Answer:
W = 1250 J = 1.25 KJ
Explanation:
The work done by the boy is due to the change in the position of the cement vertically. Hence, the work done in this case will be equal to the potential energy of the cement:
[tex]W = P.E\\W = mgh[/tex]
where,
W = Work done = ?
mg = W = weight of cement = 500 N
h = height covered = 2.5 m
Therefore,
[tex]W = (500\ N)(2.5\ m)[/tex]
W = 1250 J = 1.25 KJ
What should a student do if the hydrochloric acid splashes in their eyes?
.
First aid suggestions include:
Hold your face under running water for 15 to 20 minutes and allow the water stream to flood into your eyes. Use your fingers to hold your eyelids apart (make sure there is no trace of the chemical on your fingers).
If you wear contact lenses, remove them as soon as possible.
Seek immediate medical advice. Medical staff will need to know what chemical was involved, particularly whether it was acid or alkaline, liquid or powder.
Do not judge the seriousness of your eye injury on the degree of pain. For example, alkali chemicals don’t usually cause significant symptoms, but can seriously damage the eye.
Powder or particulate (granular matter, like wet concrete) chemicals can be particularly damaging since they are more difficult to flush out.
Answer:
immediately wash eyes with water
A change in state is considered a
A.
Chemical change
B.
Physical Change
C.
Element
D.
Density
[tex]\huge{ \mathfrak{ \underline{Áñswér: }}}[/tex]
A change in state is considered a :
[tex] \hookrightarrow { \mathbb{\: physical \: change}}[/tex]
[tex]\#TeeNForeveR [/tex]
what is a material used to reduce or prevent the transfer of electricity, heat, or sound ?
Answer:
The material you're looking for is insulation.
Explanation:
It reduces and/or stops electricity waves, heat waves, and sound waves from going past.
this is a test a b c d e f g h i j k l m n o p
Answer:
???????????????????????????????????????
Explanation:
Answer:
q r s t u v w x y z
Explanation:
Think of Rutherford's experiment. Most alpha particles passed straight through, but a few were repelled so strongly that they were bounced back or deflected at large angles. This led Rutherford to conclude that the charge of the nucleus of an atom must be... what?
Answer:
Rutherford considered these observations and he concluded: The fact that most alpha particles went straight through the foil is evidence for the atom being mostly empty space. A small number of alpha particles being deflected at large angles suggested that there is a concentration of positive charge in the atom.
Hope it helps
Most alpha particles passed straight through, but a few were repelled so strongly that they were bounced back or deflected at large angles. This led Rutherford to conclude that the charge of the nucleus of an atom must be positive.
What are atomic models?There are some models that are used to explain the arrangements of subatomic particles inside the atom based on the atomic theory of atoms known as the atomic models.
As given in the problem statement Think of Rutherford's experiment. Most alpha particles passed straight through, but a few were repelled so strongly that they were bounced back or deflected at large angles.
Most alpha particles were resisted so strongly that they were bounced back or deflected at huge angles, but a handful did not.
Hence, Rutherford came to the conclusion that an atom's nucleus must have a positive charge as a result of this.
To learn more about the atomic models here, refer to the link;
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Worldwide, the total number of land animals killed for food every hour is ______.
1. 8 thousand animals
2. 500 thousand animals
3. 1 million animals
4. 8 million animals
Answer:
8 million animals
Explanation:
This is because all over the world, animals are consumed as food and they serve as source of protein.
Animals are used to make different delicacies depending on the choice of the consumer and it is the major source of protein. Every hour, about 8 millions are killed and are sold to consumers and other parts of it can be use for other things. Examples of animals consumed are goat, sheep, cow, chicken e t.c.
