Answer:Reflection
Explanation:
"Reflection" is the wave interaction responsible for echoes. The correct answer is C.
Reflection is the wave interaction responsible for echoes. When a wave encounters a surface that cannot transmit or absorb it, the wave is reflected back in the opposite direction. The reflected wave can then be detected by a receiver, creating an echo.
Echoes are commonly heard in environments where sound waves encounter hard surfaces such as walls, mountains, or cliffs. The sound waves bounce off the surfaces and return to the listener's ear, creating a delayed repetition of the original sound. This effect is commonly used in sonar and radar systems, which use reflected sound waves to detect objects and determine their distance and location.
To learn about the amplitude of a wave click:
https://brainly.com/question/29775285
#SPJ7
A car of mass 1800000 g, going 150 km/h rear ends a truck, 5500 kg going 100000 m/h. What are their velocities after an elastic collision in one dimension?
Answer:
v = 2099.5 km/h, v' = -618.8 km/h
or
v =-1996.6 km/h, v' = 721.7 km/h
Explanation:
From the law of conservation of momentum,
Total momentum before collision = Total momentum after collision
For elastic,
mu+m'u' = mv+m'v'..................... Equation 1
Total kinetic energy before collision is equal to total kinetic energy after collision
mu²+m'u'² = mv²+m'v'²............. Equation 2
Where m and m' are the mass of the car and truck respectively, and u and u' are the initial velocity of the car and the truck respectively, v and v' are the final velocity of the car and the truck respectively.
Given: m = 1800000 g = 1800 kg, m' = 5500 kg, u = 150 km/h, u' = 100000 km/h
Substitute these values into equation 1 and 2
1800(150)+5500(100000) = 1800v+5500v'
1800v+5500v' = 375500................... Equation 3
1800(150²) +5500(100000²) = 1800v²+5500v'²...................... Equation 4
Solving equation 3 and 4 simultaneously,
v = 2099.5 km/h, v' = -618.8 km/h
or
v =-1996.6 km/h, v' = 721.7 km/h
A student is provided with a rubber cylinder and a patch of synthetic fur. The rubber cylinder and the patch are electrically neutral. The student rubs the cylinder back and forth along the fur. A short time later, after the cylinder and fur have been placed on insulating stands, the student determines that the fur has a net negative electric charge. Before the patch of fur attained its net negative charge, it was considered to be electrically neutral. Which of the following claims, with appropriate evidence, is correct about the distribution of charge in the patch of fur before the charging process?
a. It is an isolated system.
b. It is a closed system.
c. It is an open system.
d. The type of system cannot be determined unless information is known about the net force exerted on the system at any given time.
Answer:
Option b ( It is a closed system) is the appropriate answer.
Explanation:
The mass transfer isn't made on a platform. There seems to be no mass transfer, the mechanism can't be separated as power lines will interfere beyond the physical boundaries including its fur patch.The mechanism can't however be separated and, while the mass transfer is indeed not present, several field lines will communicate well outside the mechanism.The other options are not linked to the situation in question. Thus, the answer is correct.
It is 32 degrees F outside. What is this in Kelvin?
Answer:
273.15
Explanation:(32°F − 32) × 5/9 + 273.15 = 273.15K
What determines the precision of a measurement?
Answer:
Precision is determined by a statistical method called a standard deviation To determine if a value is precise find the average of your data, then subtract each measurement from it
What is the motion of an apple when it falls from a tree ? a)Constant b)accelerating c)decelerating d)zero
The motion of an apple when it falls from a tree is
b) Accelerating
The motion of apple is when it falls from a tree is the case of free fall.
During free fall , the initial velocity of the apple or any object is zero but it gains some velocity due to gravitatonal acceleration .
To measure the internal diameter of a beaker one would reliably use______.
Answer:
Vernier calipers is used to measure the internal diameter of a beaker
How least count determine the precision of a measurement?
Explanation:
The least count of the normal scale is 1mm whereas the least count of vernier calliper is 0.01 mm
It has been shown that the half-life for this radioactive isotope is 20 years. In the year 2000, an archaeology team unearths pottery and is using this isotope for radiometric dating to place the age of the pottery. It is shown that 95% of the nuclei have decayed. How much mass has decayed? How much mass is left?
I'd prefer to be shown a step-by-step on how to solve for these questions. I do better with seeing the step-by-step, and can retain the information better.
Answer:
(1/2)*n = .05 by the definition of half-life where n is the number of half-lives
n ln .5 = ln .05
n = ln .05 / ln .5 = 4.32 number of half-lives
So 4.32 * 20 = 86.4 years has passed
Actually, they only want the mass left. However, all that has changed is that
95% of the original radioactive atoms have changed to a different form of about the same amount of mass. The amount of mass remaining would be about the same. Also, one doesn't know the percentage of radioactive atoms
that formed the original mass.
