A boy of mass 60 kg is sledding down a 70 m slope starting from rest. The slope is angled at 15° below the horizontal. After going 20 m along the slope he passes his friend of mass 50 kg, who jumps on the sled. They now move together to the bottom of the slope. The coefficient of kinetic friction between the sled and the snow is 0.12. Ignoring the mass of the sled, find their speed at the bottom.
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help plz! what vibrates in following types of wave motion 1)light wave 2)sound waves 3)x-rays 4)water waves
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Answer:
I believe it's 2) sound waves
Explanation:
With sound waves, the energy travels along in the same direction as the particles vibrate. This type of wave is known as a longitudinal wave, so named because the energy travels along the direction of vibration of the particles.
To understand the relationships between the parameters that characterize a wave. It is of fundamental importance in many areas of physics to be able to deal with waves. This problem will lead you to understand the relationship of variables related to wave propagation: frequency, wavelength, velocity of propagation, and related variables. Note that these are kinematic variables that relate to the wave's propagation and do not depend on its amplitude.
1. Traveling waves propagate with a fixed speed usually denoted as v (but sometimes c). The waves are called __________ if their waveform repeats every time interval T.
a. transverse
b. longitudinal
c. periodic
d. sinusoidal
2. If the velocity of the wave remains constant, then as the frequency of the wave is increased, the wavelength __________.
a. decreases
b. increases
c. stays constant
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Answer:
1) c.
2) a.)
Explanation:
1)
At any wave, if its waveform repeats itself every time interval T, it is said that the wave is periodic, with a period T, which is the time needed to complete an entire cycle. The other options refer at the way in the waves propagates (longitudinal or transversal) and to the type of waveform (sinusoidal), so the right answer is c).2)
At any wave that propagates at a constant speed, there exists a fixed relationship between the velocity v, the frequency f and the wavelength λ, as follows:[tex]v = \lambda * f (1)[/tex]
So in order to v keep constant, if the frequency is increased, the wavelength will decrease in the same proportion, so a) is the right answer.Determine the speed of sound on a cold winter day (Temperature = 3ºC). *
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Answer:
Temperature and Speed of Sound
Temperature of AirSpeed of Sound Waves (m/s)0 °C33120 °C343100 °C386
Explanation:
Write a conclusion to this lab in which you discuss when a person on a roller coaster ride would have sensations of weightlessness and when they would have sensations of weightiness. In your discussion, talk about accelerations and forces. Then finish off your conclusion by using Newton's second law to explain why such accelerations and force conditions cause these sensations.
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Answer:
he lower part of the curve N = M (g + v² / r)
upper part of the curve N = m (v² /r -g)
Explanation:
In a roller coaster there is a long climb that allows the car to acquire gravitational potential energy, when this energy is converted into kinetic energy, there is a raven, in these curves we have two parts the lower part, where you have a feeling of great weight and another in the upper part where you have a feeling of weightlessness.
These sensations can be explained using Newton's second law, let's apply it to the lower part of the curve
N-W = m a
acceleration is centripetal
a = v² / r
we substitute
N = mg + m v² / r
N = M (g + v² / r)
In this part the apparent weight is increased by the speed of the body squared, it feels like a lot of fart.
In the upper part of the curve the force of gravity continues to act downwards, the normal that is the reaction of the surface also goes downwards, the centripetal acceleration pointing towards the center of the curve has a vertical downward direction
-N -W = -m a
N = ma -W
N = m (v² / r -g)
In this case we see that the normal that gives the sensation decreases, which is why we feel a loss of weight, in the case of v2 / r = g, the request is total and the sensation of weightlessness.
A 50kg mass is sitting on a frictionless surface. An unknown constant force pushes the mass for 2 seconds until the mass reaches a velocity of 3m/s. What was the force acting on the mass?
