Please help me
Think about a time when you walked down an empty hallway
and heard the echo of your footsteps. Write what you think
caused the echo.
Answer:
Explanation:
There are a few conditions as mentioned: "you walked down an empty hallway and heard the echo of your footsteps." So first thing is as you walk, your shoes touch the floor and make noises. Those are sounds of your footsteps. You are in a hallway so the sounds are trapped within the hallway. It is empty so there is nothing like people who would block and absorb the sounds. With sounds bouncing around walls and floor of the hallway, they bounce back to the source: you. That is when you hear the echo of your footsteps.
The particles that make up matter are ______, ions or molecules.
Answer:
Atoms.
Explanation:
Atoms are purely one bit of an element. Ions are positive or negative atoms. Molecules are not pure, they have other stuff with it.
Infrared light and visible light are both waves on the electromagnetic spectrum. Identify two
other similarities between infrared and visible light.
Answer:
Both travel in straight line
A block of mass 3. 0 kg is hung from a spring, causing it to stretch 12 cm at equilibrium, as shown above. The 3. 0 kg block is then replaced by a 4. 0 kg block, and the new block is released from the position shown above, at which the spring is unstretched. How far will the 4. 0 kg block fall before its direction is reversed?.
Answer: 32 cm
Explanation:
Students in science are studying solutions and the dissolving rate of solids. One group was given some instant lemonade mix to dissolve. They used a packet of lemonade crystals and a packet of lemonade powder. The students dissolved the same amount of each solid into 100 ml of water. They varied the water temperature. List ALL the possible conclusions based the data the students collected?
Answer:
a-d
Explanation:
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If a train going 60 m/s hits the brakes, and it takes the train 85 seconds to stop, what is
the train's acceleration?
Question :-
If a Train going with 60 m/s Speed hits the Brakes, and takes 85 sec to stop. What is the Acceleration of the Train ?Answer :-
Acceleration of Train is 0.70 m/s² .Explanation :-
As per the provided information in the given question, we have been given that the Speed of the Train is 60 m/s . Time taken to stop the Train is 85 sec . And, we have been asked to calculate the Acceleration of the Train .
For calculating the Acceleration , we will use the Formula :-
[tex] \bigstar \: \: \: \boxed { \sf{ \: Acceleration \: = \: \dfrac{v \: - \: u}{t} \: }} \\ [/tex]
Where ,
V denotes to Final Velocity .U denotes to Initial Velocity .T denotes to Time Taken .Therefore , by Substituting the given values in the above Formula :-
[tex] \dag \: \: \: \: \sf{Acceleration \: = \: \dfrac{Final \: Velocity \: - \: Initial \: Velocity}{Time} } \\ [/tex]
[tex] \longmapsto \: \: \: \sf{Acceleration \: = \: \dfrac{0 \: - \: 60}{85} } \\ [/tex]
[tex] \longmapsto \: \: \: \sf{Acceleration \: = \: \dfrac{60}{85} } \\ [/tex]
[tex] \longmapsto \: \: \: \textbf {\textsf {Acceleration \: = \: 0.70 }} [/tex]
Hence :-
Acceleration = 0.70 m/s² .[tex] \underline {\rule {210pt} {4pt}} [/tex]
Note :-
Kindly Scroll the Screen from Right to Left for Better View .Answer:
Question :-
If a Train going with 60 m/s Speed hits the Brakes, and takes 85 sec to stop. What is the Acceleration of the Train ?
Answer :-
Acceleration of Train is 0.70 m/s² .
Explanation :-
As per the provided information in the given question, we have been given that the Speed of the Train is 60 m/s . Time taken to stop the Train is 85 sec . And, we have been asked to calculate the Acceleration of the Train .
For calculating the Acceleration , we will use the Formula :-
\begin{gathered} \bigstar \: \: \: \boxed { \sf{ \: Acceleration \: = \: \dfrac{v \: - \: u}{t} \: }} \\ \end{gathered}
★
Acceleration=
t
v−u
Where ,
V denotes to Final Velocity .
U denotes to Initial Velocity .
T denotes to Time Taken .
Therefore , by Substituting the given values in the above Formula :-
\begin{gathered} \dag \: \: \: \: \sf{Acceleration \: = \: \dfrac{Final \: Velocity \: - \: Initial \: Velocity}{Time} } \\ \end{gathered}
†Acceleration=
Time
FinalVelocity−InitialVelocity
\begin{gathered} \longmapsto \: \: \: \sf{Acceleration \: = \: \dfrac{0 \: - \: 60}{85} } \\ \end{gathered}
⟼Acceleration=
85
0−60
\begin{gathered} \longmapsto \: \: \: \sf{Acceleration \: = \: \dfrac{60}{85} } \\ \end{gathered}
⟼Acceleration=
85
60
\longmapsto \: \: \: \textbf {\textsf {Acceleration \: = \: 0.70 }}⟼Acceleration = 0.70
Hence :-
Acceleration = 0.70 m/s² .
