Answer:
A
Explanation:
i just took the test
Answer:
A - Fusion !
Explanation:
Person above me is correct, I just took "The Impact of Human Activity" Unit Test.
Define resistance of a conductor. State the factors on which resistance of a conductor depends.
Name the device which is often used to change the resistance without changing the voltage source in an electric circuit.
Calculate the resistance of 50 m length of wire of cross-sectional area 0.01 square mm and of resistivity 5 ×10 ^-8 ohm m
1. Resistance is the opposition offered in a path of flow of current by the atoms or molecules of the conductor.
Factors on which resistance of a conductor depends are:
Length [tex]R \propto l[/tex]Area of cross section [tex]R \propto \dfrac{1}{A}[/tex]Nature of the material2. Rheostat is used to change the resistance without changing the voltage source in an electric circuit.
3.
Given :
[tex]\dashrightarrow l = 50 m[/tex]
[tex]\dashrightarrow A = 0.01 {mm}^{2} [/tex]
[tex]\dashrightarrow A = 0.01 \times {10}^{ - 6} \: {m}^{2} [/tex]
[tex]\dashrightarrow \rho = 5 \times {10}^{ - 8} \: \Omega \: m[/tex]
We know that,
[tex] \dashrightarrow R = \rho \dfrac{l}{A}[/tex]
[tex] \dashrightarrow R = 5 \times {10}^{ - 8} \bigg(\dfrac{50}{0.01 \times {10}^{ - 6} } \bigg)[/tex]
[tex] \dashrightarrow { \pink{ \underline{ R = 250 \: \Omega }}}[/tex]
The resistance of a conductor is the opposition to the flow of current and depends on the length and area of the material
What is resistance of a conductor?Resistance is the opposition to the flow of current by the atoms or molecules of the conductor.
The factors on which resistance of a conductor depends are:
Length of materialcross-sectional area of the materialNature of the materialA Rheostat is the device used to change the resistance without changing the voltage source in an electric circuit.
The resistanceis given as:
R = resistivity × length/ areaArea = 0.01 square mm = 1.0 × 10^-8 square m
R = (50 × 5 ×10 ^-8 ohm m)/1.0 × 10^-8 square m
Resistance = 250 ohm
Therefore, resistance of a conductor is the opposition to the flow of current.
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If a fast-moving car making a loud noise approaches and moves past a person, which of the following will happen as the distance between the two increases?
A) The pitch and frequency of the sound waves reaching the person's ear will remain unchanged.
B) The pitch of the sound being heard by the person will appear to be lower than the pitch of the source.
C) The frequency of the sound waves reaching the person's ear will be greater than the frequency of the waves leaving the car.
D) The pitch of the sound being heard by the person will appear to be higher than the pitch of the source.
Answer:
(B) Probably - Pitch will appear to be lower than the source
Pitch differences occur because of relative motions between the source and observer - it does not depend on distance measurements
Answer:
(B) Probably - Pitch will appear to be lower than the source
Pitch differences occur because of relative motions between the source and observer - it does not depend on distance measurements
Explanation:
If you travel for three hours at a speed of 30 km/h, how far will you go?
Distance = (speed) x (time) <== This is important. You should memorize it.
Distance = (30 km/hr) x (3 hr)
Distance = (30 x 3) (km/hr x hr)
Distance = 90 km
100 Points!!!
1.) What does the image of an object look like through a convex lens when the object is further from the lens than the focal point?
A. It looks the same as the actual object.
B. It is right side up and larger than the object.
C. It is upside down and larger than the object.
D. It is upside down and smaller than the object.
2.) What happens when light rays reflect?
A. They are partially absorbed.
B. They bounce back.
C. They are all absorbed
D. They pass through an object.
3.) Based on how it refracts light, what would you expect images formed by a concave lens to look like?
A. Smaller
B. The same as the objects that they are images of
C. Magnified
D. Reversed
4.) What happens to light rays when they enter a different medium?