What is Kirchoff law
Answer:
.
Kirchhoff's circuit laws are two equalities that deal with the current and potential difference (commonly known as voltage) in the lumped element model of electrical circuits. They were first described in 1845 by German physicist Gustav Kirchhoff.[1] This generalized the work of Georg Ohm and preceded the work of James Clerk Maxwell. Widely used in electrical engineering, they are also called Kirchhoff's rules or simply Kirchhoff's laws. These laws can be applied in time and frequency domains and form the basis for network analysis.
Both of Kirchhoff's laws can be understood as corollaries of Maxwell's equations in the low-frequency limit. They are accurate for DC circuits, and for AC circuits at frequencies where the wavelengths of electromagnetic radiation are very large compared to the circuits.
how long does GSR last ?
A) nearly forever, indefinitely
B) not long at all
C) one day
D) one month
Answer:
i think that the answer might be be C. one day. because it last about 4 to 6 hours
Question 10 of 10
Which of the following is an example of a surface wave?
Answer:
gravity wave
Explanation:
Which statement best describes how resources are distributed?
according to it's nature
Which of the following should you do to improve your fitness level and increase your assessment scores by the end of the semester?
OA Watch a lot of TV
B.
Perform cardiovascular exercise
OC. Eat a diet high in fat and sugar
OD
All of the above
It’s Not Lhysics It’s Pe btw
Two boys are at the top of a waterslide at Seven Peaks Water Park. One boy (boy A) slips off the top of the tower and falls unobstructed into the pool below. At the same moment the other boy (boy B) starts sliding down the slide and lands in the same pool. Ignoring air resistance and friction, which boy will splash into the water first and which will have the greater speed when he hits the water?
Answer: boy B, same
Explanation:
Given
One boy trips off the waterslide while the other starts sliding down
As there is no horizontal velocity, both boys have to travel the same vertical distance.
Their starting vertical velocity is zero and they need to travel the same vertical distance. Therefore, both boys splash water with the same velocity.
The time taken by boy B is more than boy A as boy B will travel some horizontal distance due to slide which will increase its time to reach the bottom.
When two trains, going in opposite directions, are passing on tracks that are laid out close together, the train cars can often be seen to be leaning in toward one another where they are in proximity. How might the air passing through the narrow gap separating the two trains contribute to the observed attraction between their cars?
In a laser cutting process of aluminum plates of 1mm thick, a through hole is to be drilled, followed by melting-dominated cutting. If the focused laser beam is 0.25 mm in diameter (assuming it is the same of the cut width w), (a) In order to drill a hole through the plate in 1 ms, determine the laser power required. (b) In the cutting, the laser power is adjusted to be 1,500W. Determine the cutting velocity V achievable.
Answer:
a) P = 118.4 W, b) t = 7.9 10⁻⁵ s
Explanation:
a) Let's analyze this interesting exercise a bit, we suppose that all the laser
energy is used to heat the aluminum, we should calculate the energy necessary to bring the solid aluminum to the melting temperature and add the energy to carry out the change of solid state to liquid,
let's use the calorimeter equation
Q₁ = m c_e ΔT
and the energy of change of these solid to liquid (fusion process)
Q₂ = m L
the energy required to create the hole is
Q_ {total} = Q₁ + Q₂
if there are no losses this is the laser energy
E = Q_ {total}
The aluminun data c_e =9000 J/kgC, L = 322 103 J/kg, ρ = 2.7 103 kg/m3 , T₂ = 660C, T₀= 25C
Let's find the mass of the hole, which we approximate by a cylinder of diameter d = 0.25 mm = 0.25 10⁻³ m and a thickness of e = 1 mm = 1 10⁻³ m
let's use the concept of density
ρ = m / V
the volume of a cylinder is
V = π r² e = π (d²/4) e
we substitute
m = [tex]\rho \pi \frac{d^2 e}{4}[/tex]
let's calculate
m = π/4 2.7 10³ (0.25 10⁻³)² 1 10⁻³
m = 1,325 10⁻⁷ kg
we calculate the energy
E = 1,325 10⁻⁷ 900 (660 - 25) + 1,325 10⁻⁷ 322 10³
E = 7.57 10⁻² + 4.27 10⁻²
E = 1.184 10⁻¹ J
Let's use the power ratio
P = E / t
P = 0.1184 /1 10⁻³
P = 118.4 W
b) In this part they indicate that the laser power is P = 1500 W, find the time to deposit the energy to melt the aluminum
P = E / t
t = E / P
t = 0.1184 / 1500
t = 7.9 10⁻⁵ s
Help me pleaseeeeeeee
Answer:
2. - B.