\underline {\rule {210pt} {4pt}}
Note :-
Kindly Scroll the Screen from Right to Left for Better View .
Control rods are used to slow down the reaction in the reactor core when the core becomes too hot. please select the best answer from the choices provided t f
In nuclear reactors, control rods are used because reactions that occur in a nuclear reactor are highly exothermic in nature.
What is a nuclear reactor?A nuclear reactor is an apparatus or structure in which radioactive material can be made to undergo a commanded, self-sufficient nuclear reaction with the resultant release of energy.
Therefore, when these control rods are infused in a nuclear reactor, than it absorbs the neutrons and helps to control the chain reaction. As a result, the rate of chain reaction gets in control.
Thus, we can conclude that the statement control rods are used to slow down the reaction in the reactor core when the core becomes too hot is a true statement.
Thus In nuclear reactors, control rods are used because reactions that occur in a nuclear reactor are highly exothermic in nature.
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Answer:
TRUE ( T )
Explanation:
Just took the test on edge
Two equivalent sinusoidal waves travel toward each other on a spring they interfere. What if the waves traveling toward each other aren't sinusoidal but a series of pulses as seen in the picture? What effect does this have on the spring?
Answer:
Superposition would take place
Explanation:
The waves would interfere with one another either in the form of Constructive Interference or Destructive Interference.
A softball and a basketball start from rest and roll down an incline. Which ball reaches the bottom first?
Answer:
both
Explanation:
gravity is the same for both
A ball rolls down an inclined plane, starting from rest. if the total time it takes to reach the end of the inclined plane is t, how much time has elapsed when it is halfway down the incline 0.5t
An inclined plane is a straightforward device with a sloping surface that is used to lift heavy objects. When friction is taken into account, the force needed to move an object up an incline is less than the weight being raised. The needed force is closer to the real weight the higher the slope or incline.
The inclined plane is the most basic of all simple machines because nothing needs to move for it to function. In order to save effort, you have to move objects farther when using an inclined plane. A variety of techniques can be used to create an inclined plane. It can be as simple as a log leaning against a tree in the woods or a piece of wood placed on the edge of a stair.
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HELP Due right now
A 1345-kg car moving east at 15.7m/s is struck by a 1923-kg car moving north. They stick together and move with a velocity of 14.5m / s at theta = 63.5 degrees Was the north-moving car exceeding the 20.1m / s speed limit?
Answer:
so here the initial momentum was all in the X direction. This is Equalling the mass. I'm someone multiplied by visa one initial Equalling 1345 kilograms multiplied by 15.7 meters per second. This is Equalling 2.11 times 10 to the fourth kilograms meters per second. Now the car stick together and we can say that the final momentum is Equalling. I'm someone plus himself to multiplied by the final velocity. This is gonna be equal to 1345 kilograms plus 1900 23 kilograms. This is multiplied by 14 0.5 meters per second. And we find that the final month Thomas Equalling 4.74 times 10 to the fourth kilograms meters per second. Now the y component of the final momentum, we can say that he's sub final. Why would be equaling two 4.74 times 10 to the fourth kilograms meters per second? This would be equally rather multiplied by sign of 63.5 degrees. This is Equalling 4.24 times 10 to the fourth kilograms meters per second. By law, of the conservation of momentum. We can say that the Y component of the final momentum equals the why component of the initial momentum. This is equaling EMS up to visa to initial and be some to initial is found to be equal to the final. The white component of final momentum divided by the second cars mass and so this would be 4.24 times tend to the fourth kilograms meters per second, divided by M sub 2 1923 kilograms and this is giving us 22.0 meters per second. And of course this is greater than 20 whether 20.1 meters per second. And so we can say that yes, this car is exceeding the speed limit.
Explanation:
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What is the tension of the string if the cylinder has an acceleration of
In physics, the tension on a suspended object said to be equal to the weight of the object plus or minus the mass of the object times the acceleration acting on it.
~ ISS
Find the kinetic energy k of the block at the moment labeled b. express your answer in terms of k and a.
The position of the object can be used to find the kinetic energy in terms of k and a.
What is kinetic energy?The term kinetic energy refers to the energy of an object that is in motion. The question is incomplete hence the syetem is not shown and the value of the kinetic energy can not be found in terms of k and a.
Hence, when the system is shown, we can look at the position of the system and use it to obtain the value of the kinetic energy in terms of k and a.