A. They reflect
B. They Bend
C. They Curve
D. They Stop
(1) The image of an object placed further from the lens than the focal point will be upside down and smaller than the object.
(2) When light rays reflect, they bounce back.
(3) Images formed by a concave lens will look magnified.
(4) When light rays enter a different medium, they bend.
1.0 Object placed further from the lens than the focal pointThe image of an object placed further from the lens than the focal point will be diminished and inverted.
Thus, the correct answer will be "upside down and smaller than the object".
2.0 What is reflection of light?The ability of light to bounce back when it strike a hard surface is known as refection.
3.0 Image formed by concave lensA concave lens is diverging lens is usually virtual, erect and magnified.
4.0 Refraction of lightThe change in speed of light when it travels from medium to another medium is known as refraction. Refraction is also, the ability of light to bend around obstacles.
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Answer:
It is upside down and larger than the object
They bounce back
Magnified
They bend
Explanation:
Use the claim to answer the question.
Claim: Electromagnetic radiation can be described by a wave model or a particle model, depending on the situation.
Is this a scientific claim?
(1 point)
Yes, it can be backed up by experiments and evidence.
No, radiation is invisible, so there is no evidence to back up the claim.
Yes, any statement made by a scientist is a claim.
No, models can't be part of a scientific claim.
Scientific evidence such as reflection and photoelectric effect has proven the wave-particle model of electromagnetic radiation to be true.
What is electromagnet radiation?Electromagnetic radiation is radiation produced as a result of the interactions of the electric and magnetic fields.
Some forms of electromagnetic radiation include:
radio wavesmicrowavesultraviolet radiationvisible lightElectromagnetic radiation can be described using a wave model or a particle model.
The wave property of electromagnetic radiation include:
diffraction reflectionrefractionThe particle property of electromagnetic radiation include:
photoelectric effectCompton effect.Therefore, the wave-particle model of electromagnetic radiation is correct because it can be backed up by experiments and evidence.
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Answer:
I just took the identifying Claims Quick check
Explanation:
1. Claim: Electromagnetic radiation can be described by a wave model or a particle model, depending on the situation.
Is this a scientific claim?
Yes, it can be backed up by experiments and evidence.
2. A student states, "The wave model is better than the particle model for electromagnetic radiation because it is easier to understand." Is the student's statement a scientific claim?
No, it isn't because the statement is an opinion.
3. A student wants to make a scientific explanation regarding the wave model of electromagnetic radiation. Which of the following would be part of the scientific explanation?
Claims
4. A student makes this statement before conducting an experiment on electromagnetic radiation: "We expect the laser to diffract when passed through a slit." Which of the following explains why the student's statement is not a claim?
It is a prediction or hypothesis.
5. Which claim do scientists use to describe electromagnetic radiation?
Electromagnetic radiation exhibits properties of both particles and waves.
6. A physician is going to use high-frequency electromagnetic radiation to treat cancer in a patient. Which is a claim about this event?
A wave model is most useful for describing the frequency of the radiation.
List the elements mentioned from hydrogen to iron in the order of their fusing temperature.