3. - True.
4. - B.
5. - D.
Explanation:
2. To find the speed in feet per minute, you need to divide the time by time and divide the feet by the time
2/2 = 1 minute
100/2 = 50 feet
3. 45 N - 20 N = 15 N
So the difference between the forces is 15 N
4. As just about everyone knows, when something falls, that is because of gravity. Gravity is the force that pulls everything.
5. Inertia is when an object stays unchanged. So if something stays in motion or does not stop, it has not changed
The volume of the vessel is reduced twice,and the number of molecules is reduced three times.How the pressure will change gas?
Answer:
P₁ = ⅔ P₀
Explanation:
For this exercise we can use the ideal gas equation
PV = n R T
let's write the equation for the initial point, where we will use the subscript o and the end with subscript 2
Suppose the temperature does not change in the process
P₀V₀ / n₀ = P₁V₁ / n₁
They tell us that
V₁ = V₀ / 2
n₁ = n₀ / 3
we substitute
[tex]P_o \frac{V_o}{n_o} = P_1 \frac{V_o}{2} \frac{3}{n_o}[/tex]
P₀ = [tex]\frac{3}{2}[/tex] P₁
P₁ = ⅔ P₀
Question is in the image
Answer:
thank you
Explanation:
Tsunamis are fast-moving waves often generated by underwater earthquakes. In the deep ocean their amplitude is barely noticable, but upon reaching shore, they can rise up to the astonishing height of a six-story building. One tsunami, generated off the Aleutian islands in Alaska, had a wavelength of 668 km and traveled a distance of 3180 km in 4.81 h. (a) What was the speed (in m/s) of the wave
Answer:
215.5 m/s
Explanation:
Given that:
the wavelength λ = 668 km
distance (d) = 3180 km
time t = 4.81 hr
[tex]a) speed (v) =\dfrac{distance}{time}[/tex]
[tex]speed (v) =\dfrac{3180}{4.1}[/tex]
[tex]speed (v) =775.61 \ km/h[/tex]
[tex]speed (v) =(\dfrac{775.61\times 1000 }{3600}) \ m/s[/tex]
[tex]speed(v) = 215.5 \ m/s[/tex]
The frequency is:
[tex]f = \dfrac{v}{\lambda}[/tex]
[tex]f = \dfrac{215.5 }{668 \times 1000}[/tex]
[tex]f = 3.226 \times 10^{-4} \ Hz[/tex]
c)
The period:
[tex]T = \dfrac{1}{f}[/tex]
[tex]T = \dfrac{1}{3.226 \times 10^{-4}}[/tex]
T = 3099.8 seconds
The place you get your hair cut has two nearly parallel mirrors 6.5 m apart. As you sit in the chair, your head is 2.0 m from the nearer mirror. Looking toward this mirror, you first see your face and then, farther away, the back of your head. (The mirrors need to be slightly nonparallel for you to be able to see the back of your head, but you can treat them as parallel in this problem). How far away does the back of your head appear to be?
Answer:
13 m
Explanation:
It is given that :
I got a haircut sitting at a place having two parallel mirrors at a distance = 6.5 m apart
My head is at a distance of 2 m from the nearer mirror.
Now the light from the back of my head must go to (6.5 - 2) = 4.5 m to the back mirror.
Then it must go to 6.5 m to the front mirror and 2 m from the front mirror to my eyes.
So in order to see the back of my head, it will be = 6.5 + 2 + 4.5 = 13 m away.
A solenoid that is 69.3 cm long has a cross-sectional area of 24.0 cm2. There are 1260 turns of wire carrying a current of 8.78 A. (a) Calculate the energy density of the magnetic field inside the solenoid. (b) Find the total energy in joules stored in the magnetic field there (neglect end effects).
Answer:
a) 34.17J/m^3
b) 0.0468 J
Explanation:
a) Calculate the energy density of the magnetic field inside the solenoid as follows:
[tex]u_{B} &=\frac{U}{A l} \\ &=\frac{L I^{2}}{2 A l} \quad\left(U=\frac{1}{2} L I^{2}\right) \\ &=\frac{\mu_{0} N^{2} A I^{2}}{2 A l^{2}} \quad\left(L=\frac{\mu_{0} N^{2} A}{l}\right) \\ &=\frac{\mu_{0} N^{2} I^{2}}{2 l^{2}}[/tex]
Substitute the corresponding values in the above equation.
