b...radio waves answer
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1.Cell phones convert sound waves into______waves.
-light waves
-sound waves
-radio waves
2.Electromagnetic waves used in cell phone communications are called?
-microwave
-radio wave
-infrared
-all of the above
3.To send out a radio signal far and wide...it is called?
-broadcast
-casting
-antenna
Answer:
answer my question
Explanation:
Georgia drops a brick from the top of an 80.0 m building. What is the velocity of the brick when it hits the ground?
Answer:
the velocity of the brick when it hits the ground is 39.60 m/s
Explanation:
Given;
height through which the ball is dropped, h = 80.0 m
the initial velocity of the brick, u = 0
The final velocity of the brick when it hits the ground is calculated as;
v² = u² + 2gh
v² = 0 + 2 x 9.8 x 80
v² = 1568
v = √1568
v = 39.60 m/s
Therefore, the velocity of the brick when it hits the ground is 39.60 m/s
A boat has a porthole window, of area 0.00849 m^2, 6.25 m below the surface. The density of sea water is 1027 kg/m^3. The air inside the boat is at 1 atm. What is the net force on the window?
Answer:
[tex]325.65\ \text{N}[/tex] outward.
Explanation:
[tex]\rho[/tex] = Density of water = [tex]1027\ \text{kg/m}^3[/tex]
g = Acceleration due to gravity = [tex]9.81\ \text{m/s}^2[/tex]
h = Height of the water = 6.25 m
A = Area of the window = [tex]0.00849\ \text{m}^2[/tex]
[tex]P_i[/tex] = Internal pressure of the boat = [tex]1\ \text{atm}=101325\ \text{Pa}[/tex]
Pressure by the water on the window
[tex]P=\rho gh\\\Rightarrow P=1027\times 9.81\times 6.25\\\Rightarrow P=62967.9375\ \text{Pa}[/tex]
Net pressure on the window
[tex]P_n=P-P_i=62967.9375-101325=-38357.0625\ \text{Pa}[/tex]
Force is given by
[tex]F=P_nA\\\Rightarrow F=-38357.0625\times 0.00849\\\Rightarrow F=-325.651460625\ \text{N}[/tex]
Net force on the window is [tex]325.65\ \text{N}[/tex] outward.
Answer: 534.6 N
Explanation:
This answer works for Acellus!
Please hurry please
What is the height of the counter where a 4 kg fruit basket sits that has 30 J of gravitational potential energy? h= GPE/am
Answer:
0.765m
Explanation:
gravitational potential energy GPE = mass * acceleration due to gravity * height
Given
GPE = 30Joules
Mass m = 4kg
acceleration = 9.8m/s²
Required
Height h
From the formula
h = GPE/mg
h = 30/4(9.8)
h = 30/39.2
h = 0.765m\
Hence the height of the counter is 0.765m
The frequency of the wave is 0.4 Hz. Calculate the period.
Answer:
use the formula
Explanation:
F = 1/T
where F = frequency and T = period
so put 0.4 Hz into the frequency
0.4 =1/T
T = 2.5 seconds
hope this helps
According to Newton’s third law of motion, when a hammer strikes and exerts force on a nail, the nail...
A)creates a friction with the hammer
B) disappears into the wood
C) exerts an equal force back on the hammer
D) moves at a constant speed
Answer:
C) Exert an equal force back on the hammer
Explanation:
Every action has an equal and opposite reaction
also just trust me.
Make me brainlist
Robert hook used an early microscope to observed a cork sample. How did this help contribute to cell theory?
Answer:
Robert Hooke used an early microscope to observe a cork sample. How did this help contribute to cell theory? It helped to show that cells contain water. ... It helped to show that some cells are visible to the naked eye.
Explanation:
If your teacher checks if it was copied just put it in your on words
Consider the common measurement speed = 55 mph. What is the magnitude quantity?
Speed, mph, miles per hour, 55
Answer:
Magnitude = 55
Quantity = Speed
Explanation:
We are told that the speed is 55 mph. This implies that the magnitude is 55 while the unit is mph.
Also, physical quantities are usually things that can be measured such as distance, voltage, temperature e.t.c
Answer:
i think its speed
Explanation:
PLS ANSWER FAST WILL GIVE BRAINLY TIMED TEST
use the equation solving a= F divided by M
Also use metres per second squared [m/s2]
A loaded coal wagon with a total mass of 20, 000 kg is pushed by a force of 300,000 N. What was the wagon's acceleration?
A 5 Kg bowling ball is thrown at a stationary 1.6 Kg bowling pin at 5 m/s. If the final velocity of the ball is 2.5 m/s. The final velicoty of the bowling pin is _____m/s.
Answer: hope this helps
Explanation:
If the final velocity of the ball is 2.5 m/s, the final velocity of the bowling pin is 7.8125 m/s.
