Answer:
25 electrons.
Explanation:
In a neutral atom, the number of protons is equal to the number of electrons, therefore there are 25 protons and 25 electrons.
Final Answer: 25 electrons
Explanation/Reasoning:
Hey there!
The number of protons in the nucleus of a neutral atom would have 25 protons. This is because it is equal to the atomic number.
The number of protons is equal to the number of electrons. So for our answer, the number of atoms in a neutral atom will be 25 electrons because the neutral atom had 25 protons.
~I hope I helped you :)~
A block with a mass of 0.30 kg is attached to a horizontal spring. The block is pulled back from its equilibrium position until the spring exerts a force of 1.2 N on the block. When the block is released, it oscillates with a frequency of 1.1 Hz.
How far was the block pulled back before being released?
Answer:
The value is [tex]x = 0.084 \ m[/tex]
Explanation:
From the question we are told that
The mass of the block is [tex]m = 0.30 \ kg[/tex]
The force exerted is [tex]F = 1.2 \ N[/tex]
The frequency is [tex]f = 1.1 \ Hz[/tex]
Generally the spring constant of the spring is mathematically represented as
[tex]k = (2 \pi f)^2 * m[/tex]
=> [tex]k = (2 * 3.142 * 1.1 )^2 * 0.30[/tex]
=> [tex]k = 14.33 \ N/m[/tex]
Generally the spring constant is also mathematically represented as
[tex]k = \frac{ F }{x }[/tex]
=> [tex]14.33 = \frac{ 1.2 }{x }[/tex]
=> [tex]x = 0.084 \ m[/tex]
A solid disk rotates in the horizontal plane at an angular velocity of 0.649 rpm with respect to an axis perpendicular to the disk at its center. The moment of inertia of the disk is 0.101 kg m2. From above, sand is dropped straight down onto this rotating disk, so that a thin uniform ring of sand is formed at a distance of 0.415 m from the axis. The sand in the ring has a mass of 0.499 kg. After all the sand is in place, what is the angular velocity of the disk
Answer:
The angular velocity of the disk is 0.0369 rad/sec.
Explanation:
Convert 0.649 rpm to rad/s
0.649 rpm = 0.649 * (2π/60) = 0.0679rad/sec
From the question,
Summation of final angular momentum equals summation of initial angular momentum
I*w = Io*wo
w = wo (lo/I)
But I = Isand + Io
and Isand = Msand * R²sand
Therefore, w = wo (lo/I) = wo (Io/Msand * R²sand + Io)
Where,
wo = 0.0679rad/sec
Io = 0.101 kg m2
Msand = 0.499 kg
Rsand = 0.415 m
Hence,
w = 0.0679 {0.101/(0.499*(0.415)²+0.101)}
w = 0.0679 (0.101/0.1869)
w = 0.0679*0.544 = 0.0369 rad/sec
The angular velocity of the disk is 0.0369 rad/sec.
A ray moving in water at 55.5 deg
enters plastic, where it bends to
48.7 deg. What is the index of
refraction for the plastic?
( water n = 1.33, Air n = 1.00 )
Answer:
Refractive index of the plastic = 1.46
Explanation:
By Snell's law,
[tex]\frac{\text{sin}\theta _{2} }{\text{sin}\theta _{1}}=\frac{n_1}{n_2}[/tex]
Here, [tex]\theta _1[/tex] = Angle of incidence in medium 1 (Plastic)
[tex]\theta_2[/tex] = Angle of refraction in medium 2 (Water)
[tex]n_1[/tex] = Refractive index of medium 1 (Plastic)
[tex]n_2[/tex] = Refractive index of medium 2 (Water)
By substituting values in the formula,
[tex]\frac{\text{sin}(48.7)}{\text{sin}(55.5)}=\frac{1.33}{n_2}[/tex]
[tex]n_2=\frac{1.33\times \text{sin}(55.5)}{\text{sin}(48.7)}[/tex]
= 1.46
Therefore, refractive index of the plastic = 1.46
2/3
If the crate has a mass of 80 kg, how much would it weigh?
the surface of objects in contact are not completely smooth true or false
Answer:
true objects in contact are not completely smooth
Need help ASAP plz and thank you!!
