m/s]
t = 300 [s]
Now replacing we have:
x = 0 + (6*300)
x = 1800 [m]
An elevator ascends at a constant speed of 4 m/s. How much time is required for the elevator in order to travel 200m upwards?
Answer:
Explanation:
Hope this helps, cheers
i really need help please just answer at least one
Answer:
9) a = 25 [m/s^2], t = 4 [s]
10) a = 0.0875 [m/s^2], t = 34.3 [s]
11) t = 32 [s]
Explanation:
To solve this problem we must use kinematics equations. In this way we have:
9)
a)
[tex]v_{f}^{2} = v_{i}^{2}-(2*a*x)\\[/tex]
where:
Vf = final velocity = 0
Vi = initial velocity = 100 [m/s]
a = acceleration [m/s^2]
x = distance = 200 [m]
Note: the final speed is zero, as the car stops completely when it stops. The negative sign of the equation means that the car loses speed or slows down as it stops.
0 = (100)^2 - (2*a*200)
a = 25 [m/s^2]
b)
Now using the following equation:
[tex]v_{f} =v_{i} - (a*t)[/tex]
0 = 100 - (25*t)
t = 4 [s]
10)
a)
To solve this problem we must use kinematics equations. In this way we have:
[tex]v_{f} ^{2} = v_{i} ^{2} + 2*a*(x-x_{o})[/tex]
Note: The positive sign of the equation means that the car increases his speed.
5^2 = 2^2 + 2*a*(125 - 5)
25 - 4 = 2*a* (120)
a = 0.0875 [m/s^2]
b)
Now using the following equation:
[tex]v_{f}= v_{i}+a*t\\[/tex]
5 = 2 + 0.0875*t
3 = 0.0875*t
t = 34.3 [s]
11)
To solve this problem we must use kinematics equations. In this way we have:
[tex]v_{f} ^{2} = v_{i} ^{2} + 2*a*(x-x_{o})[/tex]
10^2 = 2^2 + 2*a*(200 - 10)
100 - 4 = 2*a* (190)
a = 0.25 [m/s^2]
Now using the following equation:
[tex]v_{f}= v_{i}+a*t\\[/tex]
10 = 2 + 0.25*t
8 = 0.25*t
t = 32 [s]
Eclipses occur because the Moon?
A
does not create its own light and only reflects light from the Sun.
o
does not create its own light and only reflects the light from Earth.
o
с
creates its own light, which is blocked by the Sun during an eclipse.
creates its own light, which is blocked by Earth during an eclipse.
Answer:
с
creates its own light, which is blocked by the Sun during an eclipse.
Explanation:
might not be right but its what i remember
witch is the property of matter in witch a substance can transfer heat or electricity
Answer:
B. Conductivity.
Explanation:
Conductivity is the quantity of heat passing per second through a slab of unit cross-sectional area when the temperature gradient between the two faces is unity when put in heat.
write about any five form of energy with example
Answer:
The different types of energy include thermal energy, radiant energy, chemical energy, nuclear energy, electrical energy, motion energy, sound energy, elastic energy and gravitational energy.
Answer:
Chemical energy
Explanation:
Ex. gasoline, chemical batteries, and wood
Do) 13. Which image BEST represents our galaxy?
The best image of galaxy is second option.
What is galaxy?Galaxies are vast systems of gravity-bound gas, dust, dark matter, and anything from a million to a trillion stars. Supermassive black holes are expected to be present at the centers of almost all big galaxies. The sun is merely one of 100 to 400 billion rotating stars in our own galaxy, the Milky Way.
There are more galaxies visible as we gaze farther into space. According to a 2016 study, there are two trillion, or two million million, galaxies in the observable universe. While some of those far-off systems resemble our own Milky Way galaxy, others are very dissimilar,
There are three general types of galaxies elliptical, spiral, and irregular.
So the best shape is second option elliptical with boundary.
To learn more about galaxy refer to the link:
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4. Why do chemists use relative masses of atoms compared to a reference isotope rather than the
actual masses of the atoms?
a. The actual mass of an electron is very large compared to the actual mass of a proton.
b. The actual masses of atoms are very small and difficult to work with.
c. The number of subatomic particles in atoms of different elements varies.
d. The actual masses of protons, electrons, and neutrons are not known.
Answer:
B
Explanation:
Answer:
answer is B
Explanation:
took the test
How do muscles help the body move?
A. The muscle contracts causing the tendon to pull the bone.
B. The muscle pushes against a joint.
C. One muscle pulls on another muscle.
D. The ligament pulls on the muscle attached to the bone
Answer:
Hello
A. The muscle contracts causing the tendon to pull the bone.
Answer: A
Explanation: The muscle contracts causing the tendon to pull the bone.
A neutral atom of alluminum has 13 protons and how many electrons
Answer: also 13
Explanation: because there have to be an equal number of protons,neutrons,and electrons to make the atom stable.
how can magnetic potential energy be transferred to kinetic energy
Answer:
A magnetic force can convert kinetic energy stored in a magnetic field to potential energy. Kinetic energy can convert potential energy stored in a gravitational field. A magnetic energy can convert potential energy stored in a gravitational field to kinetic energy.
Anna is conducting an experiment to determine how weather affects cell phone reception. She is trying to decide the best way to conduct her experiment in order to collect meaningful data.