What is principle of conservation of momentum?According to the principle of momentum conservation, momentum is only modified by the action of forces as they are outlined by Newton's equations of motion; momentum is never created nor destroyed inside a problem domain.
According to the principle of momentum conservation, total momentum of an system remains conserved.
Total initial momentum = total final momentum
5 kg × 5 m/s + 1.6 kg × 0 m/s = 5 kg × 2.5 m/s + 1.6 kg × v
1.6 kg × v = 5 kg × 5 m/s - 5 kg × 2.5 m/s
v = (5 kg /1.6 kg) (5 m/s - 2.5 m/s)
= 7.8125 m/s
Hence, If the final velocity of the ball is 2.5 m/s, the final velocity of the bowling pin is 7.8125 m/s.
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Based on its position in the periodic table of the elements, how many valence electrons does phosphorus (atomic number 15) have?
Answer:
5 Valence electrons
Explanation:
Answer:
5 Valence electrons
Explanation:
Hope this will help
Stored digital data are easily changed. How could this be a disadvantage?
A. Changing data results in too much data to be stored in most
computers
B. Easily changed data are difficult to protect with a security system.
c. Once a change is made, the change is permanent.
D. True information in the digital data can be changed to false
information
SUBMIT
I need help on this
The disadvantage of easily changeable digital data is: true information in the digital data can be changed to false information. Hence, option (D) is correct.
What is digital data?Digital data, in information theory and information systems, is information represented as a string of discrete symbols, each of which can take on one of only a finite number of values from some alphabet, such as letters or digits.
An example is a text document, which consists of a string of alphanumeric characters. The most common form of digital data in modern information systems is binary data.
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Answer: The answer is D.
Explanation: I took the test
Skater begins to spend with arms held out at shoulder height. The skater wants to match the speed of the spin to the beat of the music. How does the skater use knowledge of the conservation of momentum to do this?
Answer:
the moment of inertia with the arms extended is Io and when the arms are lowered the moment
I₀/I > 1 ⇒ w > w₀
Explanation:
The angular momentum is conserved if the external torques in the system are zero, this is achieved because the friction with the ice is very small,
L₀ = L_f
I₀ w₀ = I w
w =[tex]\frac{I_o}{I}[/tex] w₀
where we see that the angular velocity changes according to the relation of the angular moments, if we approximate the body as a cylinder with two point charges, weight of the arms
I₀ = I_cylinder + 2 m r²
where r is the distance from the center of mass of the arms to the axis of rotation, the moment of inertia of the cylinder does not change, therefore changing the distance of the arms changes the moment of inertia.
If we say that the moment of inertia with the arms extended is Io and when the arms are lowered the moment will be
I <I₀
I₀/I > 1 ⇒ w > w₀
therefore the angular velocity (rotations) must increase
in this way the skater can adjust his spin speed to the musician.
which
In describing the motion of an object it is often helpful to identify a
allows you to describe its motion relative to that of another object.
O acceleration
O average velocity
O frame of reference
O speed
En pocas palabras la utilidad que le darias al hecho de conocer los principios y leyes que rigen el movimiento de los cuerpos
Answer:
we can predict where they are in the future, know where they were in the past
can also build a device that generates a specific type of desired movement,
Explanation:
With the knowledge of the laws that govern the movement of bodies, we can predict where they are in the future and therefore know if there may be an accident, crash.
We can also know where they were in the past and therefore know if a fact is the result of these movements, craters, collapse of buildings, etc.
We can also build a device that generates a specific type of desired movement, for example pulleys that help us with work, etc.
From base camp, a park ranger drives 27 meters at 32 degrees East of North, then 40 meters at 58 degrees West of North, and finally 39 meters directly West in an attempt to rescue a lost hiker.
Answer:
R = 73.34 m, θ = 37º North of West
Explanation:
In this exercise you are asked to find the distance traveled.