Answer: Possibly b
Explanation:
Translatory motion and Circular motion difference between
Correct question is;
What is the difference between Translatory motion and Circular motion.
Answer:
Outlined below
Explanation:
Circular motion is the motion whereby all the particles of a body move along the circumference of a circle while Translatory motion is one in which all particles move in a straight line or a curved fixed part.
Another difference is that in circular motion, the distance moved by all particles vary based on the distance moved from the centre of the circle while in Translatory motion, the distance covered by all particles is equal.
How does solar energy impact the environment? Use in your own words.
1. A 3.8 kg scooter moves with a constant acceleration of 2.5 m/s”. Determine the net
applied force responsible for the acceleration.
Answer:
9.5 NExplanation:
The force acting on an object given it's mass and acceleration can be found by using the formula
force = mass × acceleration
From the question we have
force = 3.8 × 2.5
We have the final answer as
9.5 NHope this helps you
What is the slope of the line that passes through the points (-8, -3)(−8,−3) and (-12, -3) ?(−12,−3)? Write your answer in the simplest form.
single black dude
Notice that both of those points are 3 units below the x-axis. So the line is horizontal ... its slope is zero.
In a physics lab experiment for the determination of moment of inertia, a team weighs an object and finds a mass of 4.67 kg. They then hang the object on a pivot located 0.180 m from the object's center of mass and set it swinging at a small amplitude. As two of the team members carefully count 129 cycles of oscillation, the third member measures a duration of 249 s. What is the moment of inertia of the object with respect to its center of mass about an axis parallel to the pivot axis
Answer:
The value is [tex]I_o = 0.6257 \ kgm^2[/tex]
Explanation:
From the question we are told that
The mass of the object is [tex]m = 4.67 \ kg[/tex]
The position of the pivot from the center of the mass is [tex]a = 0.180 \ m[/tex]
The number of cycles of oscillation is [tex]n = 129 \ cycles[/tex]
The time taken for the total oscillation is t =249 s
Generally the period of the oscillation is mathematically represented as
[tex]T = \frac{t}{n}[/tex]
=> [tex]T = \frac{249}{129}[/tex]
=> [tex]T = 1.9302 \ s[/tex]
Generally the moment of inertia of the object about the end of the suspension is mathematically represented as
[tex]I =[ \frac{T}{2 \pi } ]^2 * [m* g * l ][/tex]
=> [tex]I =[ \frac{1.9302}{2 *3.142 } ]^2 * [4.67* 9.8 * 0.180 ][/tex]
=> [tex]I = 0.777 \ kg m^2[/tex]
Generally the moment of inertia of the object with respect to its center of mass about an axis parallel to the pivot axis is mathematically evaluated using the parallel axis theorem as
=> [tex]I_o = I- I_p[/tex]
Here [tex]I_p[/tex] is parallel axis contribution which is mathematically represented as
[tex]I_p = m * l^2[/tex]
=> [tex]I_p = 4.67 * 0.180^2[/tex]
=> [tex]I_p = 0.1513 \ kg m^2[/tex]
So
[tex]I_o = I- I_p[/tex]
=> [tex]I_o = 0.777 -0.1513[/tex]
=> [tex]I_o = 0.6257 \ kgm^2[/tex]
1. express the following in proper SI form using the appropriate prefixes. a. 52500000 m b. 1000 g c. 2435200000
Answer:
a
[tex]L = 5.25*10^{7} \ m[/tex]
b
[tex]m = 1 \ kg[/tex]
c
[tex]t = 1.46112000000 *10^{11} \ s[/tex]
Explanation:
From the question we are told that
Length is L = 52500000 m
Mass is
Time is 2435200000 minutes
Generally the proper SI for length is meters ,
Now converting the given length to proper SI form using the appropriate prefixes we have that
[tex]L = 5.25*10^{7} \ m[/tex]
Generally the proper SI for mass is kilograms
converting grams to kilograms , we have
[tex]m =\frac{1000}{1000 }[/tex]
=> [tex]m = 1 \ kg[/tex]
Generally the proper SI for time is seconds
converting minutes to seconds , we have
[tex]t = 24352000000* 60[/tex]
=> [tex]t = 146112000000 \ s[/tex]
Now converting to the proper SI form using the appropriate prefixes
[tex]t = 1.46112000000 *10^{11} \ s[/tex]
100 points!! word bank!