Explanation:
H
Hydrogen
-259.14 -252.87 0.00008988 (gas, 273K)
2
He
Helium
-272.20 (under pressure) -268.934 0.0001785 (gas, 273K)
3
Li
Lithium
180.54 1347 0.534
4
Be
Beryllium
1278 2970 1.8477
5
B
Boron
2300 3658 2.34
6
C
Carbon
3527 4827
(sublimes) 2.260 (graphite)
3.513 (diamond)
7
N
Nitrogen
-209.86 -195.8 0.0012506 (gas, 273K)
8
O
Oxygen
-218.4 -182.96 0.001429 (gas, 273K)
9
F
Fluorine
-219.62 -188.14 0.001696 (gas, 273K)
10
Ne
Neon
-248.67 -246.05 0.00089994 (gas, 273K)
11
Na
Sodium
97.81 882.9 0.971
12
Mg
Magnesium
648.8 1090 1.738
13
Al
Aluminum
660.37 2467 2.698
14
Si
Silicon
1410 2355 2.329
15
P
Phosphorus
44.1 (white)
410 (red, under pressure) 280 (white) 1.82 (white)
16
S
Sulfur
113 (α)
119 (b)
106.8 (g) 444.67 2.070 (α)
1.957 (b)
17
Cl
Chlorine
-100.98 -33.97 0.003214 (gas, 273K)
18
Ar
Argon
-189.37 -185.86 0.001784 (gas, 273K)
19
K
Potassium
63.65 774 0.862
20
Ca
Calcium
839 1484 1.55
21
Sc
Scandium
1541 2831 2.989
22
Ti
Titanium
1660 3287 4.54
23
V
Vanadium
1887 3377 6.11 (292 K)
24
Cr
Chromium
1857 2672 7.19
25
Mn
Manganese
1244 1962 7.44
26
Fe
Iron
1535 2750 7.874
27
Co
Cobalt
1495 2870 8.90
28
Ni
Nickel
1453 2732 8.902 (298 K)
29
Cu
Copper
1083.4 2567 8.96
30
Zn
Zinc
419.58 907 7.133
31
Ga
Gallium
1. A hockey puck has a mass of 0.115-kg and strikes the pole of the net at (37 m/s)x. It bounces off in the opposite direction at (-25 m/s)x +(5 m/s)y. (A) What is the impulse on the puck? (B) If the collision takes .005s what is the force acted on the puck?
(a) The impulse on the puck is 1.323 kgm/s.
(b) The magnitude of the force that acted on the puck is 264.5 N.
Impulse of the puckThe impulse on the puck is equal to the change in momentum of the puck.
The change in th momentum of the puck is calculated as follows;
ΔP = m(u - v)
where;
v is the final velocity = (-25x + 5y) m/su is the initial velocity = 37 m/sMagnitude of the final velocity
|v| = √[(-25)² + (5)²] = 25.5 m/s
ΔP = 0.115(37 - 25.5)
ΔP = 1.323 kgm/s
Thus, the impulse on the puck is 1.323 kgm/s.
Force on the puckThe magnitude of the force that acted on the puck is calculated as follows;
F = ΔP/t
F = 1.323/0.005
F =264.5 N
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A 1500kg car moving at a speed of 20.1m/s comes toa stop after travelling a distance of 200m. What was the average force exerted by the breaks on the car?
Answer:
= -1515N
Explanation:
v^2=u^2+2as
0m/s
u=20.1m/s
0=(20.1)^2+(2xax200)
0=404.01+400a
-404.01=400a
-404.01÷400=a
a= -1.01m/s^s
its negative because the force is slowing down the car
Newton's second law of motion
F=ma
=1500×-1.01
F= -1515N
What increases the transfer of the wind's energy to the water?
Question 4 options:
A. flat water
B. large waves
C. large rocks
PLEAS HELP ME FAST
Answer:
A, flat water
Explanation:
Where are active volcanoes most likely to found?
A.where rivers form
B where tectonic plate meet
C. Where oceans are deepest
D. Where land and water meet
Answer:
B. where tectonic plates meet
Explanation:
Most volcanoes occur near tectonic plate boundaries. For example, a large amount are found on the Ring of Firez connecting several plates.
Hello people ~
what's the value of acceleration due to gravity on earth?
Answer:
9.8 m/s2
Its value is 9.8 m/s2 on Earth. That is to say, the acceleration of gravity on the surface of the earth at sea level is 9.8 m/s2. When discussing the acceleration of gravity, it was mentioned that the value of g is dependent upon location.
Which claim do scientists use to describe electromagnetic radiation?
(1 point)
Electromagnetic radiation exhibits properties of particles only.
Electromagnetic radiation exhibits properties of both particles and waves.
Electromagnetic radiation doesn't exhibit properties of either particles or waves.
Electromagnetic radiation exhibits properties of waves only.