The best way to do this is with a Cartesian coordinate system, let's use a system where the x axis coincides with the West - East direction), to decompose the trajectories
First trajectory
distance d₁ = 27 m
Direction 32 East of North, this angle is measured from the vertical direction (y-axis)
cos 32 = y₁ / d₁
sin 32 = x₁ / d₁
y₁ = d₁ cos 32
x₁ = d₁ sin 32
y₁ = 27 cos 32 = 22.90 m
x₁ = 27 sin 32 = 14.31 m
second trajectories
distance d2 = 40 m
direction 58 West from North, the angle is measured with respect to the y axis, towards the negative side of the x axis
cos 58 = y₂ / d₂
sin 32 = x₂ / d₂
y₂ = d₂ cos58
x₂ = d₂ sin 58
y₂ = 40 cos 58 = 21.20 m
x₂ = 40 sin 58 = -33.92 m
The negative sign of the x coordinate is due to the fact that the displacement is towards the West (negative of the x axis)
third trajectory
distance d₃ = 39 m
West direction, negative part of x-axis
x₃ = - 39 m
the total distance is
= x₁ + x₂ + x₃
X_{total}l = 14.30 - 33.92 -39
X_{total}X_total = -58.6 m
Y_{total} = y₁ + y₂
Y_{total}= 22.90 + 21.20
Y_{total} = 44.1 m
we give the result in the form of module and angle
we use the Pythagorean theorem
R = [tex]\sqrt{X_{total}^2 + Y_{total}^2 }[/tex]
R =\sqrt58.6^2 + 44.1^2 }
R = 73.34 m
we use trigonometry
tan θ =
θ = tan⁻¹ \frac{ Y_{total} }{ X_{total} }
θ = tan⁻¹ \frac{ 44.1 }{ 58.6 } (44.1 / 58.6)
θ = -37º
this angle is in the second quadrant, given in the form of cardinal coordinates is
θ = 37º North of West
How much heat energy is given out when 500g of steam at 100 degrees celcius condenses to water at 100 degrees celcius
Explanation:
How much thermal energy is released when 500g of steam at 100° C condenses into water and cools to 50°C
Givens: m=0.5 kg
t = 50
c = 2.010
Qtotal = Q1 + Q2
Qtotal = QmcΔt + mLv
Qtotal = (0.5kg)(2.010)(50) + (0.5)(2.3*10^6)
Qtotal = 1.15 * 10^6
The book says that the answer is 1.3*10^6?
What did I do wrong here?
A raindrop falls from a cloud 100 m above the ground. Neglect air resistance. What is
the speed of the raindrop when it hits the ground? Is this a reasonable number? Explain.
Answer:
Explanation:
Use the kinematic equation
[tex]V^2=V^2_i+2a(x_f-x_i)[/tex]
The initial velocity was given from the word "falls." Acceleration due to gravity is 9.8 m/s^2.
[tex]V^2=0^2+200(9.8)[/tex]
[tex]V=\sqrt{1960} =44.27m/s[/tex]
A raindrop falls from a cloud 100 m above the ground. Neglect air resistance. The speed of the raindrop when it hits the ground would be 44.27 meters/ second.
What is mechanical energy?The sum of all the energy in motion (total kinetic energy) and all the energy that is stored in the system (total potential energy) is known as mechanical energy.
As given in the problem A raindrop falls from a cloud 100 m above the ground. Neglect air resistance, then we have to find out the speed of the raindrop when it hits the ground,
The speed of the raindrop = √(2gh)
=√(2*9.8*100)
=44.27 meters/seconds
Thus, if a raindrop falls from a cloud 100 m above the ground. Neglect air resistance. the speed of the raindrop when it hits the ground would be 44.27 meters/ second.
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The odometer of a car reads 57321 km when the clock shows the time 8.30 am. What is the distance moved by the car, if at 8.50 am, the odometer reading has changed to 57336.0 km? Calculate the speed of the car in km/min during this time.
Answer:
0.75km/min
Explanation:
I haven't learnt physics at all but I'll try
57336 - 57321 = 15km (Difference)
8.50 am - 8.30 am = 20 minutes (Difference)
If the car odometer adds up 15km every 20 minutes...
20 mins = 15km
1 min = 15 ÷ 20 = 0.75km
What part of the eye protects your eye from scratches?
retina
pupil
cornea
iris
Answer:
Cornea
Explanation:
The outer layer of the cornea is covered by epithelial cells that protect the surface. A corneal abrasion may result from dragging a piece of debris across the surface and scraping off the epithelial cells.
3. Why is static electricity not useful as a power
source?
A. Because electrons aren't transferred in bursts of
static electricity
B. Because all energy is released at once in static
electricity
C. Because static electricity is not a real form of
electricity
D. Because static electricity only occurs in lightning
Static electricity is not useful as a power source primarily because it releases all of its energy at once rather than providing a continuous and controlled flow of electrical energy. The correct answer is B.
When static electricity is discharged, such as in a spark or a sudden discharge of stored charge, it happens in a rapid and uncontrolled manner, resulting in a brief burst of energy rather than a steady and sustained flow.
Power sources typically require a continuous and controllable flow of electrical energy to be useful for various applications. Static electricity, in its nature, does not provide this continuous flow but instead releases energy in an instantaneous manner. Therefore, it is not suitable for most practical power needs and applications.
Option A is not correct because electrons can be transferred in bursts of static electricity. Option C is not correct because static electricity is a real form of electricity, even though it has unique characteristics. Option D is not correct because static electricity can occur in various circumstances, not just in lightning.
Therefore, Static electricity is not useful as a power source primarily because it releases all of its energy at once rather than providing a continuous and controlled flow of electrical energy. The correct answer is B.
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How much force must be applied to a 4 kg to get it to accelerate at 3
m/s^2?