⬇️Article⬇️
Have you ever cut an apple in half and looked at the layers inside? When you cut something in half, the resulting view is called a cross section. When you look at the cross section of an apple, you see several layers: the skin, the pulp, the core, and the seeds. Much like the apple, Earth is made up of layers, too. If you could look at a cross section of our planet, you would see the crust. the mantle, the outer core, and the inner core. If Earth were an apple, the crust would be the apple’s skin. The mantle would be the apple’s pulp, making up most of the inside. Earth also has a central core, similar to an apple’s core, though Earth’s core does not contain any seeds! Of course, scientists cannot cut the whole planet in half to see a cross section the way you can with an apple. How do you think scientists know about Earth’s internal layers?
Scientists divide Earth’s interior into distinct layers.
Scientists can distinguish different layers in Earth depending on the properties used to identify each layer. For example, scientists identify the crust, mantle, and core based on each layer’s basic chemical composition. In other words, the crust, mantle, and core are each made up of different chemical elements. The crust and mantle are composed primarily of the elements oxygen and silicon. These are known as silicates. Silicates of the mantle contain heavier elements. This makes them denser than those found in the crust. The core is composed of the densest materials, primarily iron and nickel. Earth’s layers can also be identified by using each layer’s physical state of matter. The crust and the uppermost part of the mantle, together, make up a layer called the lithosphere. The lithosphere is the cool, rigid, outermost layer of Earth. The lithosphere is in the solid
In a typical silicate molecule, a silicon atom is bonded to four oxygen atoms. The atoms form a crystal structure.
Scientists use models to represent the different layers of Earth’s interior.
When constructing a model of the layers of Earth, scientists need to consider the chemical composition, state of matter, and thickness of each layer. Just like the skin of an apple, Earth’s crust is very thin compared to the other layers. It is about 25–70 km thick beneath the continents. Under the oceans, the crust is only about 5–7 km thick; however, it is much denser. The mantle is much thicker than the crust is, taking up most of Earth’s volume. The mantle begins directly beneath Earth’s crust. It reaches all the way to the outer core, about 2,900 km below the planet’s surface. In other words, Earth is about 1% crust, 83% mantle, and 16% core.
The crust and uppermost mantle are solid. The rest of the mantle is solid with plasticity. The core is made of very dense iron and nickel. The outer core is liquid, because it is hot enough to melt the iron and nickel. The inner core is solid. Even though it is as hot as the outer core, there is so much pressure at the very center of Earth that the iron and nickel stay in a solid state.
Looking to the Future: Exploring Earth’s Interior
Despite what you may have read in stories or seen in movies, scientists have never journeyed to the center of Earth. In fact, scientists have never made it through Earth’s crust! However, this has not stopped them from trying. The crust at the bottom of the oceans is much thinner than the crust of the continents. Therefore, drilling through the oceanic crust is the best chance that scientists have to make it to the mantle.
Answer:
Except in the crust, the interior of the Earth cannot be studied by drilling holes to take samples. Instead, scientists map the interior by watching how seismic waves from earthquakes are bent, reflected, sped up, or delayed by the various layers.
Explanation:
An axe used to split wood is driven into a piece of wood for an input distance of 0.05m. If the mechanical
advantage of the axe is 0.85, how far apart (output distance) is the wood split?
Why when i take "The FitnessGram Pacer Test is a multistage aerobic capacity test that progressively gets more difficult as it continues. The 20 meter pacer test will begin in 30 seconds. Line up at the start. The running speed starts slowly, but gets faster each minute after you hear this signal. A single lap should be completed each time you hear this sound. Remember to run in a straight line, and run as long as possible." i don't fall flat on my face?
Answer:
NOOOOOOO NOT THE PACER TEST!!
Explanation:
MEMORIES OF MIDDLE SCHOOL I'D LIKE TO FORGET
also. LOL "Remember to run in a straight line" BRUH WE KNOW XDXD
Explain
applications
MRI
X-ray
Ultrasound
Infrared Radiation
Answer and Explanation:
--> MRI (Magnetic Resonance Imaging) is an imaging technique that involves the use of radio waves and magnetic field to generate high detailed images of the human body. It's clinical applications includes:
• Bone and joint MRI: these are done to check for bone and joint problems such as bone marrow disorders, arthritis, or bone tumours.