Answer:c
Explanation: I took the identifying claims quick check and the answers are 1.yes it can be 2. No because it is an opinion 3.claims 4.it is prediction 5.both particles and waves 6.a wave model is most useful
Scientists use to describe electromagnetic radiation as It exhibits properties of both particles and waves. The correct option is B.
What is an electromagnetic wave?An electromagnetic wave is a type of wave that consists of oscillating electric and magnetic fields that travel through space at the speed of light.
Electromagnetic waves are produced by the movement of charged particles and are characterized by their frequency, wavelength, and amplitude.
Electromagnetic waves include a wide range of frequencies, which together form the electromagnetic spectrum. The spectrum includes radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, X-rays, and gamma rays. Each of these types of electromagnetic waves has a different frequency and wavelength, which determines its properties and how it interacts with matter.
Here in the question,
Scientists describe electromagnetic radiation as exhibiting properties of both particles and waves.
This is known as the wave-particle duality of electromagnetic radiation, which means that electromagnetic radiation can exhibit both wave-like and particle-like behavior depending on how it is observed or measured.
The wave-like behavior is described by its frequency, wavelength, and amplitude, while the particle-like behavior is described by its energy, momentum, and photons.
Therefore, The electromagnetic wave shows duality i.e both particle and wave properties.
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The objects shown in the following diagrams have different masses and are different distances apart. Which diagram shows the two objects that have the greatest force of gravity acting between them?
Answer:
C. 10kg to 10kg
Explanation:
You have to picture to it I think
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
( Infer this information for both the lens and mirror based on the data collected. Report these ranges in terms of f and/or 2f. For example, “When do is less than 2f.” )
What range of do values will result in a real image?
What range of do values will result in a virtual image?
What range of do values will result in a smaller image?
This exercise is about Reflection and Mirrors. It explores the relationship between convex mirrors, virtual images, and complex images as well as to object distance d₀.
Any d₀ value greater than 10 for a convex lens will produce a true or real image, while any d₀ value greater than 15 for a complex mirror will produce a real image.
What range of d₀ values will result in a virtual image?Any d₀ number less than 10 for a convex lens will result in a virtual image. Also, any d₀ value less than 15 for a complex mirror will result in a virtual picture.
What range of do values will result in a smaller image?The range of d₀ values that would result in a reduced picture in both lenses and mirrors is:
d₀ > 2 f, where is the Focal length.
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Martha wants to calculate an object's velocity. What will she need to do?
Answer:
you divide the distance by the time it takes to travel that same distance, then you add your direction to it.
Mass m1 on the frictionless table of the figure is connected by a string through a hole in the table to a hanging mass m2
For a mass m1 on the frictionless table, the speed m1 must rotate a with radius r if m2 is to remain hanging at rest is mathematically given as
[tex]v=\sqrt{m1/m2*xg}[/tex]
What speed must m1 rotate in a circle of radius r if m2 is to remain hanging at rest?Generally, the equation for the Force is mathematically given as
Fc=Fw
Therefore
[tex]\frac{m1v1}{x}=m2g[/tex]
[tex]v=\sqrt{m1/m2*xg}[/tex]
In conclusion, if m2 is to remain hanging at rest the speed of ratio of m1 is calcuylated using
[tex]v=\sqrt{m1/m2*xg}[/tex]
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The value of the velocity for the mass m₁ on the frictionless table will be [tex]\rm v = \sqrt{\frac{m_1}{m_2 xg} }[/tex]. Velocity is a time-based component. Its unit is m/sec.
What is velocity?The change of distance with respect to time is defined as speed. Speed is a scalar quantity.
The given data in the problem is
m is the mass
g is the acceleration of free fall =10m/sec²
v is the velocity
From the balancing equation of force the centripetal force is equal to the weight;
[tex]\rm F_c= m_2 g \\\\ \rm \frac{m_1v_1^2}{x} = m_2 g \\\\ v= \sqrt{\frac{m_1}{m_2xg} } \\\\[/tex]
Hence the value of the velocity for the mass m₁ on the frictionless table will be [tex]\rm v = \sqrt{\frac{m_1}{m_2 xg} }[/tex].