Answer:
12 g i think
Explanation:
brainliest pls
James is planning a science fair project on sound waves. He places an alarm inside a jar which he can remove the
air from. Before he removes the air, he can hear the alarm ringing. After he removes the alr, he cannot hear the
alarm ringing. What condusion can you draw from this experiment?
A. Sound waves can travel in a vacuum
B. Sound waves are transverse waves and are loud
C. Sound waves cannot travel through a medium
D. Sound waves require a medium to travel through
Answer: c
Explanation:
Sound waves cannot travel through a medium
6. Abdul moves a magnetic toy train away from a magnet that cannot move. What happens to the
potential energy in the system of magnets during the movement?
a
The potential energy decreases because the train moves in the same direction as the
magnetic force.
b
The potential energy decreases because the train moves against the magnetic force.
С
The potential energy increases because the train moves against the magnetic force.
d
The potential energy does not change because the magnets in the system do not change.
Yeah
Answer: Potential energy increases because the train moves against the magnetic force.
Explanation:
When the magnetic toy train is moved away from a magnet that cannot move, the potential energy in the system of magnets during the movement is affected as there's an increase in the potential energy because the train moves against the magnetic force.
We should note that the potential energy simply means the energy that is stored in the magnetic toy. Since the magnetic toy has been moved away from the magnet, the likelihood of its attraction will reduce thereby there'll be a rise in the potential energy.
A book is sitting on the dashboard of a car that is stopped at a traffic light as the car starts to move forward the book slides backward off the dashboard what does the book actually do
Answer:
The book remained in its state of rest before the car started to move forward as no direct force acted on it.
Explanation:
According to Newton's first law of motion, a body will continue in its present state of rest, or if it is in motion, will continue to move with uniform speed in a straight line unless aced upon by an external force. This tendency of a body to remain in its state of reset or uniform motion in a straight line is known as inertia and is directly proportional to the mass of the body. The more massive a body, the more inertia it possesses. Thus Newton's first law is also known as the law of inertia.
Considering the case of the book on the dashboard of a stationary car which suddenly starts to move. While the car is stopped at the traffic light, the dashboard where the book sits and the book are both at rest. When the car begins to move forward, the dashboard moves forward with it. However as the book is not a part of the car, no force is directly acting on it, so the book so it stays at rest due to its inertia.
Therefore, as the car is moving forward, the stationary book appears to move backward from the reference point of the car, sliding off the dashboard.
What is the change in internal energy if a gas loses 80 joules of heat, and then does 60
joules of work?
Answer:
-140
Explanation:
A gas loses 80joules of heat.
The gas also does 60 joules of work
Therefore the change in internal energy can be calculated as follows
= -80 + (-60)
= -80-60
= -140
Hence the change in internal energy is -140
During a contest that involved throwing a 7.0-kg bowling ball straight up in the air, one contestant exerted a force of 810 N on the ball. If the force was exerted through a distance of 2.0 m, how high did the ball go from the point of release?
Answer:
23.6 m
Explanation:
We are given that
Mass of ball, m=7.0 kg
Force, F=810 N
Distance, s=2.0 m
We have to find the height of ball from the point where it releases.
Work done=K.E
[tex]Fs=\frac{1}{2}mv^2[/tex]
[tex]v^2=\frac{2Fs}{m}[/tex]
Substitute the value
[tex]v^2=\frac{2\times 810\times 2}{7}[/tex]
[tex]v^2=\frac{3240}{7}[/tex]
K.E=P.E
[tex]\frac{1}{2}mv^2=mgh[/tex]
[tex]\frac{1}{2}v^2=gh[/tex]
Where g=[tex]9.8m/s^2[/tex]
[tex]\frac{1}{2}\times \frac{3240}{7}=9.8h[/tex]
[tex]h=\frac{3240}{7\times 2\times 9.8}[/tex]
[tex]h=23.6 m[/tex]
What is the netforce?
Answer:
6 Newtons to the left.
Explanation:
We can convert this into a generic algebra equation by giving directions positive and negative values.
The 6 will be positive, and the 10 and 2 will be negative.
Add 10 and 2 to have 12.
6-12 = -6.
Therefore you have 6 newtons to the left (negative).
how do you fix a broken foot
my sister is in literal tears and i dont have a phone and
our parents are out of the house rn
on what mass will a force 16N produce an acceleration of 160N
Answer:
m = 0.1 [kg]
Explanation:
To solve this problem we must use Newton's second law, which tells us that the sum of forces on a body is equal to the product of mass by acceleration. In this way, we have the following equation.
[tex]F =m*a[/tex]
where:
F = force = 16[N]
a = acceleration = 160 [m/s²]
m = mass [kg]
Now replacing:
[tex]m=F/a\\m = 16/160\\m = 0.1 [kg][/tex]