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Answer:
75N
Explanation:
a = v/t = 3/2
F = ma = 50(3/2) = 75
a jogger runs around a quarter of a full track in 10 seconds what is the period of teh motion around teh track
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40 seconds
Explanation:
a quarter is 1/4 so to go the full thing requires you do it 4 time, and sense it takes 10 seconds to do a 1/4 you'd have to multiply 10 by 4.
An accelerometer has a damping ratio of 0.5 and a natural frequency of 18,000 Hz. It is used to sense the relative displacement of a beam to which it is attached. (a)If an impact to the beam imparts a vibration at 4500 Hz, calculate the dynamic error and phase shift in the accelerometer output. (b)Calculateits resonance frequency.(c)What isthe maximumpossiblemagnitude ratio that the system can achieve
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Answer:
A) i) Dynamic error ≈ 3.1%
ii) phase shift ≈ -12°
B) 79971.89 rad/s
Explanation:
Given data :
Damping ratio = 0.5
natural frequency = 18,000 Hz
a) Calculate the dynamic error and phase shift in accelerometer output at an impart vibration of 4500 Hz
i) Dynamic error
This can be calculated using magnitude ratio formula attached below is the solution
dynamic error ≈ 3.1%
ii) phase shift
This phase shift can be calculated using frequency dependent phase shift formula
phase shift ≈ -12°
B) Determine resonance frequency
Wr = 2[tex]\pi[/tex] ( 18000 [tex]\sqrt{0.5}[/tex] ) = 79971.89 rad/s
C) The maximum magnitude ratio that the system can achieve
What is the speed of a vehicle that travels 50 meters in 5 seconds m/s
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Answer:
10m/s
Explanation:
S=D/T
S=50m/ 5sec (make sure to write correct units, they sometimes mark you on that in physics)
S=10 m/sec (be careful of what the units that they want the answer in, different story if it was m/min
hii guys!! ~ i've comeback again!! could you please help me with an assignment?? i have a couple of i know questions!! thank you for helping me, hehe.
tenise can run the 100 meter dash in 9.77 seconds. what is her speed??
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Answer:
Speed = 10.24 m/s.
Explanation:
Given the following data;
Distance = 100m
Time = 9.77
To find her speed;
Speed can be defined as distance covered per unit time. Speed is a scalar quantity and as such it has magnitude but no direction.
Mathematically, speed is given by the equation;
[tex]Speed = \frac{distance}{time}[/tex]
Substituting into the equation, we have;
[tex]Speed = \frac{100}{9.77}[/tex]
Speed = 10.24 meter per seconds.
In separate experiments, four different particles each start from far away with the same speed and impinge directly on a gold nucleus. The masses and charges of the particles are particle 1: mass m0, charge q0 particle 2: mass 2m0, charge 2q0 particle 3: mass 2m0, charge q0/2 particle 4: mass m0/2, charge 2q0 Rank the particles according to the distance of closest approach to the gold nucleus, from smallest to largest.
A. 1, 2, 3, 4
B. 4, 3, 2,1
C. 3, 1 and 2 tie, then 4
D. 4, 1 and 2 tie, then 1
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Answer:
Potential energy at the beginning: Ui =Qq/R*k ≈ 0 (particles are far apart)
Kinetic energy at the beginning: KEi =[tex]mv^{2}[/tex]/2
Potential energy at the end: Uf =(Qq/r)*k
Kinetic energy at the beginning: KEf = 0
From energy conservation:
r = 2*Qk/[tex]v^{2}[/tex]*q/m
Ranking of the closest approach to the gold nucleous comes from q/m:
- particle 3 has the smallest q/m = 1/4 ⋅q0/m0 and, hence, comes the closest
- particle 4 has the largest q/m = 4⋅q0/m0 and, hence, comes the last in ranking
- particles 1 and 2 have equal q/m=q0/m0 and, hence, come tie in between particles 3 and 4
Explanation:
Potential energy at the beginning: Ui =Qq/R*k ≈ 0 (particles are far apart)
Kinetic energy at the beginning: KEi =[tex]mv^{2}[/tex]/2
Potential energy at the end: Uf =(Qq/r)*k
Kinetic energy at the beginning: KEf = 0
From energy conservation:
r = 2*Qk/[tex]v^{2}[/tex]*q/m
Ranking of the closest approach to the gold nucleous comes from q/m:
- particle 3 has the smallest q/m = 1/4 ⋅q0/m0 and, hence, comes the closest
- particle 4 has the largest q/m = 4⋅q0/m0 and, hence, comes the last in ranking
- particles 1 and 2 have equal q/m=q0/m0 and, hence, come tie in between particles 3 and 4
A car comes to a bridge during a storm and finds the bridge washed out. The driver must get to the other side, so he decides to try leaping it with his car. The side the car is on is 21.3 m above the river, whereas the opposite side is a mere 2.3 m above the river. The river itself is a raging torrent 54.0 m wide. 1. How fast should the car be traveling just as it leaves the cliff in order to just clear the river and land safely on the opposite side? 2. What is the speed of the car just before it lands safely on the other side?