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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
Matthew drops a cherry pit out the car window 1.0m above the ground while traveling down the road at 18m/s.
a) How far, horizontally, from the initial dropping point, will the pit hit the ground
b) Draw a picture of the situation.
c) If the car continues to travel at the same speed, where will the car be in
relation to the pit when it lands?
Answer:
ADD ALL THEM AND ANSER WILL BE THERE 19.O
Explanatio
Which statement correctly describes the relationship between frequency and wavelength?
A :As the frequency of a wave increases, the longer its wavelength is
B: As the frequency of a wave increases, the shorter its wavelength is.
C: As the frequency of a wave increases, its wavelength remains the same.
Answer:
Answer:
Option B
Explanation:
Option B talks about how the frequency of the wave increases the shorter it's wavelengths
Answer:
b
Explanation
B: As the frequency of a wave increases, the shorter its wavelength is.
4. Which best explains the function of the alveoli in the respiratory system?
Page 135
A. The alveoli help to keep the lungs healthy by providing a way for all the cells
in the lungs to obtain nutrients from the bloodstream
B. The alveoli help to keep the lungs inflated when you breathe out and make it
possible to absorb oxygen
C. The alveoli provide a large surface area for absorbing oxygen from the air and
releasing carbon dioxide wastes from the bloodstream
D. The alveoli provide a large surface area for absorbing oxygen from the air
when you breathe in and look like a bunch of grapes
a
Answer:
C
Explanation:
Alveoli are tiny functioning structures that compose your lungs. They help with respiration. They have a large total surface area, which is very useful for respiration. The more surface area there is, the more transactions can happen. Which means that breathing will be easier/faster when you have more alveoli. (Please rate this answer if you have time!)
How many electrons will it take to give a hot wired fence a charge of 3.5 X 10^6 C?
Answer:
Q = N e where N e is the number of electrons required to produce charge Q
N = Q / e = 3.5E6 C / 1.6E-19C = 2.2E25 = 2.2 X 10^25 electrons
Answer:
3.5 million C
Explanation:
Why does the final electron energy not depend on the focusing cylinder voltage?
The electron energy does not depend on the focusing cylinder voltage because the magnetic field runs perpendicular to the electron's direction of movement.
What is a magnetic field?A magnetic field is produced by moving negatively electric charges (electrons) which generate magnetic forces that are observable.
The negative electrons that orbit around atoms in a molecule generate small magnetic fields around such atoms.
According to Fleming's left-hand rule, the direction of a magnetic force acting on a current is perpendicular to the direction of the electric current and magnetic field.
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Because it exerts a force that's also parallel to the horizontal fields instead of in opposition to it, the final electron energy is unchanged by the focusing cylinder voltage.
What is electron energy?An electron's energy is on the same scale (in the same range) as that of light. The lines in an element's spectrum represent changes in the energy of electrons within the element's atoms. Scientists have reached numerous conclusions regarding the behavior of electrons in atoms by studying these spectra.
Negative electrons orbiting around atoms in a molecule produce modest magnetic fields surrounding them.
The vector of a magnetic force that acts on a current is opposite to the axis of the electric current and magnetic fields, as per Fleming's left-hand rule.
Thus, because it exerts a force that's also parallel to the horizontal fields instead of in opposition to it, the final electron energy is unchanged by the focusing cylinder voltage.
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why did united states withdraw from vietnam war
the Army had a fight in unfamiliar territory but with the combination of disadvantages and a loss of public support what to the United States withdrawing from Vietnam
Explanation:
I hope this helps
A bicycle wheel of radius 40. 0 cm and angular velocity of 10. 0 rad/s starts accelerating at 80. 0 rad/s2. What is the centripetal acceleration of the wheel at this time point?
The magnitude of the centripetal acceleration of the bicycle wheel is 40 m/s².
Centripetal acceleration of the wheel
The centripetal acceleration of the bicycle wheel is the inward or radial acceleration of the bicycle on the circular path.