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Answer:
K = 3/8k(A)^2
Explanation: Potential Energy --> Conservation of Energy
Because block B is at A/2, U = 1/2k(A/2)^2 which equals U = 1/8k(A)^2.
Now that you have the equation for potential energy, you can find kinetic energy in terms of the spring constant (k) and amplitude (A).
K = 3/8 k A^2
Which statement describes the force diagram? the forces are balanced. the box will move to the right. the box will move to the left. the forces are unbalanced.
The answer will be A The forces are balanced. Force is an external agent applied on any object to displace it from its position. Force is a vector quantity, so with magnitude it also requires direction.
what is force?Force is an external agent applied on any object to displace it from its position. Force is a vector quantity, so with magnitude it also requires direction. Direction is necessary to examine the effect of the force and to find the equilibrium of the force.
The length of each arrow represents the magnitude of each force, while the direction of each arrow represents the direction of each force.
From the diagram, we see that the four arrows have all same length: this means that the four forces have same magnitude, therefore they are balanced in pair. In fact:
On the vertical direction, the normal reaction ([tex]F_N[/tex]) balances the weight of the box ([tex]F_g[/tex])
On the horizontal direction, the push ([tex]F_P[/tex]) balances the force of friction ([tex]F_f[/tex])
Hence the answer will be A. the forces are balanced.
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Answer:
A is your answer.
Explanation:
Good luck on your exam!
You research your favorite topic: earthquakes. You build a tall LEGO building, and you want to know which type of motion is most damaging to your building. You discover in your research that side-to-side motion is the worst. You will place the building on a piece of wood and shake it for durations of 30 seconds, 60 seconds, and 90 seconds. You will try an up-and-down motion and side-to-side motion.
Answer:
If the Lego building is shaken side to side, it will withstand up to 60 seconds because front to back will cause the top of the building to collapse.
What is the difference between a moon and a planet.
Answer:
A planet revolves around the Sun and a moon orbits a planet. Technically, the moon also orbits the Sun as it spins around its planet, but because it has its own sub-orbit of a planet scientists define it as a moon. All planets in our solar system, except for Mercury and Venus, have moons. Earth has one moon, Mars has two, Neptune has thirteen, Uranus has twenty-seven, Jupiter has sixty-six, and Saturn has sixty-two. Pluto, now classified as a dwarf planet, has five moons.
Different between :
Metalloids and alloys
Answer:
Alloys are just mixtures of metal and metalloids are metallic substances with properties of metal.
Answer:
metalloids are chemical elements that form substances that have properties of metals and non metals while alloys is a mixture of metals
A boy of mass 50kg runs a set of steps of total height of 10cm. Calculate the work done (g =10)
Answer:
Explanation:
w=F×S
F=mg
F =50×110
F=500N
S=0.1 m
W=500×0.1
W=50j
Your friend phred says ""i decided to make one of those online personality tests as a project in my psychology class. how hard can it be?"" part a: explain whether or not phred should use the following personality theories as a basis for his online personality test. • psychoanalytic perspective• humanistic theory• trait theory
Fredd must use the trait theory for the online personality tests because it is based on distinctive features.
What is the trait theory?The trait theory is a model that states people have certain basic personality traits which are distinctive features.
The trait theory is always based on the strength of these basic human trait characteristics.
The trait theory is based on three types of features capable of being used to describe personality, which include stability, consistency and individual differences.
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Imagine a situation : If people could not see colours, then how would traffic lights work ? Design a traffic system that does not rely on colors.
Answer:
position
Explanation:
Okay, so this already exists
Colorblind people use the position of the light
Red on top, yellow in middle, green on bottom
The question is in the attachment!!
Explanation:
|F|= B/2
B/2 = √(A²+B²+2ABcosθ) ------(1)
Since the resultant of A and B is perpendicular to Vector A
tan90°= BSinθ/(A+BCosθ)
(A+BCosθ)=0
Cosθ=-A/B ----(2)
Using equation (1)
B/2 = √(A²+B²+2ABcosθ)
B/2 = √(A²+B²+2AB×-A/B)
B/2=√(A²+B²-2A²)
B/2=√(B²-A²)
B²/4=B²-A²
A²=B²-B²/4
A²=3B²/4
A=√3B/2
Using equation (2)
Cosθ=-A/B
Cosθ=-[√3B/2]/B
Cosθ=-√3/2
θ= cos^-1 (-√3/2)
θ= 150°
A round tube weighs 30 lbs. If the tube is stood on end it pushes down on the floor with a pressure of
2 lbs/in?. How many square inches is the end of the tube?