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Answer:
Explanation:
1 ) Let the initial horizontal velocity of car be v .
For vertical displacement
vertical displacement h = 21.3 - 2.3 = 19 m
Time taken to fall by 19 m be t
19 = 1/2 x 9.8 t² ( initial downward velocity is zero )
t = 1.97 s
This is also the time taken to cover horizontal displacement of 54 m which is width of river .
horizontal speed v = 54 / 1.97 m /s
v = 27.41 m /s
2 )
At the time of landing on other side , car will have both vertical and horizontal speed .
vertical speed
v = u + gt
= 0 + 9.8 x 1.97 = 19.31 m /s
horizontal speed will remain same as the initial speed = 27.41 m /s
Resultant speed = √ ( 27.41² + 19.31² )
= √ ( 751.3 + 372.87)
= 33.52 m /s
4. Which of these is exerted by an engine?
(1 Point)
Thrust
Water resistance
Friction
Air resistance
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Air resistance is exerted by an engine
Suppose the particle is placed at the 40V equipotential surface along the line connecting the two central positive and negative charges.
(Hint: The electric field can be obtained using the 40V and 30V potential difference lines.)
1. What is the force on the charged particle if q=80μC? (mN) (m-milli 10-3)
2. What is the force on the charged particle if it is now located at the 0V potential difference line? (mN)
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Answer:
Hello some part of your question is missing below is the missing part
2. What is the force on the charged particle if it is now located at the 0V potential difference line? (mN) (hint: The electric field can be obtained as above using the 0V and -10V equipotential lines.)
answer :
1) 0.8 mN
2) 0.8 mN
Explanation:
Given data:
1) Calculate the force on the charged particle
q = 80 μC , Va = 30v , Vb = 40v, ∝ = 1 m
E = ( Δv ) / ∝
= ( Vb - Va ) / ∝
F = qE
= 80 μC * ( 40 - 30 ) / 1 m
= 800 μC
F = 0.8 mN
2) Calculate the force on the charged particle when it is located at 0V
Va = -10V , Vb = 0V, q = 80 μC, ∝ = 1 m
F = qE
where E = ( 0 - ( -10 ) / 1
F = 80 μC * ( 0 - ( -10 ) / 1
= 800 μC = 0.8 mN
How can you explain the process of reflection based from your experience?
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Answer:
Reflection brings learning to life. Reflective practice helps learners find relevancy and meaning in a lesson and make connections between educational experiences and real life situations. It increases insight, and creates pathways to future learning. Reflection is called by many different names in the education field including processing, reviewing, and debriefing. I personally have moved towards referring to this key ingredient in teaching and group facilitation as reflection or reflective practice.
Explanation:
What is the momentum if the mass is 1.5 kg and the velocity is 4 m/s?