The magnitude of the centripetal acceleration of the bicycle wheel is calculated as follows;
a = ω²r
where;
ω is angular speed
r is the radius of the circular path
a = (10)² x 0.4
a = 40 m/s²
Thus, the magnitude of the centripetal acceleration of the bicycle wheel is 40 m/s².
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The acceleration of a body travelling in a circular route is known as centripetal acceleration. The centripetal acceleration of the wheel at this time point is 40 m/sec².
What is centripetal acceleration?The acceleration of a body travelling in a circular route is known as centripetal acceleration. It is given by the formula,
[tex]a_c = \dfrac{v^2}{r} = \omega^2 r[/tex]
The centripetal acceleration of the wheel with angular velocity 10 rad/sec and velocity 40cm (0.4 m) can be written as,
[tex]a_c = \omega ^2\times r\\\\a_c = (10)^2\times 0.4\\\\a_c = 40\rm\ m/sec^2[/tex]
Hence, the centripetal acceleration of the wheel at this time point is 40 m/sec².
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Two cities in the same climate zone must have the same climate and weather conditions. Why is this statement true or false?
A. It is false because cities in the same climate zone must have different climates.
B. It is false because the two cities might differ in their proximity to water.
C. It is true because the two cities are at the same latitude.
D. It is true because the two cities will be closer to the equator.
Answer:
C
Explanation:
true because c is the best answer
Answer: The answer is C. It is true because the two cities are at the same latitude.
Explanation:
Hi I was doing the same test are u in flvs lol I am too if you are!
Different Betweens in Current Source And Voltage Source.
[tex] \\ \\ \\ \\ \\ \\ \\ [/tex]
Thanks:')
Answer:
Voltage and current sources are two different sorts of sources that may be found in an electrical network. A voltage source has an emf forcing function, whereas a current source has a current forcing function.
☆ ------ ☆ ------ ☆ ------ ☆ ------ ☆
If all of the resistors in the circuit were decreased in value by a factor of 1,000, would the current in each resistor simply increase by a factor of 1,000? explain your answer
In a circuit, if the resistors were decreased by a factor of 1,000, it is true that the current would increase by a factor of 1,000, according to Ohm's Law.
What is Ohm's Law?It is a law in electricity that posits that the voltage that goes through a conductor is directly proportional to the current.
How does Ohm'slaw explain the change in current?One formula in Ohm's law is:
Voltage = Current x Resistance
If the resistance were to decrease by a factor of 1,000, the current would have to increase by a factor of 1,000 as well in order to give the same voltage.
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A rock with a 8 kg mass is tied to a string and swung in a circular path. The 1.8 meter string is tied to a post, and during the motion, the string has a 35° angle with the post. The rock makes 100 rounds in 3 minute. The centripetal force on the ball is __ N.
The centripetal force of the rock tied to a string and swung in a circular path is determined as 1.65 N.
Angular speed of the rock
The angular speed of the rock is calculated as follows;
ω = 2π N
[tex]\omega = 35^0 \times \frac{2 \pi \ rad}{360^0} \times \frac{100}{3\min} \times \frac{1 \min}{60 \ s} \\\\\omega = 0.339 \ rad/s[/tex]
Centripetal force of the rockThe centripetal force of the rock is calculated from the product of mass and centripetal acceleration as shown below;
Fc = ma
Fc = m(ω²r)
Fc = mω²r
Fc = 8 x (0.339)² x 1.8
Fc = 1.65 N
Thus, the centripetal force of the rock tied to a string and swung in a circular path is determined as 1.65 N.
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Two horses pull horizontally on ropes attached to a tree stump each horse pulls with a force of F if the angle between the two ropes is 126° what's resultant force?
Answer:
126 / 2 = 63 = angle between one rope and the direction of the resultant force
t = F cos 73 = .45 F force on stump due to one horse
T = 2 t = .90 F force on stump due to both horses - T would be the resultant of the two horses each pulling with force F