• A Spine MRI: This is used to investigate the spinal disc and innervations for disorders such as spinal tumours.
• Chest MRI: This is used to detect abnormalities of the heart, heart valves and coronary arteries.
--> X-RAY: These are electromagnetic waves of short wavelength with high penetrating power. They are produced when fast moving electrons strike a mass of heavy atoms such as those of metals. It's applications includes:
• They are used to detect hidden cracks in materials.
• They are used to show broken bones in human body.
• They are used in the study of internal structures of crystals.
• In agriculture, x-rays are used in killing germs.
--> ULTRASOUND: This makes use of high frequency sounds to detect abnormalities in the human body. An ultrasound machine transmits sound waves into the body which are reflected at the surfaces between the tissues of different density. It can also be used in different disciplines such as imaging, cleaning, mixing, navigation and communication It's applications includes:
•. Detection of Cracks: when applied on metallic surface under investigation, high frequency sound wave reflects back which and be predicted and recorded.
--> INFRARED RADIATION: This is a type of electromagnetic radiation with wavelength longer than visible light. It is visible to the human eye and most heated surfaces transmits infrared radiation. It's applications includes:
• it is used for the purpose of sensing and detection. For example the night vision goggles and infrared cameras. Remote control makes use of infrared light waves to change channels in the television.
A fruit bat falls from the roof of a cave. We know that her potential energy was
600 J, and that the roof of the cave was 12.8 meters high. What is her velocity
when she hits the ground?
Answer:
v = 15.65 m/s
Explanation:
We use conservation of mechanical energy between initial (i) and final (f) states:
Pi + KEi = Pf + KEf
At the top of the cave at the instant the bat starts to fall, there is only potential energy since the bat's velocity is zero.
Pi = m g h = 600 J
and the KEi = 0 J (no velocity)
Knowing the height of the cave's roof (12.8 m) , we can find the mass of the bat:
m = 600 J / (g 12.5) = 4.9 kg
Using conservation of mechanical energy, the final state is:
Pf + KEf = 600 J
with Pf = 0 (just touching the ground)
KEf= 1/2 4.9 (v^2)
and we solve for the velocity:
600 J = 0 + 1/2 4.9 (v^2)
v^2 = 600 * 2 / 4.9 = 244.9
v = 15.65 m/s
you are driving at 18m/s down Lyndale avenue. A car backs out a driveway 25 meters in front of you. You continue at that speed while your brain processes the danger which takes 0.25 seconds. You then slam on the brakes and your car has an acceleration of -5.4m/s^2. Do you stop before reaching the driveway(and hitting the car)? Show your work. This is a two-part problem with constant speed and braking.
Hello!
For this, first let's calculate time of stop:
t = (V - Vi) / a
Replacing:
t = (0 m/s - 18 m/s) / -5,4 m/s^2
Resolving:
t = -18 m/s / -5,4 m/s^2
t = 3,33 s + 0,25 s = 3,58 s
Now lets calculate distance traveled, with formula:
d = Vi*t + (a*t^2)/2
Replacing:
d = 18 m/s * 3,58 s + (-5,4 m/s^2 * (3,58 s)^2) /2
Resolving:
d = 64,44 m + (-34,604 m)
d = 29,83 m
Then, the vehicle will CRASH
A ball weighing 60 N is swinging like a pendulum at the end of a 6.0 m rope. As the ball swings through its lowest point, its speed is measured at 5.0 m/s. What is the tension in the rope at this point?
A. 58.6 N
B. 85.4 N
C. 90.2 N
D. 97.3 N
Answer:
B. 85.4 N
Explanation:
The tension in the rope at the lowest point of the motion of the ball is antiparallel to the weight of the ball. By Newton's laws we construct the following equation of equilibrium:
[tex]\Sigma F = T - W = \left(\frac{W}{g} \right)\cdot \frac{v^{2}}{L}[/tex] (1)
Where:
[tex]T[/tex] - Tension in the rope, measured in newtons.
[tex]W[/tex] - Weight, measured in newtons.