A circular loop ( radius = 0.5 m) carries a current of 3.0 A and has unit normal vector of (2i - j +2k)/3 what is x component of the torque on this loop when it is placed in a uniform magnetic field of (2i-6j) T
Answer:
[tex]T=9.42Nm[/tex]
Explanation:
From the question we are told that:
Radius [tex]r= 0.5 m[/tex]
Current [tex]I= 3.0 A[/tex]
Normal vector [tex]n=\frac{(2i - j +2k)}{3}[/tex]
Magnetic field [tex]B= (2i-6j) T[/tex]
Generally the equation for Area is mathematically given by
[tex]A=\pi r^2[/tex]
[tex]A=3.1415 *0.5^2[/tex]
[tex]A=0.7853 m^2[/tex]
Generally the equation for Torque is mathematically given by
[tex]T=A(i'*B)[/tex]
Where
[tex]i'*B= \begin{bmatrix}2&-1&2\\2&-6&0\end{bmatrix}[/tex]
[tex]X\ component\ of\ i'*B= [(-1 * 0)-(2*-6)][/tex]
[tex]X\ component\ of\ i'*B=12[/tex]
Therefore
[tex]T=0.7853*12[/tex]
[tex]T=9.42Nm[/tex]
What voltage (potential difference)must be applied to a 26 1
resistor to cause a current of 0.50 A to flow through it?
0 6.5 V
0 13 V
26 V
0 52 V
Answer:
26v
....................
_______ is in continuous motion in _____, spinning as it moves around the _______. Fill in the blank..
Answer: Earth is in a continuous motion in space, spinning as it moves around the sun.
(Hope this helped!)
Answer:
motion in space and moves around the sun
Explanation:
I hope this helps
I have an idea but I just want to be sure
plsssss asappppppppp
Answer:
20 meters.
Explanation:
In the graph, the x-axis (the horizontal axis) represents the time, while the y-axis (the vertical axis) represents the distance.
If we want to find the distance covered in the first T seconds, you need to find the value T in the horizontal axis.
Once you find it, we draw a vertical line, in the point where this vertical line touches the graph, we now draw a horizontal line. This horizontal line will intersect the y-axis in a given value. That value is the total distance travelled by the time T.
In this case, we want to find the total distance that David ran in the first 4 seconds.
Then we need to find the value 4 seconds in the horizontal axis. Now we perform the above steps, and we will find that the correspondent y-value is 20.
This means that in the first 4 seconds, David ran a distance of 20 meters.
Can someone please help meee!! >.<
One day, you went for a walk with your family on the beach. You noticed that there was a lot of trash and a large oil spill in the water. Please write in a long term paragraph.
A bicycle with a mass of 100kg hit a wall at an acceleration of 4 m/s2, what is the force?
Answer:
400N
Explanation:
F= ma
F= 100 x 4
F= 400N
Microwaves travel at the speed of light, 3x108m/s. When frequency of the microwaves is 9x109 Hz, quantitatively translate this information into their wavelength and period. Wavelength= 0.03m; period 1.1x10-10s , , Wavelength= 0.03m; period 1.1x10 -10 s, Wavelength= 0.03m; period 1.1x10-10s Wavelength= 0.03m; period 1.1x10 -10 s, Wavelength = 0.03cm; period 1.1x109s Wavelength = 0.03cm; period 1.1x10 9 s, Wavelength=0.03m; period 1.1x1010s
Explanation:
Given that,
The frequency of microwaves, [tex]f=9\times 10^9\ Hz[/tex]
The time period of the wave is :
[tex]t=\dfrac{1}{f}\\\\t=\dfrac{1}{9\times 10^9}\\\\t=1.1\times 10^{-10}\ s[/tex]
Let [tex]\lambda[/tex] is the wavelength of the wave. We know that,
[tex]v=f\lambda\\\\\lambda=\dfrac{v}{f}[/tex]
Put all the values,
[tex]\lambda=\dfrac{3\times 10^8}{9\times 10^{9}}\\\\\lambda=0.03\ m[/tex]
Hence, this is the required solution.
Which statement should she place in the region marked X?
A. Electrons move between objects.
B. The objects do not touch.
C. The objects develop opposite charges.
D. The objects have the same charge.
Electrons moving between objects should be place in the region marked X. So, option A.