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Answer:
6
Explanation:
momentum = mass * velocity
momentum = 1.5 * 4
momentum = 6
Cameron is standing on the edge of a 60 m high cliff. He horizontally throws a football
with an initial velocity of 10 m/s. How long does it take for the football to hit the
ground?
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Answer:34.6 m/s
Explanation: It is asking how long meaning the answer is in time
unlike punishment, reinforcement ____
A. indicates what not to do
B. promotes discrimination
C. promotes generalization
D. indicate what to do
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Answer:
B...................
Hope this helps
Have a great day/night
Feel free to ask any questions
Suppose you need to design a clipper circuit to clip off the portions of an input voltage that fall above +5 V or below +2 V. Assume that diodes having a constant forward drop of 0.7 V are available. Ideal Zener diodes of any breakdown voltage required are available. Dc voltage sources of any value needed are available.
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Answer:
attached below
Explanation:
The required design for a clipper circuit is attached below
From the attached circuit
It can be seen that the battery voltage needs to be high so that it will be in forward bias considering the assumption that the diodes have a constant forward drop of 0.7 V.
hence 4.3 has to be >2.7
How do spectroscopes help with studying of distance stars?
It measures the distance of faraway stars.
It collects sound waves from distant stars.
It breaks apart lights that comes from stars faraway.
It gives a clear image of the shape of stars.
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Answer:
You take the light from a star, planet or galaxy and pass it through a spectroscope, which is a bit like a prism letting you split the light into its component colours. "It lets you see the chemicals being absorbed or emitted by the light source. From this you can work out all sorts of things," says Watson
HELP PLEASE
(Look at the picture)
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Answer:
what is that?
Explanation:
i dont know what us that sorry
Which statements accurately describe sound waves? Check all that apply.
Sound waves are transverse waves.
Sound waves require a medium to transfer energy.
Sound waves start with a vibration.
Energy from a vibration creates a mechanical wave.
Sound can be heard as soon as an object begins vibrating.
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Answer:
the answers are
b) sound waves require a medium to transfer energy
c) sound waves start with a vibration
d) energy from a vibration creates a mechanical wave
Explanation:
i just did this and got 100%, edge 2021
Following statements are true for sound wave,
Sound waves require a medium to transfer energy.Sound waves start with a vibration.Energy from a vibration creates a mechanical wave.In sound waves,
Energy is transferred through vibration of air particles or particles of a solid through which the sound travels.As sound passes through air (or any fluid medium), the particles of air do not vibrate in a transverse mannerA transverse wave is a wave whose oscillations are perpendicular to the direction of the wave's advance.Learn more:
https://brainly.com/question/13105733
Linear Motion is the most basic type of motion. Question 2 options: True False
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Two identical conducting spheres, fixed in place, attract each other with an electrostatic force of 0.152 N when their center-to-center separation is 60.9 cm. The spheres are then connected by a thin conducting wire. When the wire is removed, the spheres repel each other with an electrostatic force of 0.0395 N. Of the initial charges on the spheres, with a positive net charge, what was (a) the negative charge on one of them and (b) the positive charge on the other
Answers
Answer:
a) lets take the positive charge to be
q1 = 3.13 * 10^-6 C
b) lets take the negative charge to be
q2 = 3.13 * 10^-6 C
Explanation:
Given data:
electrostatic force between Two identical conducting spheres = 0.152 N
Center-to-center separation = 60.9 cm = 60.9 * 10^-2 m
When wire is removed
electrostatic force between the spheres ( repelling force ) = 0.0395 N
Determine the negative and positive charges on the identical spheres
q1, q2 = 6.26 * 10^-12 C ( positive net charge )
lets take the positive charge to be
q1 = 3.13 * 10^-6 C
lets take the negative charge to be
q2 = 3.13 * 10^-6 C
since q1,q2 = 6.26 * 10^-12 C
attached below is detailed solution
As you change the value of the battery voltage, how does this change the current through the circuit and the resistance of the resistor
Answers
Answer:
Current increases
Resistance remains same
Explanation:
As you change the value of the battery voltage
We know that the current is dependent on the supply of power , so the current increases but the resistance remains same.
a. What is an electric field line?
b. What are equipotential sufaces are they necessarily physical surffaces?
c. Are they necessarily physical surfaces?