[tex]g[/tex] - Gravitational acceleration, measured in meters per square second.
[tex]v[/tex] - Speed of the ball, measured in meters per second.
[tex]L[/tex] - Length of the rope, measured in meters.
If we know that [tex]W = 60\,N[/tex], [tex]g = 9.807\,\frac{m}{s^{2}}[/tex], [tex]v = 5\,\frac{m}{s}[/tex] and [tex]L = 6\,m[/tex], then the tension in the rope at this point is:
[tex]T = W+\frac{W\cdot v^{2}}{g\cdot L}[/tex]
[tex]T = W\cdot \left(1+\frac{v^{2}}{g\cdot L} \right)[/tex]
[tex]T = (60\,N)\cdot \left[1+\frac{\left(5\,\frac{m}{s} \right)^{2}}{\left(9.807\,\frac{m}{s^{2}} \right)\cdot (6\,m)} \right][/tex]
[tex]T = 85.492\,N[/tex]
Hence, the correct answer is B.
Use the following information to answer questions 6 and 7:
A61.0 kg grocery cart is sitting at rest. In order to change the cart's state of motion, Xavier must apply 72.1
Newtons of force on the cart.
6. How much magnitude of force does the cart exert back on Xavier's hand?
A. 4400 N
B. 1.20 N
C. 72.1 N
D. 0.00 N
After 10 seconds, the dirt has achieved a velocity of +3.62 m/s. Xavier is still applying 72.1 Not force on the
cart.
7. Xavier's sister Maria claims that the cart is in dynamic equilibrium. Is Maria correct?
A Maria is correct because the cart is traveling at a constant velocity while experiencing balanced
forces.
B. Maria is correct because the cart's velocity has changed.
C. Maria is incorrect because the cart is traveling at a constant velocity while experiencing
unbalanced forces.
D. Maria is incorrect because the cart's velocity has changed
Question 6
C. 72.1 N
Its simply the newton Third law, whenever two objects interact, they exert equal and opposite forces on each other.
Question 7
D. Maria is incorrect because the cart's velocity has changed
The car is accelerating so, It is not in dynamic equilibrium. Remember that by the Newton Second Law:
F = ma
The cart is in dynamic equilibrium. The correct options for the two question are:
6. C
7. A
6.) Given that a 61.0 kg grocery cart is sitting at rest. And Xavier applied 72.1 Newtons of force on the cart.
According to Newton's third law of motion which state that, in every action, there will be equal and opposite reaction. The magnitude of force That the cart exert back on Xavier's hand will be opposite and equal to the force applied. which is negative 72.1 N
7.) If the grocery cart is moving in a constant velocity, then it will achieve a dynamic equilibrium. In this scenario, the air resistance force balances with the applied force.
Therefore, Maria is correct because the cart is traveling at a constant velocity while experiencing balanced forces.
Learn more about equilibrium of forces here: https://brainly.com/question/9076091
A car of mass 1150 kg drives in a circle of radius 44 m. If the car has a speed of 13 m/s, what is the
centripetal force acting on the car?
Answer:
4417
i think because
mv^2/r is centripetal force
two spheres A and B are projected off the edge of a 1.0 m high table with the same horizontal velocity . sphere A has a mass of 20.g and sphere B has a mass of 10.g.
If both spheres leave the edge of the table at the same instant, sphere A will land
a. at some time after sphere B.
b. at the same time as sphere B.
c. at some time before sphere B.
d. There is not enough information to decide.
__ 6. If both spheres leave the edge of the table at the same instant, sphere A hits the floor at the spot marked X. Sphere B will hit the floor
a. at some point between the edge of the table and X.
b. at some point past X.
c. at the same distance from the table as X.
d. there is not enough information to decide.
Answer:
C. and D.
C. becuase A is heavier so it will land first
.
Calculate the potential energy of a 6 kg bowling ball suspended 3 m above the surface of the Earth.
Answer: 176.4 J
Explanation:
What energy transformation takes place in the
solar panel?
Question 10 of 10
In the photoelectric effect, an electric current forms when light strikes a metal
surface. Which statement explains what causes the current?
O A. Electrons flow from one atom to another because the light acts as
a wave.
O B. The light causes electrons to flow in different directions within an
atom because light acts as a wave.