Answer:
15in2
Explanation:
The diagram shows part of a radio antenna.The plastic tube protects the radio antenna from bad weather.Dust particles carried by the wind rub against the plastic tube.After some time, the dust particles cause the tube to become positively charged.State the property of plastic that allows it to become electrostatically charged.
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Two metal spheres having charges of 4. 0 × 10–6 coulomb and 2. 0 × 10–5 coulomb, respectively, are brought into contact and then separated. After separation, the charge on each sphere is
Answer:
12*10^(-6) or 1.2*10^(-5)
Explanation:
if both of spheres are in same size.
q after = (q1+q2)/2 = ( (4.0 + 20.0)*10^(-6) )/2 = 12*10^(-6) or 1.2*10^(-5)
A proton is moving south with a speed of 4500 m/s in a magnetic field of 5500 T directed into the page. Determine the magnitude and direction of the magnetic force on the charge.
a.3.96 x 10-12 N west
b.1.55 x 1026 west
c.1.55 x 1026 east
d.3.96 x 10-12 N east
Answer:
F = q V X B
V is south and B is into the page
The resultant vector is directed to the East
F = 1.6E-19 * 4.5E3 * 5.5E3 N = 3.96 N East
(Note q is negative for an electron producing a force in the opposite direction)
Seismic waves do not travel along the Earth’s surface. Please select the best answer from the choices provided T F.
Seismic waves do not travel along the Earth’s surface. The statement is false.
what are seismic waves?
The seismic waves can be defined as the waves full of energy that travel through the Earth's layer, these waves are the result of earthquake.
They can further be divided into two types body wave and surface waves. The body waves travel in the interior of the Earth and the surface waves travel at the surface of the Earth.
The seismic waves can have an amplitude of few centimeters in large earthquake. They travel slower as compared to the body waves.
Hence Seismic waves do not travel along the Earth’s surface. The statement is false.
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Answer:
False
Explanation:
Ed 2022
The amount of potential energy possessed by an elevated object is:.
why is an iceberg more dense than a ship?
Answer:
icebergs float on water because ice is less dense than water. The same is true for a boat: a boat floats on water because, overall, it is less dense than the water.
Explanation:
A carrot has a mass of 69 grams and a volume of 150 cubic centimeters. Calculate its
density.
Answer:
As Per Provided Information
Mass of carrot 69 grams
Volume of carrot 150 cm³
we have been asked to determine the density of carrot .
Using Formulae
[tex] \bf \: Density = \cfrac{Mass \: of \: carrot}{Volume \: of \: carrot}[/tex]
Substituting the given value and let's solve it to determine the density of carrot.
[tex] \longrightarrow\sf \: Density = \cfrac{69}{150} \\ \\ \\ \longrightarrow\sf \: Density = \cancel\cfrac{69}{150} \\ \\ \\ \longrightarrow\sf \: Density =0.46 \: gm \: {cm}^{ - 3} [/tex]
Therefore,
Density of carrot is 0.46 gm/cm³If a number of coplanar forces acting on a particle are in equilibrium, then
Explanation:
Then the algebraic sum of the moment of all the forces about any point is equal to the moment of the resultant force about the same point
If a number of coplanar forces acting on a particle are in equilibrium. then the moment of their resultant is equal to the sum of their individual moment.
What is the law of moments?If a number of co-planar forces operating on a particle are in equilibrium, the algebraic sum of their moments about any point equals the moment of their resultant force about the same point, according to the law of moments.
Hence If a number of coplanar forces acting on a particle are in equilibrium. then the moment of their resultant is equal to the sum of their individual moment.
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What are radio isotopes??
Give one example of a radio isotope State one use too..
Don't spam..
Answer:
An isotope is one of two or more species of atoms of a chemical element with the same atomic number and position in the periodic table and nearly identical chemical behavior but with different atomic masses and physical properties. In medicine, for example, cobalt-60 is extensively employed as a radiation source to arrest the development of cancer. Other radioactive isotopes are used as tracers for diagnostic purposes as well as in research on metabolic processes.
Hope this helps! Please let me know if you need more help, or if you think my answer is incorrect. Brainliest would be MUCH appreciated. Have a wonderful day!
Those isotopes which are unstable due to the presence of extra neutrons in their nuclei and emit various types of radiations are called radioactive isotopes. The radiations emitted are in the form of alpha particles, beta particles and gamma rays.
For eg :- carbon,hydrogen and chlorine.
Hope it helps you!!I will be giving the brainliest to whoever.What is the PERCENT efficiency if a computer is supplied with 500 J of energy and is able to convert 400 J to useful energy?
A. 0.8 %
B. 8 %
C. 80 %
D. 800 %