Answers
Answer:
Please see below as the answers are self-explanatory
Explanation:
a)
A electric field line is an imaginary line, which has the property that the electric field vector is tangent to it at any point. It starts from positive charges (since the electric field by convention it has the direction of the trajectory that would take a positive test charge, so it always goes away from positive charges) and ends in negative charges.b)
Since the potential difference between two points represents the work per unit charge needed for a charge to move between these points, a equipotential surface is the one over which it is not needed to do work to move a charge from any point on the surface to any other point, which means that all points are at the same potential.c)
Equipotential surfaces are not necessarily physical surfaces, they can be defined in vaccum for instance.As an example, any spherical surface concentric with a point charge, is an equipotential surface, and it can be a real surface or a fictitious one.During the nineteenth century, biologists knew that South America and Africa contained similar fossils. These fossils let them to believe that a temporary land bridge between South America and Africa allowed ancient species to move between both continents. In the twentieth century, evidence showed that South America and Africa were once part of the same larger continent and that there were no land bridges between them. How should biologists respond to the new geological finding?
A. Biologists should reject the geological finding, because it is new.
B. Biologists should ask physicists what to do, because physics is a more exact science.
C. Biologists should reject the belief in ancient species, because there were no land bridges.
D. Biologists should update the history of life, because it should include the new geological finding.
Explain
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Three adjacent keys on a piano (F, F-sharp, and G) are struck simultaneously, producing frequencies of 349, 370, and 392 Hz. What beat frequencies are produced by this discordant combination?
Answers
Answer:
21 Hz, 43 Hz and 22 Hz
Explanation:
The computation of the beat frequencies that are generated by this discordant combination is as follows:
As we know that
beat frequencies = |f_1 - f_2|
So
For the first one
= |349 Hz - 370 Hz|
= 21 Hz
For the second one
= |349 Hz - 392 Hz|
= 43 Hz
And, for the third one
= |370 Hz - 392 Hz|
= 22 Hz
Question 2 (1 point)
70 cm are equivalent to how many m? State your answer using Scientific Notation.
70 x 10^-2 m
b
7.5 x 10^-2 m
이
ОООО
с
.75 X 10^-2 m
d
0.75 x10^-2 m
uction
Answers
Answer:
A) 70 x 10^-2
Explanation:
it would be 70 times negative 100 which equals 0.70
A substance of mass 200g measures 50cm*4cm*8cm. Calculate it density giving your answer in SI unit
Answers
Answer:
0.2kg/0.0016m^3
Explanation:
200g is 0.2 kg
50*4*8 is equivalent to 1600 cubic centimeters which is also equivalent to 0.0016 cubic meters.
The SI unit for density is kg per cubic meter
So now we have 0.2kg/0.0016m^3
I hoped this helped, and if it did please give me brainliest
I have a problem in this questions?
Answers
Answer:
8.46E+1
Explanation:
From the question given above, the following data were obtained:
Charge 1 (q₁) = 39 C
Charge 2 (q₂) = –53 C
Force (F) of attraction = 26×10⁸ N
Electrical constant K) = 9×10⁹ Nm²/C²
Distance apart (r) =?
The distance between the two charges can be obtained as follow:
F = Kq₁q₂ / r²
26×10⁸ = 9×10⁹ × 39 × 53 / r²
26×10⁸ = 1.8603×10¹³ / r²
Cross multiply
26×10⁸ × r² = 1.8603×10¹³
Divide both side by 26×10⁸
r² = 1.8603×10¹³ / 26×10⁸
r² = 7155
Take the square root of both side
r = √7155
r = 84.6 m
r = 8.46E+1 m