O C. Electrons are destroyed when light strikes a surface because the
light acts as particles.
D. Electrons are knocked off the surface when light strikes it because
the light acts as particles.
Explanation:
D. I hope i helped it should be right but if it isn't my bad
In the photoelectric effect, an electric current forms when light strikes a metal surface because electrons are knocked off the surface when light strikes it because the light acts as particles, The correct option is D.
What is the photoelectric effect?
It is the process of emission of electrons from the material because of absorption of electromagnetic radiation in form of photons of light waves.
The photoelectric effect explains the particle behavior of the light waves.
The photoelectric effect is responsible when electrons are knocked off the surface when light strikes it because the light acts as particles.
Learn more about the photoelectric effect
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A bowling ball weighing 71.2 N is swinging like a pendulum at the end of a 3.8 m rope. As the ball swings through its lowest point, its speed is measured at 4.2 m/s. What is the magnitude and direction of the acceleration of the ball at this point?
At its lowest point, the ball feels a downward force due to its weight of 71.2 N and an upward force of tension from the rope. Its motion is circular, so that the net radial acceleration is felt upward toward the center of the circle.
With a tangential speed of 4.2 m/s at the lowest point, its radial acceleration has magnitude
a = (4.2 m/s)² / (3.8 m) ≈ 4.6 m/s²
Can you help with this question please
Answer:
First answer to the first question is Two people pulling a rope with the same force in a opposite direction. The other one would be 2.72N
Explanation:
Hope this helps you :)
The skateboarder weighs 75 kilogram. Calculate the potential energy of the skateboarder sliding on the track when his height above the ground is 5 meters. (Assume that acceleration due to gravity is 9.81m/s2.)
Answer:F(of gravity) = MA
F(normal force) = MA * cos(angle)
F = 72 * 9.81 * cos28
Don't have a calculator, so can't really do all the math right there. So just plug that in
Explanation:
i dont really know
Potential energy of a body is the product of its mass, height and acceleration due to gravity. The potential energy of 75 Kg skateboard sitting at 5 meter high is 3675 J.
What is potential energy?
Potential energy of a body is generated by virtue of the position of the body. It is dependent on the mass of the body and the height at which it is placed and the acceleration due to gravity.
Whereas kinetic energy of an object is a form of energy generated by virtue of the motion of the object. Kinetic energy is dependent on the mass and velocity of the body.
It is given that the mass of the object is 75 Kg and the height from the surface is 5 m. Acceleration due to gravity on earth is 9.8 m/s².Thus, the potential energy is calculated as follows:
p = m g h
= 75 Kg × 9.8 m/s² × 5 m
= 3675 J.
Therefore, the potential energy of the skateboard is 3675 J.
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Which is an example of a chemical change?
frying an egg
boiling water
melting butter
chopping onions
Answer:
Frying an Egg
Explanation:
When chemical bonds are broken or formed, new particles are created. Therefore, frying an egg is a chemical change because it results in the formation of new particles.
Frying an egg is an example of chemical change. Therefore, option (A) is correct.
What is the chemical change?A chemical change can be described as a change in which a chemical substance is converted into one or more new types of substances. Chemical changes occur through chemical reactions that result in substances with different properties.
Chemical changes are irreversible in nature and are also called permanent changes in which an entirely new substance is formed. We have three kinds of chemical change organic, biochemical and inorganic.
While frying an egg, the egg changes from a fluid to a strong one. The egg changes from a fluid protein into a strong mass. Actually, the strands of protein extend, permitting the protein to denature by breaking the chemical bonds and formation of a new product.
Therefore, Frying an egg is a chemical change while boiling water, melting butter, and chopping onions are physical changes.
Learn more about chemical change, here:
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A 60-W light bulb radiates electromagnetic waves uniformly in all directions. At a distance of 1.0 mfrom the bulb, the light intensity is I0, the average energy density of the waves is u0, and the rms electric and magnetic field values are E0 and B0, respectively.
At 2.0 m from the bulb, what is the light intensity?
Answer:
I0/4
Explanation:
If the difference is increasedby a factor of two(i.e twice it's original value), then the light intensity happens to get reduced by one-fourth. This means that the light intensity would be:
I0/4