What is meant by charge ?When a substance is exposed to an electric or magnetic field, it has a characteristic known as charge that makes it experience a force. Neither a positive nor a negative charge exists.
Here,
Normally, electrons are organized into specific shells that maintain a constant distance from the atom's nucleus.
Two electrons can fit inside of the shell that is closest to the nucleus. Up to eight can fit inside the following shell. The number of electron shells in some atoms with numerous protons can reach seven.
A powerful force of attraction exists between the protons and the electrons in the shells that are closest to the nucleus.
In the outermost shells of certain atoms, the protons are sometimes attracted to the electrons with little force.
One can force these electrons out of their orbits. They may switch from one atom to another by applying a force. Electricity is produced by the changing electrons.
Hence,
Electrons moving between objects should be place in the region marked X. So, option A.
To learn more about charge, click:
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On which planet can you jump about the same height as Earth? Explain your answer.
Answer:
Venus
Explanation:
Venus and earth have a similar gravitational pull because they are almost the same size (venus is slightly smaller) and because of the similar mass.
the light beam falls on the surface of the mirror at an angle of 50 ° and is reflected. What is the magnitude of the reflection angle of that fiber?
Answer:
The Magnitude of the angle of reflection equals that of Incidence from the Law of reflection
So its 50°.
Explanation:
Photo below with question, please help need to confirm answer
Is the answer A?
Answer:
Only circuit A will contain to lit bulbs
If an external force and the frictional force are acting on a body, which is in rest on the floor and are equal and opposite, then the frictional force is _____
If an external force and the frictional force are acting on a body, which is in rest on the floor and are equal and opposite, then the frictional force is Static friction.
Can someone write a 200 speech that explains the difference between analog and digital waves and which one is better?
Answer:
Analog and digital signals are the types of signals carrying information. The major difference between both signals is that the analog signals have continuous electrical signals, while digital signals have non-continuous electrical signals.
Explanation:
Analog Signals were used in many systems to produce signals to carry information. These signals are continuous in both values and time. The use of analog signals has been declined with the arrival of digital signals. In short, to understand the analog signals – all signals that are natural or come naturally are analog signals. Digital Signals , unlike analog signals, digital signals are not continuous, but signals are discrete in value and time. These signals are represented by binary numbers and consist of different voltage values. Their differences are as follows:
Analog Signals Digital Signals
Continuous signals Discrete signals
Represented by sine waves Represented by square waves
The Human voice, natural sound, analog electronic devices are few examples Computers, optical drives, and other electronic devices
A Continuous range of values Discontinuous values
Records sound waves as they are Converts into a binary waveform.
Only be used in analog devices. Suited for digital electronics like computers, mobiles, and more.
I think a Digital signal is better.
Imagine that a 1200 kg vehicle speeds up from rest to 20.0 m/s in 80 m.
How much work was done on the car? (Answer in 3 sig figs)
Correct question:
Imagine that a 1200 kg vehicle speeds up from rest to 20.0 m/s in 80 s.
How much work was done on the car? (Answer in 3 sig figs)
Answer:
the work done on the vehicle is 2.40 x 10⁵ J
Explanation:
Given;
mass of the vehicle, m = 1200 kg
initial velocity of the vehicle, u = 0
final velocity of the vehicle, v = 20 m/s
time of motion of the vehicle, t = 80 s
The distance moved by the vehicle is calculated as;
[tex]s = (\frac{v + u}{2} )t\\\\s = (\frac{20+ 0}{2} )(80)\\\\s = 800 \ m[/tex]
The force applied to the vehicle is calculated as;
[tex]F = ma = \frac{m v}{t} = \frac{1200 \times 20}{80} = 300 \ N\\\\[/tex]
The work done on the vehicle is calculated as;
W = F x d
W = 300 x 800
W = 2.4 x 10⁵ J.
Therefore, the work done on the vehicle is 2.40 x 10⁵ J
help again please !!!
What is the name of the process taking place in the diagram? Describe the process
1st question
name of impurities present in zinc plate used in simple cell.
Mercury is present in zinc plate which is used in simple cell
Linus builds an electrical circuit with a battery and with wires that carry the current. As the battery weakens, the current also weakens. How does this affect the magnetic field around the wires
Answer:
When electric current weakens then the magnetic field around the wire also weaken
Explanation:
The magnetic field produced by electrical wire is directly proportional to the electricity flowing through it.
Thus, in case when electric current weakens then the magnetic field around the wire also weaken.
Answer:
The field gets weaker
Explanation:
took the quiz!
Two charges create 8.00 N of electric
force on each other. If you increase
their distance to twice its original
value, how much electric force do
they exert on each other?
(Hint: How does Fe change with distance?)
[?]N
Answer:
2.00 (right on acellus)
Explanation:
doubling the distance between two charges makes F (8.00) quarter, so you would just do 8.00*1/4.
A ferry boat is 2.0 m wide and 4.0 m long. When a truck pulls onto it, the boat sinks 2.00 cm in the water. What is the weight of the truck?DENSITY OF WATER IS 1000 Kg/m^3
Answer:
156,800 N
Explanation:
Given: Width = 2.0 m Length = 4.0 m Depth = 2.00 cm. Density of water = 1000 Kg/m³
To find: What is the weight of the truck?
Formula: [tex]F = m[/tex] × [tex]9.8 m/s^2[/tex]
Solution: Weight is a measure of the force of gravity pulling down on an object. It depends on the object's mass and the acceleration due to gravity, which is 9.8 m/s² on Earth. F is the object's weight in Newtons (N) and m is the object's mass in kilograms.
Firstly, multiply the length, width, and depth.
[tex]2.0[/tex] × [tex]4.0[/tex] × [tex]2.00[/tex] [tex]= 16[/tex]
Next, the weight of the truck is found by multiplying the density of water, the result found by multiplying the length, width, and depth, and the formula;
[tex]1000 kg/m^3[/tex] × [tex]16[/tex] × [tex]9.8m/s^2[/tex][tex]= 156,800[/tex]
Therefore, the weight of the truck is 156,800 N
lana summarized what happens when a ball sitting on top of a grassy hill rolls down the hill.
The motionless ball has potential energy. Once the ball starts to roll down the hill, new kinetic energy is made. As the ball rolls across the grass, it slows down. The kinetic energy of the ball is converted to other forms of energy.
Which best describes Alana’s error?
The motionless ball does not have energy because it is still.
Kinetic energy is not made; it is a result of energy transformation.
The ball cannot slow down unless someone touches it.
The energy is not converted; it disappears.
Answer:
Kinetic energy is not made; it is a result of energy transformation
Explanation:
Let's discuss what happens to the ball when it is on top of the mountain and rolls down.
Initially the ball has a total mechanical energy, which at this point is potential.
Em₀ = U = mg h
When the ball starts to roll down, part of this potential energy will be transformed into kinetic energy.
Em = K + U = ½ m v² + mg y
but mechanical energy is conserved.
The presence of the grass introduces a force in the opposite direction that creates a friction force work (not conservative), for which the total mechanical energy decreases
W_{friction}= Emf - Emo
When examining the answers, the one that best describes Lana's error is:
Kinetic energy is not made; it is a result of energy transformation
Answer:
Your answer is B) Kinetic energy is not made; it is a result of energy transformation.
Explanation:
the electric cell of internal resistance 0.5ohms delivers a current of 2 amperes when a resistance of 3 ohm is connected across it, find the electromotive force of the cell. Show all workings
Answer:
7 volts
Explanation:
Applying,
E = IR+Ir................ Equation 1
Where E = electromotive force of the cell, I = current. R = External resistance, r = internal resistance.
From the question,
Given: I = 2 amperes, R = 3 ohm, r = 0.5 ohm
Substitute these values into equation 1
E = (2×3)+(2×0.5)
E = 6+1
E = 7 volts
Help please thank you
Answer:
A. 1 unit
B. 5 units
C. 8 units
Explanation:
Count the lines from each starting point to each destination.