Which of the following experiments would help Anna collect the best data?
A.
Test different cell phones in different locations on days with rainy weather.
B.
Test different cell phones in different locations on days with clear weather.
C.
Test a cell phone's reception in the exact same location under various atmospheric conditions.
D.
Test a cell phone's reception in one location with clear weather and in another location with rainy weather.
A textbook that weighs 2 Newtons is lifted 4 meters. How much work is done on the book?
Answer:
The answer is 8 JExplanation:
The work done by an object can be found by using the formula
workdone = weight × distanceFrom the question
weight = 2 N
distance = 4 m
We have
workdone = 2 × 4
We have the final answer as
8 JHope this helps you
A dog is 60m away while moving at constant velocity of 10m/s towards you. Where is the dog after 4 seconds?
How many valence electrons does chlorine have?
Podbijest has a net force of 49 Nading on it and it is accelerating at a rate of 8 mil. What is its med
5 kg
8 kg
40 kg
48 kg
Answer:
6.125kg
Explanation:
Given parameters:
Force = 49N
acceleration = 8m/s²
Unknown:
Mass of the object = ?
Solution:
From newton's second law;
Force = mass x acceleratioin
49 = mass x 8
mass = [tex]\frac{49}{8}[/tex] = 6.125kg
what is measurement ?
Answer:
Measurement is the assignment of a number to a characteristic of an object or event
Explanation:
Answer:
Measurement is the assignment of a number to a characteristic of an object or event, which can be compared with other objects or event
Bob is pushing a heavy couch to another part of the living room. Bob is pushing with a force of 10 N to the right while the couch is pushing against Bob with a force of 8 N. What is the total net force due to Bob's pushing?
A. 18N to the right
B. 2N to the right
C. 18N to the left
D. 2N to the left
7. Your teacher has mixed salt, pepper, and water. Describe a procedure that you could use to separate this mixture. Be sure to list all of the materials you would need, your set up, and your expected results.
Answer:
hope this could help you
draw a diagram of a seismometer showing how the movement of earth is lated into a siesmogram
idk but it seems hard.
The length of the life cycle of a star depends on _.
distance from Earth
the nebula’s brightness
mass and the amount of matter
helium and the amount of matter
Answer:
c.mass and the amount of matter
A thin film of oil with a thickness of 90 nm rests on top of a pool of water. When white light incident on the film is reflected, what color (wavelength of the first order) is seen? The refractive index of the oil is noil =1.45 and of water is nwater=1.33
Answer:
m=0, λ₀ = 522 10⁻⁹ m
Explanation:
In this case we can see that the first boy M The reflected light suffers an interference phenomenon, let's analyze what happens on each surface
* When light passes from a medium with a lower refractive index to a medium with a higher refractive index, it undergoes a phase change of pi rad (180º).
This occurs when passing from air to oil, but not at the oil-water interface.
* within the material the wavelength changes by the refractive index
λₙ = λ₀ / n
therefore introducing this into the constructive interference equation and assuming almost perpendicular incidence remains
2 t = (m + ½) λₙ
2t = (m + ½) λ₀ / n
λ₀ = 2t n / (m + ½)
light in the first order (m = 1)
λ₀ = 2 90 10⁻⁹ 1.45 / (1+ ½)
λ₀ = 174 10⁻⁹ m
the light for zero order (m = 0)
λ₀ = 2 90 10⁻⁹ 1.45 / (0+ ½)
λ₀ = 522 10⁻⁹ m
this radiation in the visible range in the green region
A 7kg of ball experiences a net force of 5N, what will be its acceleration.
If the distance from the Earth’s center to the Moon’s center were suddenly doubled, what would occur to the gravitational force between them?
(A) Gravitational force would decrease by a factor of 4.
(B) Gravitational force would increase by a factor of 4.
(C) Gravitational force would decrease by a factor of 2.
(D) Gravitational force would increase by a factor of 2.
Answer:
C)Gravitational force would decrease by a factor of 2.
Explanation:
Hope this helps :)
When you sit in a chair, your body exerts a downward force on the chair. What
is the reaction force?
A. The floor pushes up on the chair.
B. The chair pushes down on the floor.
C. Earth's gravity pulls up on the chain
D. The chair pushes up on your body.
Answer:
ITS D !!!
Explanation:
IN ME WE TRUST
When you sit on the chair, your body will exert a downward force and in reaction, the chair pushes up on your body. Hence, option D is correct.
What is a Reaction Force?A building experiences a reaction force when it rests against another object. Calculating the reaction forces at the supports as a result of the forces operating on the beam is a necessary step in the analysis of a beam structure. The reaction forces can be calculated using a free body diagram of the entire beam.
Corrosion can be caused by reaction forces. For instance, due to the system's increased stiffness, reaction forces increase when bearing clearances are reduced from 350 mm to 150 mm.
According to the question, when the body will exert a downward force that is mg due to gravity, the chair will make a normal reaction force which will be equal to the force applied by the body on the chair.
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HELP GIVING BRAINLIEST
Answer:
16: x4
17 x2
18; 4.5 for q1 and 4.5 for q2
Explanation:
What is weight? and what is mass
When a closed can is heated, the pressure inside it increases. This happens because
Answer:
the heat is growing the particles bigger
Explanation: