Answer:
a
[tex]t = 3.33 \ ns[/tex]
b
i [tex]D_w =0.75 \ m [/tex]
ii [tex]D_g =0.67 \ m [/tex]
iii [tex]D_c =0.46 \ m [/tex]
Explanation:
Generally the time taken to travel 1 m in a vacuum is mathematically represented as
[tex]t = \frac{1}{c}[/tex]
Here c is the speed of light with value [tex]c = 3.0*10^{8} \ m/s[/tex]
So
[tex]t = \frac{1}{3.0*10^{8}}[/tex]
[tex]t = 3.33*10^{-9} \ s[/tex]
[tex]t = 3.33 \ ns[/tex]
The distance light travels in water is mathematically represented as
[tex]D_w = \frac{c}{n_w} * t[/tex]
Here n_w is the refractive index of water with value 1.333
So
[tex]D_w = \frac{3.0*10^{8}}{1.333} * 3.33*10^{-9}[/tex]
[tex]D_w =0.75 \ m [/tex]
The distance light travels in glass is mathematically represented as
[tex]D_g = \frac{c}{n_g} * t[/tex]
Here n_g is the refractive index of glass with value 1.5
So
[tex]D_g = \frac{3.0*10^{8}}{1.5} * 3.33*10^{-9}[/tex]
[tex]D_g =0.67 \ m [/tex]
The distance light travels in cubic zirconia is mathematically represented as
[tex]D_c = \frac{c}{n_g} * t[/tex]
Here n_c is the refractive index of cubic zirconia with value 2.15
So
[tex]D_c = \frac{3.0*10^{8}}{2.15} * 3.33*10^{-9}[/tex]
[tex]D_c =0.46 \ m [/tex]
To understand the decibel scale. The decibel scale is a logarithmic scale for measuring the sound intensity level. Because the decibel scale is logarithmic, it changes by an additive constant when the intensity as measured in W/m2 changes by a multiplicative factor. The number of decibels increases by 10 for a factor of 10 increase in intensity. The general formula for the sound intensity level, in decibels, corresponding to intensity I is
The question is incomplete. Here is the complete question.
To understand the decibel scale. The decibel scale is a logarithmic scale for measuring the sound intensity level. Because the decibel scale is logarithmic, it changes by an additive constant when the intensity when the intensity as measured in W/m² changes by a multiplicative factor. The number of decibels increase by 10 for a factor of 10 increase in intensity. The general formula for the sound intensity level, in decibels, corresponding to intensity I is
[tex]\beta=10log(\frac{I}{I_{0}} )dB[/tex],
where [tex]I_{0}[/tex] is a reference intensity. for sound waves, [tex]I_{0}[/tex] is taken to be [tex]10^{-12} W/m^{2}[/tex]. Note that log refers to the logarithm to the base 10.
Part A: What is the sound intensity level β, in decibels, of a sound wave whose intensity is 10 times the reference intensity, i.e. [tex]I=10I_{0}[/tex]? Express the sound intensity numerically to the nearest integer.
Part B: What is the sound intensity level β, in decibels, of a sound wave whose intensity is 100 times the reference intensity, i.e. [tex]I=100I_{0}[/tex]? Express the sound intensity numerically to the nearest integer.
Part C: Calculate the change in decibels ([tex]\Delta \beta_{2},\Delta \beta_{4}[/tex] and [tex]\Delta \beta_{8}[/tex]) corresponding to f = 2, f = 4 and f = 8. Give your answer, separated by commas, to the nearest integer -- this will give an accuracy of 20%, which is good enough for sound.
Answer and Explanation: Using the formula for sound intensity level:
A) [tex]I=10I_{0}[/tex]
[tex]\beta=10log(\frac{10I_{0}}{I_{0}} )[/tex]
[tex]\beta=10log(10 )[/tex]
β = 10
The sound Intensity level with intensity 10x is 10dB.
B) [tex]I=100I_{0}[/tex]
[tex]\beta=10log(\frac{100I_{0}}{I_{0}} )[/tex]
[tex]\beta=10log(100)[/tex]
β = 20
With intensity 100x, level is 20dB.
C) To calculate the change, take the f to be the factor of increase:
For [tex]\Delta \beta_{2}[/tex]:
[tex]I=2I_{0}[/tex]
[tex]\beta=10log(\frac{2I_{0}}{I_{0}} )[/tex]
[tex]\beta=10log(2)[/tex]
β = 3
For [tex]\Delta \beta_{4}[/tex]:
[tex]I=4I_{0}[/tex]
[tex]\beta=10log(\frac{4I_{0}}{I_{0}} )[/tex]
[tex]\beta=10log(4)[/tex]
β = 6
For [tex]\Delta \beta_{8}[/tex]:
[tex]I=8I_{0}[/tex]
[tex]\beta=10log(\frac{8I_{0}}{I_{0}} )[/tex]
β = 9
Change is
[tex]\Delta \beta_{2},\Delta \beta_{4}[/tex], [tex]\Delta \beta_{8}[/tex] = 3,6,9 dB
A simple model of a hydrogen atom is a positive point charge +e (representing the proton) at the center of a ring of radius a with negative charge −e distributed uniformly around the ring (representing the electron in orbit around the proton). Find the magnitude of the total electric field due to this charge distribution at a point a distance a from the proton and perpendicular to the plane of the ring.
Answer:
Now e is due to the ring at a
So
We say
1/4πEo(ea/ a²+a²)^3/2
= 1/4πEo ea/2√2a³
So here E is faced towards the ring
Next is E due to a point at the centre
So
E² = 1/4πEo ( e/a²)
Finally we get the total
Et= E²-E
= e/4πEo(2√2-1/2√2)
So the direction here is away from the ring
Ricardo finds an online site about the gas laws. The site shows the equation below for Charles’s law. What change would correct the error on the site? “Charles’s law” should read “Gay-Lussac’s law,” which explains changes in volume and temperature. The symbol for T2 should be smaller than for T1 because if volume increases, then temperature should decrease. Each T should be replaced by a P in the equation because Charles’s law describes changes in volume and pressure. The volume should be divided by temperature on each side of the equation.
Answer:
D. The volume should be divided by temperature on each side of the equation.
Explanation:
Charles's Law is [tex]\frac{V_{1} }{T_{1} } = \frac{V_{2} }{T_{2} }[/tex].
Answer:
The volume should be divided by temperature on each side of the equation.
Explanation:
What the differences between static and kinetic friction?
Answer:
Static friction prevents a stationary object from moving while kinetic or dynamic friction slows down a moving object.
Explanation:
Static Friction is the maximum force that must be overcome before a stationary object begins to move, while kinetic or dynamic friction is the maximum force that must be overcome for an object in motion to continue moving at a uniform velocity.
Static friction keeps a stationary object at rest, once the Force of Static friction is overcome, the Force of Kinetic friction is what slows down the moving object.
How does the energy in matter affect the state?
Answer:
Because of melting and freezing a higher heat will make something a plasma or liquid by melting it. by freezing you can make a liquid or gas solid.
Explanation:
a cart travels 3.00 meters east and then 4.00 meters north. the magnitude
Answer: 5 m
Explanation:
X^2= 9+16
X = 5
According to pythagoras law
Which phenomenon related to light allows scientists to measure the distance between a star and Earth? A. Dark patches appear in the electromagnetic spectrum emitted by stars. B. Light waves spread out as they move farther from their source. C. Stars have different colors based on their temperature. D. Stars have unique elements that make up their atmospheres.
Answer:
The Answer Is B not C
Explanation:
Answer:b
Explanation:
What is the frequency in Hz of a wave that travels at 2,500 m/s with a wavelength of 100 m?
Answer:
f = 25 Hz
Explanation:
We know that :
[tex]v = f*d\\=> f = \frac{v}{d}[/tex] where f = frequency ; v = speed & d = wavelength
Here in the question ,
Speed = 2500 m/s
Wavelength = 100 m
Using the above formula ,
Frequency = [tex]\frac{2500}{100} = 25 Hz[/tex]
This ball is technology too! It can be
rolled, kicked, or thrown. Is that a need
or a want?
Answer:
want
Explanation:
people always want the new thing especially if its technology
A large negatively charged object is placed on a wooden table. A neutral metallic ball rolls straight towards the object but stops before it touches it. A second neutral metallic ball rolls up along the path followed by the first ball, strikes the first ball driving it a bit closer to the negatively charged object and stops. After all balls have stopped rolling, the first ball is closer to the negatively charged object than is the second ball. At no time did either ball touch the charged object. Which statement is correct concerning the final charge on each ball
Answer:
the charge of each small sphere, which is + Q / 2
Explanation:
For this exercise we must use the fact that a charged object induces charges on nearby bodies
Induced charge comes from the fact that charges of the same sign repel and charges of different signs attract.
In this case the large, fixed ball with a -Q charge induces a positive charge in the nearest part and the negative charges are repelled to the furthest point, but the net charge on the metallic sphere remains zero. It should be emphasized that since the charges are of different signs, there is an attractive force between the two spheres.
This first metallic sphere now has a negative charge on the back, this charge induces a positive charge on the second sphere, as the charges are of a different sign, they attract each other, which is why the force is attractive.
When the first sphere stops the second sphere hits it, at this moment the charge of the two spheres is equal, therefore the induced charge in the two spheres is + Q. When the two spheres are separated, the charge on each of them is half, that is, the sphere has a charge + Q / 2 and the second sphere has a charge + Q / 2.
Therefore the first sphere is subjected to two forces: an attractive force with the large sphere of charge -Q and a repulsive force with the second sphere of charge + Q / 2.
So the first sphere must approach the big ball and the second sphere must move away from the big sphere.
This is the process of the movement of this exercise, unfortunately the statements with which to compare this process do not appear, but one of the most common questions of what is the charge of each small sphere, which is + Q / 2
A fisherman’s boat moves up and down periodically due to water waves. The boat travels from its highest to its lowest point, a vertical distance of 0.60 m, in 2.0 s. The horizontal distance between wave crests is 7.0 m. (a) What is the period of the wave motion? (b) What is the frequency of the wave motion? (c) W
Complete question is;
A fisherman’s boat moves up and down periodically due to water waves. The boat travels from its highest to its lowest point, a vertical distance of 0.60 m, in 2.0 s. The horizontal distance between wave crests is 7.0 m. (a) What is the period of the wave motion? (b) What is the frequency of the wave motion? (c) What is the amplitude of each wave
Answer:
A) Period = 4 s
B) Frequency = 0.25 Hz
C) Amplitude = 0.3 m
Explanation:
A) We are told that the distance it takes for the boat to travel from its highest to its lowest point is 2 s.
Thus, t = 2 s
Now, in waves, period (T) it the time between two successive waves.
This means that;
T = 2t
T = 2 × 2
T = 4 s
B) Also, the frequency(f) is given by the formula;
f = 1/T
f = 1/4
f = 0.25 Hz
C) We are given a vertical distance of 0.60 m from highest to lowest point of waves.
Now, amplitude is half of this distance.
Thus;
Amplitude(A) = 0.6/2
A = 0.3 m
Sally walks to the store at a rate of 3 m/s for 15 seconds. She stops at a crosswalk for 4 seconds until the sign tells her she can go. Sally ran across the street at 5 m/s for 3 seconds until she reached the other side. She then walked the rest of the way to the store at 3 m/s. If the store was 100 m away from where Sally started originally and it took her 250 seconds to get there, what was her average speed?
Answer:
Average speed= 0.4 m/sExplanation:
step one:
simply put average speed is defined as the total distance travelled divided by the total time taken.
step two:
given data
total distance is the distance from where she started to the store
which is 100 m
also, we are told that the total time taken is 250 seconds
step three:
Hence we can compute the average speed as
average speed= 100/250
average speed= 0.4 m/s
What is 902 in proper scientific notation?
where do plants get the energy they need for photosynthesis
(A) leaves
(B) the sun
(C) sugars
(D) water
they get their energy from photosynthesis, so the answer would be (B) the sun
Which inference about Arthur is supported by the text?
A ball with mass kg is thrown upward with initial velocity m/s from the roof of a building m high. Neglect air resistance. Use m/s2. Round your answers to one decimal place. (a) Find the maximum height above the ground that the ball reaches. meters (b) Assuming that the ball misses the building on the way down, find the time that it hits the ground. s
Answer:
Explanation:
The question is incomplete. Here is the complete question.
A ball with mass m kg is thrown upward with initial velocity 22 m/s from the roof of a building 17 m high. Neglect air resistance. Use g=9.8 m/s2. Round your answers to one decimal place. (a) Find the maximum height above the ground that the ball reaches. xmax= meters (b) Assuming that the ball misses the building on the way down, find the time that it hits the ground.
a) Using the equation of motion formula;
v² = u²+2gH where;
u is the initial velocity
v is the final velocity
theta is the angle of launch
g is the acceleration due to gravity.
H is the maximum height reached by the ball
Since the ball is thrown upwards, the acceleration due to gravity will be negative. The equation then becomes;
v² = u²-2gH
Given
v = 0m/s
u = 22m/s
g = 9.8m.s²
0² = 22²-2(9.8)H
-22² = -19.6H
H = -22²/-19.6
H = 24.69m
If the biuliding is 17m high, the maximum height above the ground that the ball reaches will be;
Hmax = 24.69+17
Hmax = 41.69m
b) The time it takes to hit the ground can be expressed using the formula
v = u-gt
0 = 22-9.8t
-22 = -9.8t
t = -22/9.8
t = 2.45secs
is it true or false if a force is a push or a pull on a object
Answer: true
Explanation: a force can be anything that effects an object, as long as the object moves
Father drove 176 km in 7 hours. For the first 92 km, he spent
for 4 hours. What was his average speed for the remaining
journey?
km/h
Answer:
28km/h
Explanation:
92km = 4 hours
176 - 92 = 84
84km = 3 hours
84/3 = 28
28km/h
Hopefully this helps you :)
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4. Two people each have a mass of 55 kg. They are both in an
elevator that has a mass of 240 kg. When the elevator
begins to move, the people and the elevator have an upward
acceleration of 1.00 m/s2. What is the net force that acts on
the elevator as it accelerates upward at 1.00 m/s2?
Answer:
350 N
Explanation:
F=ma
[tex]f = force \\ m = mass \\ a = acceleration[/tex]
[tex]m = 2(55kg) + 240kg \\ a = 1.0 \frac{m}{ {s}^{2} } [/tex]
Force = 350 Newtons
The net force acting on the elevator would be 350 Newtons as it accelerates upward at 1.00 m/s2.
What is Newton's second law?
Newton's Second Law states that The resultant force acting on an object is proportional to the rate of change of momentum.
The mathematical expression for Newton's second law is as follows
F = ma
As given in the problem two people each have a mass of 55 kg. They are both in an elevator that has a mass of 240 kg. When the elevator begins to move, the people and the elevator have an upward acceleration of 1.00 m/s2, then we have to find the net force acting on the elevator,
The net force acting on the elevator,
F = ma
F =(2×55 + 240)×1
= 350 Newtons
Thus, the net force acting on the elevator would be 350 Newtons as it accelerates upward at 1.00 m/s2
Learn more about Newton's second law, here
brainly.com/question/13447525
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the force which slow down a paper aeroplane moving through the air is called
The paper plane slows down when flying in the air due to air resistance or the friction due to the air around it. As the paper plane have flat surfaces and more surface area, the air resists it's motion more than before. If the paper plane is moving towards left, then friction acts towards left.
The friction always act opposite to the direction of paper plane and resists its motion. Hence, we can say that paper plane slows due to Frictional Force [tex]\red{\bullet}[/tex]
#CarryOnLearning
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Which is the process by which a solid changes to a liquid? O condensation O evaporation O melting sublimation
Answer:
Melting
Explanation:
The process in which a solid changes to a liquid is called melting. This process is also termed as fusion. Due to application of heat and pressure, the internal energy of a solid increases and the molecules become far from each other due to which it starts to melt.
Hence, the correct option is (c) "melting".
Answer:
c. melting
Explanation:
took the quiz on edge
The bonds between molecules store ____ Energy?
Answer:
chemical energy
Explanation:
Answer:
chemical energy
Explanation:
Energy is also stored in the covalent bonds holding atoms together in molecules. ... the difference in the amount of free energy given off as the original, reacting molecules fly apart, and the amount of free energy absorbed as the new covalent bonds form is left in the environment, often as light and/or heat.
Two point charges are on the x-axis. One charge, q1 = 10 nC, is located at the origin, and the othercharge, q2 = 18 nC, is located at x = 9.0 m. What is the force on q2?a) 20 nN in the positive x-directionb) 20 pN in the positive x-directionc) 20 nN in the negative x-directiond) 20 pN in the negative x-directione) 180 nN in the positive x-direction
Answer:
The correct option is A
Explanation:
Generally the force on [tex]q_2[/tex] is mathematically represented as
[tex]F_2 = \frac{ k * q_1 * q_2 }{ x^2}[/tex]
here k is the coulombs constant with value [tex]k = 9*10^{9}\ kg\cdot m^3\cdot s^{-4} \cdot A^{-2}.[/tex]
=> [tex]F_2 = \frac{ 9*10^{9} * 10*10^{-9} * 18*10^{-9} }{ 9^2}[/tex]
=> [tex]F_2 = 2*10^{-8} \ N[/tex]
=> [tex]F_2 = 20*10^{-9} \ N[/tex]
=> [tex]F_2 = 20nN[/tex]
The direction is in the positive x-axis because both charge are of the same polarity so the will repel hence [tex]q_2[/tex] will move toward the positive x-axis
An automobile is driven on a straight road, and the distance traveled by the automobile after time t=0 is given by a quadratic function a where a(t) is measured in feet and t is measured in seconds for 0 <= t <= 12. Of the following, which gives the best estimate of the velocity of the automobile, in feet per second, at time t = 8 seconds?
a. s(8)
b. s(8)/8
c. s(12)- s(2)/ 12-2
d. s(9)- s(7)/9-7
Answer:
[tex]Velocity = \frac{s(8)}{8}[/tex]
Explanation:
Given
[tex]0 \leq t \leq 12[/tex]
Required
Determine the velocity when t = 8
This type of velocity is referred to as an instantaneous velocity.
In this case, it is calculated using
[tex]Velocity = \frac{Distance\ at\ 8 second}{t = 8}[/tex]
Given that s(t) models the distance;
s(8) = distance at 8 seconds
So;
[tex]Velocity = \frac{s(8)}{8}[/tex]
Option B answers the question
What is the speed of an object that travels 60 meters in 4 seconds?
Answer:
15 m/s
Explanation:
s=d/t
s=60/4
s=15 m/s
Answer:
The answer would be 15 m/s
Explanation:
s=d/t
s=60/4
s= 15 m/s
Have a beautiful day beautiful
You welcome.
Q17: A quantity has a unit of Kg.m-1.s-1, then its dimension is:
(a) [M2 L2 T?]
(b) M L?T
(c) (M2 LT]
(d) [M L-1 T-1]
(e) [M L-11-2]
Answer:
It's dimension is (d) [M L-1 T-1]
iv. When you use a hand pump to inflate the tires of your bicycle, the pump gets warm after a while. Why? What happens to the temperature of the air in the pump as you compress it? Why does this happen? When you raise the pump handle to draw outside air into the pump, what happens to the temperature of the air taken in? Again, why does this happen?reason
Answer:
The temperature rises because for a given volume of gas, a rise pressure of the gas in pressure results in a proportionate rise in the temperature of the gas
Similarly when the handle is raised to draw air causes a fall in pressure that results in proportionate fall in temperature, for a given volume of gas
Explanation:
From Gay-Lussac's law, states that the pressure of a given mass of gas is directly proportional to its Kelvin temperature, provided that the volume is held constant
Mathematically, the law states that Pressure ∝ Temperature, at constant Volume
Therefore;
P₁/T₁ = P₂/T₂
Similarly, by kinetic theory of gases, we have;
The
[tex]P = \dfrac{n \cdot MW \cdot v_{rms}^2}{3 \cdot V}[/tex]
[tex]v_{rms} = \sqrt{\dfrac{3 \cdot R \cdot T}{MW} }[/tex]
Therefore, as in order for the hand pump to inflate the bicycle tires, the air in the pump has to be compressed to force it into the tire, thereby increasing the pressure, of the air in a given volume of the pump which results in the raising of the temperature of the air in the pump, which raises the temperature of the wall of the pump.
The temperature of the air in the pump also falls as the pressure in the pump is reduced by raising the pump handle, to reduce the air pressure inside the pump and and allow air to be taken into the pump.
Which is not one of the basic nutrients of your body?
1.Vitamins
2.Minerals
3.Molecules
4.Protein
An external reward is known as extrinsic motivation.
ОА.
True
OB. False
Lizard: A lizard is running in a straight line according to the following: xx(tt) = tt3⁄3 − tt2 + tt He starts at tt = 0. (a) Determine vv(tt). (b) When is the lizard at rest? (c) When is the lizard moving in the positive xx direction? (d) When is the lizard moving in the negative xx direction? (e) When does the lizard have zero acceleration?
Answer:
Explanation:
a ) x ( t ) = t³ / 3 - t² + t
v = dx / dt = 3 t² / 3 - 2 t + 1 = t² - 2 t + 1
b ) lizard is at rest , v( t ) = 0
t² - 2 t + 1 = 0
( t - 1 )² = 0
t = 1
c )
velocity is positive when
t² - 2 t + 1 > 0
( t - 1 ) ² > 0
Here we see that LHS is a square so it is always positive whatever be the value of t
So velocity is always positive or lizard is always moving in positive x direction .
d ) It never moves in negative x direction .
e )
a ( t ) = dv / dt = 2t - 2
t = 1
so it has zero acceleration at t = 0 .