[tex]u_{B} &=\frac{4 \pi\left(10^{-7}\right)(1260)^{2}(8.78)^{2}}{2(0.693)^{2}} \\
&=34.17 \mathrm{~J} / \mathrm{m}^{3}[/tex]
b) Calculate the total energy stored in the solenoid as follows:
[tex]U &=u_{B} A l \\ &=(34.17)\left(24 \times 10^{-4}\right)\left(69.3 \times 10^{-2}\right) \\ &=0.0468 \mathrm{~J}[/tex]
A glacier advanced down a mountain from an elevation of 2010 m to 1780 m in 5 years. What was the glaciers rate of change in a year and a month?
the answer must also be shown in a graph
Answer:
The solution of the given problem is provided in the following subsection.
Explanation:
According to the question,
The change in the height of the glacier will be:
= [tex]1780-2010[/tex]
= [tex]-230[/tex]
Change in time,
= 5 years
Now,
The rate of change will be:
= [tex]\frac{m}{years}[/tex] ∵ (1 year = 12 months)
= [tex]\frac{230}{5}[/tex]
= [tex]-46 \ m/years[/tex]
or,
The rate of change will be:
= [tex]\frac{m}{months}[/tex] ∵ (5 years in months = 5×12 months)
= [tex]\frac{-230}{5\times 12}[/tex]
= [tex]\frac{-230}{60}[/tex]
= [tex]=3.83 \ m/months[/tex]
Which statement describes a drawback of digital medical records over paper records?
a) Digital records may be more difficult to read than handwritten records.
b) Digital medical records might be impossible to access in a power outage.
c) Digital records would be less safe if there was a fire.
d) Digital records have no way to limit access to private information.
Answer:
b)
Explanation:
From the options provided, the only drawback of using digital medical records is that Digital medical records might be impossible to access in a power outage. This is because digital records are saved on a database either locally or remotely. Regardless of which, the records can only be accessed through an authorized computer system that is connected to the database. These are electronic systems that require power to function. Without power you would not be able to use the computer and therefore, would not have access to the medical records. Unlike, paper records which can be accessed regardless of whether there is power or not.
PLEASE PLEASE HELP!! Do ultraviolet light or microwaves have a higher frequency?
Answer:The different types of radiation are defined by the the amount of energy found in the photons. Radio waves have photons with low energies, microwave photons have a little more energy than radio waves, infrared photons have still more, then visible, ultraviolet, X-rays, and, the most energetic of all, gamma-rays.
Explanation:
A 4 kg particle moves at a constant speed of 2.5 m/s around acircle of radius 2 m. What is its angular momentum about the center of the circle? Answerin units of kg · m2/s. What is its moment of inertia about an axis through the center ofthe circle and perpendicular to the plane of the motion? Answer inunits of kg · m2. What is t
Explanation:
Given that,
Mass of the particle, m = 4 kg
Speed of the particle, v = 2.5 m/s
The radius of the circle, r = 2 m
We need to find the angular momentum about the center of the circle. The formula for the angular momentum is given by :
[tex]L=mvr[/tex]
Substitute all the values,
[tex]L=4\times 2.5\times 2\\\\L=20\ kg{\cdot}m^2s[/tex]
So, the angular momentum of the particle is 20 kg-m² s.
A block of wood and a block of aluminum have been sitting out for a while. How do their temperatures compare?
Answer:
Block of aluminum
Explanation:
The block of aluminum because of the conductivity, and is a metal, so it gets hotter faster
The temperature of wood and the aluminium will depend upon thier thermal coductivity.
What is thermsal conductivity?The thermal conductivity of any material is defined as the amount of heat from a material can flow in a unit area per unit degree centigrade for a unit distance.
The thermal conductivity of wood is around 0.90 to 0.197 w/mk and that of aluminium is around 88 to 251 w/mk.
We can see that the aluminium block will absorb much amount of heat as compared to the wood block. Because the thermal conductivity of aluminium is much higher then the wood.
Hence temperature of wood and the aluminium will depend upon thier thermal coductivity.
To know more about Thermal conductivity follow
https://brainly.com/question/11213835
What is the logical relationship between the following two categorical propositions? Some food is not edible. Some food is inedible.
A. contrapositive
B. Subalternation
C. Obverse
D. contrary
1 gram of radium is reduced by 3.1 mg in 5 years by alpha decay.
Calculate the half-life of radium.
Answer:
1 gm = 1000 mg
N = No e^-y t where y = lambda the decay constant
N / N0 = .9969
ln .9969 = - y t
-.00310 = - 5 y
y = .00310 / 5 = .000621
So the half-life = .693 / y
T^1/2 = .693 / .000621 = 1116 or about 1120 yrs
Hey does anyone know the answer?
Answer:
C
Explanation:
The law of conservation of energy determines that energy cannot be created or destroyed.